CHi  BOOSTER  SETS

All the water you could possibly want, and spare

The DPS CHi Booster Sets have been designed to get around problems of poor water supply or pressure. They can provide enough water to supply the largest of properties, and allow the use of multiple bathrooms, high pressure body jets, large shower roses, and what ever else takes your fancy.

The pump set does require connection to a cold water storage tank, fed from the mains.  This needs to be sized to meet the water demands of the house, taking into account the water feeding in from the mains, and can be located anywhere above the pump set.  

The sets make use of two pumps, rather than just one, in order to improve the performance range, and to provide some redundancy.  It is important to use two pumps when designing the main water services to the property.  Should one pump ever fail, or need to be removed for cleaning, or replacement, the set will automatically continue to operate on the remaining pump. With only one pump the property would be without water.

Our approach to the controls for the pumps has been to keep it as simple as possible, while providing the basic set of functions that are necessary.  To ensure equal wear on both pumps, we have included auto-change-over controls, alternating which pump starts first each time. Both pumps will only come on together when the flow rate to outlets is high enough.  The controls also provide a visual indication of which pumps are running, the ability to turn off each pump, and pump-test buttons to allow each pump to be manually turned on.  

All wiring is at mains voltages, without the use of any transformers, PCBs, or microprocessors.  All logic is provided by standard relays, all of which are available from RS Components online where spares (should they ever be needed) can be ordered up to 8:00pm for next day delivery.  We have seen that this approach not only improves reliability, but also allows systems to be easily upgraded without specialist knowledge or difficult to obtain parts. 

To reduce wear on the pumps, the sets are supplied with a large 100 litre accumulator vessel.  This stores up high pressure water and overcomes the need for pumps to turn on just for small volumes of water.  

To ensure reliability  we have chosen Grundfos CHi stainless steel multi-stage pumps, well known as one of the best pumps money can buy,  and for ease of servicing we have fitted the set with quarter turn ball isolating valves and unions connections.  

Various models of CHi pump are available on request - see PDF

For added protection we supply a water level switch that is fitted into the cold tank and will cut out the pumps should the cold water tanks run dry.  Pump overload protection is also provided by the controls.

The set comes fully pre-assembled, and pre-wired, with the accumulator vessel supplied loose for site connection.  

  
The following photograph shows a typical pump set installation.  This set (an older design with a wooden base instead of the current metal frame) was used to provide the water supplies to a 6 bathroom farm property.  It was used in conjunction with a DPS Heat Bank Thermal Store to provide very high performance hot and cold services at balanced pressures, capable of driving all bathrooms simultaneously.  The set was located in the basement, and it was almost impossible to hear the pumps running from the room above.  

A note on pipe sizing:  At 180 litres per minute, the pressure lost in 28mm pipework will be 0.9 bar every 10m of pipework, however for 35mm it is only 0.3 bar.  Both result in water velocities over 3m/s, so for the main distribution pipes 42mm or 54mm pipe should be used when flow rates of 180l/m are expected.  35mm will be suitable for up to 150 litres per minute.

In order to keep cold tank sizes to a minimum,  keep all pipework from the mains to the cold tanks in full-bore main supply size or larger.  The best ball-float valves to be used are Equilibrium Float Valves. 

The size of valve to be used can be selected by testing the full flow rate of the mains into the tanks (without a float valve) and then pick the valve that will at least match this flow at a static pressure of 0.5 bar. (see table).  The lower the tanks, the better the flow into them should be.

The tank size needs to allow for the maximum amount of water that could ever be used in a period of time, less the volume measured coming in from the mains over that period. Allow some spare if possible. 

The Kit version of the booster sets are aimed at the more cost-driver customer, who is willing to assemble the unit themselves.  Can also be very useful if space is confined, and the standard pump set layout is not best suited.

Components supplied are as follows:

2 x Grundfos CHi Booster Pumps
2 x Pressure Switches
2 x Non-Return Valves 1¼"BSPF
4 x Full Bore Lever Isolating Valves 35mm
8 x Straight Connectors 35mm Compression to 1¼"BST
Pressure Gauge
Fully assembled control centre (wall mounted) with all cables fitted (3m long)
Assembly and Layout Instructions

The Accumulator Vessel needs to be ordered separately.

We have included all components that are either difficult to put together, source, or where it is easy to use the wrong off-the-shelf type.  Just about everything except pipe, elbows, tees and supports. 

  DEDICATED PRESSURE SYSTEMS LTD.   
Telephone 01372 803 675  Fax 01372 803 678   
Email dps@heatweb.com  Internet http://www.heatweb.com