Water Tank Installation Guides

Water Tank Installation Specifications


Promax Water Tanks must be installed according to these instructions.

  • Failure to follow these installation instructions will void the warranty and may result in tank failure.
  • Proper installation of tanks is required to prevent tank damage and ensure long term trouble free service.
  • It is imperative to read and understand the instructions below prior to any installation commences.
  • Promax will not be held liable for any cost associated with poor installation.
  • Promax Enduro and Xpress Tanks are only to be used for storing water at ambient temperatures.

1. Delivery

Our Big Tanks (10000L – 30000L) are delivered free delivery to your property. All other products will be delivered via Mainfreight unless otherwise specified.

Transportation to the actual site and installation is the risk and responsibility of the purchaser. Where there is suitable road access, our drivers may agree to off-load closer to the installation site, however please note that this will be at the purchaser’s risk and drivers discretion. All aboveground tanks 10000L – 30000L are delivered nationwide on our fleet of purpose-built trucks. The clearance required for our truck and trailer is 21 metres long, 5 metres high and 3.5 metres wide. The truck only (without the trailer) is 11 metres long, 5 metres high and 3.5 metres wide. If you require a hiab delivery, please advise us prior to arrival in order to ensure we have a hiab truck available – an additional hiab charge will apply.

You must advise Promax Plastics immediately of transport damage prior to sitting and installing your tank.

2. Handling

Promax recommends the following for normal situations where a tank is required to be lifted into position using the moulded in lifting lugs.

  • All 4 x lifting lugs must be used.
  • Tank must be empty of all contents – DO NOT attempt to lift a tank containing water.
  • Long chains or strops to be used to lift the tank and all the same length.

These recommendations are for ground based lifting and do not include aerial transport. Promax recommends the use of compliant lifting equipment to Work Safe New Zealand guidelines.

3. Tank Base Preparation #1

Sand

Ensure the tank site is level and free from any foreign matter or projections such as rocks, roots or stones that may damage the
tank base.

  • Ensure the tank site is well compacted if fill is used to prepare or level the site.
  • Ensure that the tank site is at least 300mm larger in diameter than the tank.
  • Use level 100mm layer of sand, fine gravel (<7mm) or crusher dust as a base to sit the tank on.
  • If a sand base is used, a retaining cover must be provided to prevent sand from washing away after installation.
4. Tank Base Preparation #2

Partially buried

Promax Enduro tanks 10000 – 30000L may be buried to 1m in ground if the following instructions are adhered to.
Promax Enduro tanks 450L – 5000L may be buried in the ground to 1/3 of their side wall height if the following instructions are adhered to.

  • Ensure the tank site is level and free from any foreign matter or projections such as rocks, roots or stones that may damage
    the tank base.
  • Ensure the tank site is well compacted if fill is used to prepare or level the site.
  • Ensure that the tank site is at least 300mm larger in diameter than the tank.
  • Use level 100mm layer of sand, fine gravel (<7mm) or crusher dust as a base to sit the tank on.
  • Tank must be filled with water to the ground level before backfilling.
  • Backfill evenly around the tank with sand, clean dirt or bark. Allow to settle naturally without undue compaction.
5. Tank Base Preparation #3

Concrete

  • Tanks may be placed on a smooth concrete base pad providing this is constructed such that it will support the tank weight
    (full of water) without the possibility of cracking or shearing.
  • Promax recommends a minimum 100mm mesh reinforced concrete 20MPA.
6. Plumbing Your Tank

It is the responsibility of the purchaser to ensure the tank is installed correctly using the guidelines supplied by Promax Plastics and best plumbing practice. If supplied, bungs are screwed in for transport only. If used permanently, remove and apply thread tape or sealant before screwing back in. This must be completed before filling the tank.

Because polyethylene water tanks expand when full, plumbing to the tank must be flexible. Polyethylene pipe does not constitute flexible plumbing. Flexi-hose needs to be used to provide sufficient flexibility.

Failure to install an overflow on your tank will void the warranty. Minimum recommended overflow size equal to the number and size of inlet pipes OR 90mm, whichever is greater, to avoid the build-up of internal pressure or vacuum. Air and water must be able to exit the tank at the combined maximum rate that it can enter. If the tank is not sufficiently vented it may suck in the dome of the tank.

  • Downpipe Inlet/s can be installed through the ports moulded in the tank roof, or anywhere directly through a flat surface on the roof of the tank providing there is
    room for a pipe seal to seat and seal properly.
  • Ballcock fed inlets are recommended to be installed within reach of the manway. A ballcock inlet does not negate the need for an overflow.
  • PVC downpipes should be installed through a rubber pipe seal, seated, and sealed properly.
  • PVC Downpipes can be installed through the side wall of the tank in the top 500mm of the tank wall through a rubber pipe seal.
    A Wallace Seal will seal through the corrugations.
  • Overflow pipe/s must match the incoming pipe/s flow capacity.
  • Pipe overflow away from the base of tank to prevent erosion.
  • Use the appropriately sized hole saw to cut the hole for inlets and outlets.
  • Pipework between tanks or rigid structures must include a flexible hose to allow for expansion & contraction.
  • Do not fit any additional outlets closer than 300mm to any other outlet.
  • The maximum flanged tank fitting size is 100mm.
  • All fittings must be supported independently such that the fitting is causing no stress to the tank wall and base.
  • Heavy unsupported loads are not permitted on the tank dome or wall – this includes standing on the dome under any circumstances or unsupported pipework.
7. Cleaning and Maintenance

Your tank should be cleaned on a regular basis. We recommend you use a professional tank cleaning company to do this. A professional tank cleaning company is able to vacuum the base of your tank without emptying the water. Alternatively, you could
consider installing a Tank Vac. These will remove build-up of sediment already present and help keep your tank clean all the time. Promax recommends that you clean your tank out at least annually, however it is important to inspect your water tank on a
quarterly basis

8. Warranty Policy

Promax guarantees the original purchaser that it’s tanks will be free from material defects during the manufacturing process and will at its discretion replace or repair on a pro-rata basis for a period limited to:

  • 20 years from date of purchase for premium PROMAX ENDURO Tanks 10,000L and above.
  • 20 years from date of purchase for XPRESS Tanks 10,000L and above.
  • 5 years from date of purchase for all XPRESS and PROMAX Tanks 5,000L and below.
  • 5 years from date of purchase on Underground Tanks
  • 10 years from date of purchase on Underground Tanks ENDURO series
  • 2 years from date of purchase for Diesel Tanks
  • 1 year on all other items

Your product must be registered on our website www.promaxplastics.co.nz within 30 days from delivery date. An original invoice must be provided when submitting a warranty claim. Promax warranties are not transferable.

ABOVE GROUND WATER TANK
INSTALLATION INSTRUCTIONS

It is important You Read and Understand this Information
Before Installing Your Tank

1. Location:
Locating your tank in a shady area may help keep the water cool and your tank cooler. In deciding where to best place your tank be mindful of proximity to buildings and other structures. Owners are advised not to enclose tanks following installation, or install such that sufficient expansion of the tank will be restricted (i.e. do not place tanks hard up against fixed walls, fences, or structures. Doing so will void your warranty).

All tanks placed in open areas where livestock have access must be fenced to a minimum of 1.0 metre from the tank to avoid any possible damage to the tank wall. In areas prone to strong or gusty winds (e.g. hilltop locations) stabilising wires must be located through the lifting eyes in the top roof ribs and secured to the ground, particularly where the water level in the tank may vary considerably. Failure to meet these requirements will void the warranty.
In areas prone to rabbit or other burrowing animals wire mesh will be required to be erected in a narrow trench around the foundation perimeter to a minimum depth of 600mm. Failure to do so will void the warranty.

2. Site Preparation:
Firm flat level ground foundations are required. Ensure the platform for the tank is on solid (compacted) stable free draining ground. The level site must extend a minimum of 300mm greater than the diameter of the tank and must be cleared of any sharp projections such as rocks, stones, or roots. Because ribbed tank walls allow for the weight to be distributed over the largest possible area (31,000 litres = 31 metric tonnes) the tank must sit on a level flat site. If you are placing a smaller tank on an elevated structure (i.e. deck or tower) an engineers report must be made available to the tank manufacturer for approval prior to installation. Always check with your local council to ensure you meet current requirements.

A uniform 100mm minimum depth compacted sand or Gap 7 bedding must be contained such that it cannot be washed or eroded away. A timber or concrete retaining nib wall is required to retain the bedding. Failure to do so will void the warranty.

Where the tank is being placed on sloping ground a flat level area at least 600mm greater than the tank diameter must be excavated and a retained sand bed as described above constructed. The high side of the bank must be retained to hold soil from collapsing against the tank. Drain coil or similar drainage material must be used around the wall face and drain away from the tank site to ensure the tank base material is not eroded. Failure to do so will void the warranty.

Tanks exceeding 10000lts may be buried up to a maximum of 700mm(2nd rib) providing all other criteria relating to the installation and site preparation have been met.

Placing the tank on a level concrete pad is acceptable, however the pad must be suitably constructed such that it will support the tank weight (full of water, (1000ltrs = 1000kgs) without the possibility of cracking or sheering and ultimately presenting an uneven surface to the bottom of the tank which could ultimately result in its failure. This occurrence will not be covered by warranty.

3. Tank Installation:
Once the tank has been carefully placed in position without disturbing the compacted sand base ensure that there are no visible gaps between the bedding sand and bottom of the tank – if so fill the gaps.

IMPORTANT:

When using lifting equipment ensure all tank lifting points are used with an angle of less than 90 degrees at the apex of lifting ropes or chains. Always lift the tank empty and adhere to Occupational Safety and Health regulations. Failure to do so will cause damage and void the warranty. (Refer drawing on next page)

All tanks whether gravity-fed or pressure-fed through a ball valve, float, or other such system must be fitted with an overflow pipe, or pipes to equate to a size greater than 25mm diameter more than the inlet pipe(s) – a minimum of one overflow must be fitted for each inlet pipe. In all installations the overflow pipe(s) must be at a point lower than the inlet pipe(s) to allow the overflow to operate prior to the tank overfilling. Failure to meet these requirements will void the warranty.

All inlets and outlets must be cut out with a hole-saw in the designated areas (i.e. in either of the two manhole riser structures. All external pipework must be fully supported. Do not allow the weight of suspended pipework to rest on the wall or roof of the tank without being adequately supported. Do not allow the weight of any pipework to bear on the pre-threaded outlet without being adequately supported (refer instructions on outlet flexible hose). Failure to meet these requirements will void the warranty.

All overflow pipes must be plumbed to run water at least 300mm away from the contained base material area to where sand and soil are not likely to be eroded or undermined. Failure to do so will void the warranty.

Note: The mesh air vent fitted to the riser on AQ16000, AQ21000, AQ25200 and AQ31000 is NOT an overflow.
Do not cut any holes or mount any fixture in the tank walls or domed roof other than the designated reinforced areas described above, without prior written approval from the manufacturer. All holes for inlets and overflows must be cut using correct tools (hole-saw). Failure to do so will void the warranty.

4. Connecting the Tank Outlet:
BSPT (tapered) fittings must be used when connecting to the outlet. It is recommended that a thread sealing tape be used on all threads to avoid leaks and subsequent foundation erosion. Care must be taken when tightening all fittings – do not over tighten (over tightening of tapered thread fittings may result in stripped threads or undue expanded stress on the fittings and/or the tank material). Always secure the pre-threaded tank outlet fitting with a spanner when tightening other fittings into this aperture.

A section of flexible hose must be used between the tank outlet fitting and main feed line away from the tank. Ensure all above ground pipe work is supported level with outlet fitting as shown (refer diagrams below). If buried Alkathene pipe is to be used then a section of flexible pipe must be fitted immediately from the tank outlet before the main line is buried. Any pressure, loading, twisting or bending on the outlet pipe work or tank fitting area must be avoided and may result in tank failure. This occurrence will not be covered by warranty.

5. Safety:
Tanks, including domed roof areas are not designed to be walked on other than to enter the man hole entrance, regularly checking inlets, overflows, and breathers are clear of debris or to fit a water vane. Do not enter the tank if working alone. Do not allow children to climb or play on tanks. . For safety reasons it is recommended that the lid is secured with the screw that is supplied to stop unauthorized entry to your tank

6. Ongoing Maintenance:
Should the foundation settle slightly when the tank is initially filled with water, and in many cases it will, polyethylene is sufficiently elastic to conform to the ground shape without damage to the tank. However erosion of the bedding sand from around the wall edges must be replaced and the cause of such erosion eliminated. This could cause failure of the tank and void the warranty.

Ensure overflow pipes and breather pipes never become restricted or blocked as excessive pressure build up in the tank could cause failure of the tank. (If you are situated in an area with excessive or extreme rainfall patterns additional overflow pipes and breathers are recommended to help relieve your tank in these instances. Failure to meet these requirements will void the warranty.

As part of your regular on-going maintenance program, check for any obvious signs of damage to the tank, foundation, and pipe work and attend to any repairs that may be necessary as quickly as possible. The majority of water tank failures are as a direct result of poor or incorrect installation and/or lack of regular maintenance. It is your responsibility to look after the product and to hold any warranty and purchase information in a safe place. In the event of a problem you will be asked to provide specific information and photographic evidence as part of a claim process. Failure to supply this information may compromise any claim.

7. Tank Use:
Your Aqua tank is designed for everyday use but in situations where your tank fills and empties on a regular basis such as irrigation or continual cycling it is recommended that an additional breather kit be fitted as failure to do so may void your warranty. An additional Breather Kit is available from your Aqua Tank agent or directly from the manufacturer (0800 370 007). This is also recommended for tanks that have larger than standard outlets ie greater than 50mm (2”)

 

Devan Water Tanks. Made in New Zealand for New Zealand Conditions!

In order to gain maximum benefit from your Devan water tank, we have outlined the following instructions for installation and setup. Please read all these instructions carefully before installing your tank. The tank warranty will be void if the installation instructions are not adhered to.

DELIVERY OF YOUR DEVAN TANK

Devan water tanks are delivered by road to your gate. Transportation to the actual site and installation is the risk and responsibility of the purchaser. Where there is easy and suitable road access, our drivers may agree to off-load closer to the installation site, however this will be at the purchaser’s risk. On arrival please make sure that somebody is available to help our drivers off-load your tank.
Our drivers will phone the person nominated at the time of order on the morning of delivery to confirm details. They will advise an approximate delivery time. If the driver is unable to get hold of the nominated contact person, the tank will be off-loaded at the most convenient location at the site and it will be the purchasers responsibility to relocate the tank at their risk and responsibility.
If you have special access issues, please make sure these are made known either to the Devan sales team or to the driver. Examples of such issues include truck only access in tight spaces, farm gate entry as opposed to main driveway or tanker track entry or no wet weather access.

FOUNDATION AND LOCATION

A full Devan tank is extremely heavy (up to 30 tonnes). Be thoughtful in selecting your tank location.

When installing the Devan tank, choose a firm and level area that is free from any projections. Elevated locations must have a solid floor and be strong enough to withstand wind loads in conjunction with the weight of a full tank.

A level foundation is required for tanks 5,000 litres and larger. Concrete, quarry fines (<7mm), pumice and sand are all suitable.

Sand is the recommended option. The sand base needs to be 100mm deep, 500mm greater than the tank diameter and most importantly, free from any sharp objects or projections such as rocks, roots or stones.

The sand base must be retained at all times. Pipe tank overflow well clear of the sand base to ensure overflowing water does not aid erosion.

In high wind areas such as hilltops, the Devan tank can be secured to the ground using all four lifting lugs. Do not overtighten the tie-downs or damage will result. Devan water tanks are not designed for in-ground installation but can be buried up to 500mm and back filled with clean fill. If further depth is required tanks must not be buried any further than a maximum of 1000mm below ground level keeping a free space of at least 500mm around the tank. This space should have drainage installed and the gap filled with bark so it is not a trap hazard for small animals or children.

Devan tanks can be recessed into banks or similar, providing the tank is not backfilled against and there is free space of at least 500mm around the tank.

Do not install water tanks over buried pipes, cables or any other utility connections which may require servicing or maintenance.

Do not install water tanks over underground structures such as cellars, septic tanks, sewage canals, etc.

Do not install water tanks where they could pose a potential hazard to life or property. eg under foundations or within a building.

In areas prone to rabbit or other burrowing animals it is advisable to bury wire mesh to a depth of at least 600mm in a narrow trench around the foundation parameter.

In areas where livestock have access to the tank, the area surrounding the tank should be fenced to a minimum of 1.0 metre from the tank, to avoid any damage to the tank wall or outlet fittings.

Where the tank needs to be lifted into place, all four lifting eyes must be used in doing so. The lifting eyes are not rated sufficiently to be used with any water in the tank.

BOTTOM OUTLET PLUMBING GUIDELINES

Bungs are screwed in loosely for transport only. If used permanently, please remove the bung and Teflon tape the threads and screw back in. Do not overtighten the bungs if they are to be refitted. This procedure must be completed before filling the tank.

Because polyethylene water tanks expand when full, plumbing to the tank must be flexible. Tanks will expand 30 to 40mm from new when filled for the first time. Tanks will contiune to expand up to 100mm over their life span.

All plumbing attached to the bottom of the tank must be done correctly with all base connections flexible and free from stress. Plumbing kits are recommended and are available from Devan in 25mm, 32mm and 50mm sizes.

Polyethylene pipe does not constitute flexible plumbing. Flexi-hose needs to be used to provide sufficient flexibility.

No extra penetrations are to be cut into the walls of the tank without written approval of the manufacturer. Doing so will seriously affect the structural integrity of the tank and could lead to premature failure.

There are specially designed mounting areas on the wall of the tank for outlet plumbing with brass fittings moulded-in for extra plumbing strength. These fittings are pre-drilled and tapped ready for use. These moulded-in fittings are raised off the bottom of the tank to prevent sludge pick-up and to retain sufficient weight (up to approx. one tonne in large tanks) making the tank more stable in exposed areas.

It is not recommended to install tank fittings anywhere else in the tank wall as this will create a stressed point in the tank structure and void the warranty. If an outlet fitting is required at a specific level, connect an internal vertical pipe to the desired level from the inside of the provided wall mounted outlet. These Restricted height outlets are available for purchase from Devan.

All pipe fittings larger than 25mm must be supported independently to minimize stress on base. Please use only appropriate PVC or polyethylene fittings and make sure that all joints are flexible and are well sealed and watertight with no light penetration.

Where a bottom outlet fitting of over 50mm is required it is strongly recommended that the tank be upgraded to heavy duty or extra heavy duty to accommodate the high-use nature of the application. If a larger fitting is installed in a standard tank it will void the warranty.

Any aftermarket fittings installed in the tank wall or base will void warranty.

TOP PLUMBING

Connecting to the dome

There are specially designed mounting areas on the dome of the tank, for inlet and overflow plumbing. We recommend the use of Universal seals® with all top plumbing and care should be taken when drilling the corresponding hole size. Proper hole saws must be used.

Universal seals® are available from Devan (25mm to 100mm).
The overflow should be piped away from the foundation to avoid erosion.

Overflows

An overflow must be installed in all instances to let excess water out of the tank. This is also important if the tank is filled from a float valve in case it sticks open.

A ‘Hockey stick’ shaped overflow will not provide sufficient out flow in instances of heavy rain and failure to allow could lead to the tank dome eventually vacuuming in.

Ninety degree overflow and vent pipe work is essential.

Venting

It is essential that you have more than adequate overflow and air venting for your operating conditions. Air and water must be able to exit the tank at the combined maximum rate that it can enter. If the tank is not sufficiently vented it will inevitably suck in the dome of the tank which will cause the tank to fail prematurely.

For high flow situations such as a wash down tank at a cowshed an appropriate size vent must be installed in the dome. Venting options are available from Devan.

WATER PUMP INSTALLATION

Do not directly install water pumps to the side of your water tank. The water pump and its motor must be self-supported on its own mount and connected to the tank via flexible hose to isolate any vibration or movement by the pumping unit itself. The tank outlet areas and their fittings must not be stressed by the weight of the water pump, motor or plumbing.

Remember to allow more than adequate overflow and venting when water pumps are used. Air and water must be able to enter or escape the tank at the same rate the water is being pumped in or out. Use the top plumbing areas when attaching overflow or vent plumbing to your water tank.

WARRANTY POLICY

Your Devan product has been manufactured to the highest standards utilising advanced technology and production procedures. Devan Plastics Limited (“Devan”) offers a warranty to the original purchaser that their products to be free of defects in workmanship or materials for the period defined in Appendix A, provided the provisions detailed below have been complied with.

A third party manufacturers’ warranty applies to all other components used in the manufacture of Devan products. Third party manufacturer’s warrant their products are free from defects in material and workmanship at the time of shipment and will make good, by repair or at its option replacement, any defects which occur during the warrantable period as defined in Appendix A provided the provisions below have been complied with.

Necessary provisions

In order for a warranty claim to be accepted by Devan or a third party manufacturer the following provisions must be met:

  1. The equipment was correctly installed and in proper use as was intended by the manufacturer in accordance with the Installation and operating instructions supplied, and generally accepted code of practice or national standard/s.
  2. The warranty period (as defined in Appendix A) from the date of invoice to the end user has not lapsed.
  3. The claim for goods under warranty arises solely from faulty material or manufacturers’ workmanship.
  4. The customer or agent of the customer must return goods under warranty (where appropriate), stating the date and place of purchase promptly and within the product warranty period.
  5. No repairs must be entered into by anybody other than a specified distributor or repairer as agreed and appointed by Devan.
  6. Devan must be given a reasonable opportunity to inspect the tank and, if deemed necessary by Devan to have an independent engineering or other expert analysis of the cause of failure carried out.

Exclusions

Both the Devan warranty and third party manufacturer’s warranty do not cover the following exclusions:

  1. Except where otherwise stated by law, the manufacturer shall not be under liability for any injury, damage, or loss, including consequential damage or loss resulting from the use of its products, or resulting from defects therein. This may specifically refer to the cost of but not limited to lifting, installation, electrical or plumbing requirements.
  2. Damage caused by abnormal operating conditions, war, violence, cataclysm, or any force majeure.
  3. Damage caused by the equipment being used for an application for which it is not manufactured or recommended by the original manufacturer or Devan.
  4. Damage caused by sand or abrasive materials, corrosion due to salt water, hazardous liquids, electrolytic action, and liquid temperatures beyond the recommended range, cavitation, and improper power supply voltage or outages.
  5. Attempted repair, dismantling or any other tampering with any component of the system without the prior written approval of Devan will void any warranty.
  6. If the Devan product or third party component has not been maintained in accordance with Devan.
  7. Ingress of water or insect infestation to electrical components due to post-manufacture electrical penetrations not being appropriately protected.
  8. Incorrect installation or negligent practices of the installer of the product.
  9. Tank colour that may change or fade over time.
  10. Any transport, insurance and freight costs.

This warranty does not exclude any condition or warranty implied by the Consumer Guarantees Act 1993, Fair Trading Act 1986, and the Commerce Act 1986 and is in addition to any rights the purchaser may have at law.

Appendix A – Product warranty periods

CLEANING AND MAINTENANCE

Depending on the cleanliness of your water source, your water tank should be cleaned on a regular basis.

What can end up in my water?

Algae growth is a common occurrence in water tanks. Devan water tanks are manufactured to strict quality tolerances, meaning that no light can penetrate the tank which will eliminate any algae growth, as algae need light to exist. Sometimes the nature of an installation can change this whereby an installer may cut oversized holes for inlets or overflows/venting. Blocking up any points for light to enter the tank will reduce or eliminate algae growth in the tank.

External debris are a much more visible source of contamination that will either float on the top of the water, of form sediment on the bottom of the tank. Such contaminants will consist of leaf litter, bird droppings, dead insects and even animals. This debris will build up on the bottom of your tank and require removal periodically.

Cleaning frequency

Devan recommend that you clean your tank out at least annually; however it is important to inspect your water tank on a quarterly basis to assess the level of contamination. A quality installation with the right pretreatment accessories could mean your tank remains in immaculate condition for a number of years before requiring cleaning. Cleaning of your tank will either take a bunch of your time or money and so the less frequently you need to clean it, the better. If you are noticing the rapid build up of sediment on the bottom of your tank, investigate the options for pre-treatment.

Devan tanks have outlet locations positioned up off the bottom of the tank which means you are not drawing off the contaminated water at the bottom of the tank for your day to day consumption. This is a precautionary measure only and should not be relied upon to prevent organic material entering your water supply.

Tank cleaning options

Although a self clean (described below) is a relatively straight forward exercise, it can be very time consuming, while a contractor will have it done in a couple of hours.

Do it yourself

Warning: If you will be getting into the tank to clean it, make sure there is adequate ventilation, and you have another person present at all times in case something should go wrong. Working in confined spaces is dangerous and should not be attempted by an individual working alone.
Draining the tank down to the last 1-2 thousand litres through the spare outlet will concentrate all contaminants into the bottom of the tank. The quickest and easiest way to then remove the concentrated contaminants is to hire a wet vacuum system or pump and stir up all the debris with a soft broom, which will then be sucked out by the vacuum or pump.

Siphoning off sediments may also be done using an inverted funnel (described below) or pool vacuum cleaner, by dragging it along the bottom of the tank.

INSTALLATION INSTRUCTIONS

IMPORTANT!

Incorrect installation will void your warranty

  • Bailey Water Tanks are to be used only for storing water at ambient temperature.
  • Delivery is to the road entrance of your property (providing access is suitable).
  • Transportation to the site is at the driver’s discretion.
  • Installation is the responsibility of the purchaser.
Site Preparation

The site should be firm, level, stable ground. It should be at least 600mm greater in diameter than the tank. The base should be adequately and uniformly supported over its whole area. Do not place the tank on beams with interval spaces. Ensure that the
area is free from any sharp objects such as stones or roots. A concrete pad or 100mm deep compacted sand is recommended and should also be 600mm greater in diameter than the tank. If using sand it should be boxed in with 4×2 timber to avoid erosion. If locating the tank on a sloping section make sure that the area will not erode and do not backfill against the tank.

  • The tank is not to be buried.
  • Do not walk or put weight on the dome of the tank this is unsafe and could also damage the tank.
Plumbing

A 2” BSP outlet is fitted to the base of the tank ready for you to screw in your fittings, a reducing bush / nipple can be fitted if required.
No extra penetrations are to be cut into the sidewalls of the tank without written consent from the manufacturer. No penetrations are to be cut into the base.
A specially moulded box with flat sides is conveniently located to the front of the inspection hatch at the top of the tank. All fittings: inlet, overflow, ballcock, water level indicator etc should be installed here. Therefore it is not necessary to walk on the dome.
Connection between the tank and pump should include a flexible hose (not polyethylene pipe) to absorb vibration.
If connecting multiple tanks together or connecting a tank to a rigid structure, flexible hose should be used or a 90-degree loop to allow for expansion or shrinkages.
Pipe the overflow away from the foundation to prevent erosion.
The cap in the middle of the dome is used during manufacture and should not be used for installation. Do not remove this cap.
The lid is vented and offset for ease of inspection.

PLEASE NOTE a 5,500 gallon tank weighs 25 tonne when it is full so take care with preparation of the site and the installation of the tank.

Authorised Bailey Tank agents may in certain circumstances deviate from these instructions providing they stay within the manufacturers guidelines.

Big Water Tank – 30,000l Installation Guide and Warranty

Delivery and Moving:

Delivery of your Big Water Tank is to the entrance of your property. However, our driver has the discretion to deliver onto your site, provided that you have cleared a large access way.

An able-bodied person must be available on-site to assist with tipping the tank off the trailer.

Should you need to move your tank, empty it first and use a 1m long, 4×4 timber with a strap through the manhole. Lifting lugs can be supplied with the tank at an additional fee. A spreader bar or long straps (at least the diameter of tank) must be used to prevent excessive forces from squashing the tank. Contact BWT for guidance before moving your tank.

Site Preparation:

Remember that Big Water Tanks are for ambient temperature, potable water storage only. Site preparation is the responsibility of the purchaser. Contact BWT should you have any questions.

  • The site needs to be level and cleared with no rocks or materials that can damage the base of the tank and be able to support loads of at least 31 metric tons.
  • If the site is filled, please ensure adequate compaction for loads of at least 31 metric tons.
  • The area that supports the tank should be at least 200mm larger than the tank’s base diameter e.g.:
  • Our 30,000 litre tanks have a 3780mm base diameter
  • The support area’s diameter should be 4m
  • 100mm layer of GAP7 or “crusher” (see A) should be used as a bed for the tank
  • Prevent material washout e.g. with 100×50 timber (see B)
  • Drainage is critical for a buried tank (max 700mm) to prevent uplift (see C):
  • Install a perforated drain coil around the base of the tank;
  • Direct the drain outflow to a lower lying area; and
  • Buried tanks must also be backfilled with bark.
Plumbing:
  • A flexible hose must be used to connect to the base of the tank (see D)
  • Please note that polyethylene or alkathene pipe is not flexible
  • Stormwater pipes should be installed into the dome (see E)
  • Use an upside-down 45-degree Y junction, vented at the top
  • The straight leg is plumbed from ground level
  • The 45-degree leg, tank inlet should be sealed with a rubber tank seal
  • PVC Stormwater pipes should not exceed 150mm
  • The overflow must be greater than or equal to the inlet pipe size using a Y junction as described above and the outflow must be directed away from the tank base (see F)
20-Year Warranty:

Big Water Tanks Ltd (BWT) warrants to the original purchaser that the tank will be free from material defects arising from the manufacturing process for a period of 20 years from the date of purchase and BWT may, at its sole discretion replace or repair a defective tank during that period subject to the following conditions.

The warranty is void if it is not registered or if the tank: is not installed correctly; is not used for ambient temperature, potable water storage only; base support degrades or washes out; is moved or handled incorrectly e.g. with any water in it; degrades due to bad weather, earth movement, trees, roots, fire or vermin; or if the original purchase receipt is not kept.

The following are excluded from the warranty: inlet and outlet fittings; colour changes over time; removable lids; reasonable weathering; consequential losses or damages including but not limited to any damage to buildings, production, or the like; and any damage to the dome of the tank.

Any defect must be reported to BWT within 5 days of occurrence with
photographs showing the defect.

The warranty must be registered by the submission of photographs to BWT within 90 days of installation or any subsequent installation, clearly showing the that the tank has been installed correctly in
accordance with the instructions below. Include detail of all pipe-work, vents, base material, flexible outlet hose, backfilling, drainage, etc. Photographs must be submitted on the warranty page of the BWT
website https://www.bigwatertanks.co.nz/, or by email.

 

TANK SITE PREPARATION, INSTALLATION AND USE INSTRUCTIONS
FOR A 10,000 – 30,000 LITRE TANK

  • Advise RX Plastics Ltd immediately of transport damage prior to siting and installing your tank;
  • It is the responsibility of the purchaser to ensure the tank is installed correctly using the guidelines supplied by RX Plastics Ltd and best plumbing practice;
  • Select a site that is flat and level;
  • The foundation (4) can be made from concrete; sand; crusher dust or compact native soil, measuring approximately 100mm deep and 600mm wider than the tank base. All bases (except concrete) must be supported to prevent erosion from wind, water and any other factor;
  • On sloping ground, ensure actual tank site and surrounding area are level and that the area will remain free from any possible erosion damage in the future;
  • RX Plastics Ltd DO NOT recommend that any RX Plastics tank is buried;
  • Immediately after delivery, secure the Tank by either tying down with rope (avoid over tightening) or partially filling with water, approximately 300mm depth. NOTE – DO NOT attempt to lift a tank containing water – it must be completely drained before moving;
  • RX Plastics require an overflow to be fitted. Ensure that the overflow does not erode the foundation. Overflow can be fitted in one of the panels beside the manhole (3). Minimum recommended overflow size is 90mm (subject to inlet size);
  • Ensure all pipe work from the tank is supported to reduce stress on the tank. Use flexible pipe (1) or bellows on all pipe work to allow the tank to expand and contract (Up to 100mm). NOTE – PE pipe is not considered flexible;
  • To avoid the possibility of internal pressure; vacuum or heat build-up (when empty or full), a vent (5) must be installed. A recommended vent of 100mm is required for AS/NZS 4766 certified tanks. Always seek advice from tank manufacturer before installing;
  • Any tank with an outlet (2) that is over 50mm BSP is not certified to AS/NZS4766;
  • Any tank with an outlet (2) exceeding 100mm in the lower section of the tank wall will NOT be covered by the RX Plastics warranty;
  • Cleaning of tanks is advised if used for potable water supply. Seek advice from specialist tank cleaning company;
  • Ensure any fittings that may be screwed into the tank are not cross threaded and are not overtightened to avoid leaking;
  • No unauthorised repairs, modifications or alterations should be undertaken without prior written approval from RX Plastics as this will void the warranty;
  • RX Plastics Ltd do not recommend entering the tank for any reason, but if required follow MBIE guidelines on confined spaces entry before and during the procedure;
  • Heavy, unsupported loads are not permitted on the tank dome or wall – this includes standing on the dome under any circumstances or unsupported pipework.

NOTE – to view the Tank Warranty conditions go to RX Plastics Ltd website – www.rxplastics.co.nz/tanks.

SITING INSTRUCTIONS FOR WATER TANKS

Our tanks are delivered using our trucks each with a 15 tonne crane positioned at the back of the deck. The site for the truck to park to offload must be level and allow for the truck to back up to the tank site. The truck must then be able to put out the outrigger/stabilising legs to extend a total of 8.5 metres. The stabiliser legs can not be put onto fill, they must be supported by solid ground. The truck cannot unload off the side or on uneven ground. The crane is able to reach out approximately 2.5-5.0m from the rear of the truck depending on tank model and size and only if these conditions have been met.

Please make sure:

  1. There are no overhead wires, branches, gate posts, etc blocking the access of the loaded Tank and Truck. The driver will take as much care as possible not to damage property but will not be held accountable for damage due to restricted access.
  2. The ground is firm enough for the truck. Make sure there are no holes, drains etc to fall into. If you have a wet site please have a digger or appropriate machinery on site.
  3. Siting requires a level site and a good foundation so that all the weight is distributed evenly on solid ground. The truck will not be stable on fill. Please ensure the digging material has been placed so that the truck can access the site.
  4. Crane legs must be able to be extended on flat level ground that is solid virgin country – not fill, preferably in accordance with NZS 3604.
  5. Each tank pad should be on level good ground with roughly 75mm of evenly spread uncompacted bedding fines such as Pap7. (Sand should only be used if it is captive or it will likely wash out and undermine the tank over time). If good ground cannot be achieved, a base of compacted aggregate will need to be installed before the bedding fines are added.
    1.  

Please have your site prepared for our truck as we allow 30 minutes per tank on site.

Please note: Site preparation is the purchasers’ responsibility however we happy to carry out a site visit prior to delivery to assist in your preparation. Any site work carried out by our company will be charged additionally.

SITE PREPARATION

When preparing your tank site you should allow approximately 4.0m x 4.0m for each tank pad.

For a two-tank site we need to either ‘Tee’ the truck onto the length of it (Good ground required) or we will need to access from either end.
Instances where the ground or access is problematic and we can only access from one end, each hole may need to be prepared and tank installed separately as we cannot reach two tank lengths from one end of an 8.0m hole. In these instances, please allow for additional site time to be charged.

Each tank pad should be on level good ground with roughly 75mm of evenly spread uncompacted bedding fines such as Pap7. (Sand should only be used if it is captive or it will likely wash out and undermine the tank over time). If good ground cannot be
achieved, a base of compacted aggregate will need to be installed before the bedding fines are added.

MANUFACTURING STANDARDS

Absolute Concrete Water Tanks are manufactured to standards NZS 3106 and use material that conform to NZS 3422 and NZS 3109:1997. They are manufactured using high strength concrete and fabricated circular steel reinforcement (welded steel mesh) not
fiber like some other manufacturers. This helps to achieve a water tank suitable for a range of installations. The tanks have lifting anchors cast into the concrete walls.

Standard water tank lids may be installed to ground line and concealed with a maximum of 100mm of light free draining material such as bark, scoria or mulch. (Optional lid seals and manhole risers are required for this kind of installation). Standard lids are designed for pedestrian traffic only.

Heavy Duty Tank Lids are optional and a heavy-duty lid may be completely buried up to 200mm underground and still take light loads such as pedestrian traffic and mowers. We do also have options for vehicle surcharge if required. The HD lids are assembled
and sealed on delivery. After installation of a buried water tank we advise that you make sure it is at least half filled with water before backfilling. Where there is enough fall, tank holes should be permanently drained to avoid floatation. Anti-floatation bases can be provided where high water tables are present.

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