Technical data

iv. Open the valve V1 to the heat pump and start the purge pump to circulate the antifreeze around the

system. Leave the pump running until antifreeze is seen returning to the dustbin. The amount of

time this will take depends upon the length of the header pipe.

v. Close the valve to the heat pump and turn the purge pump off.

vi. Open the first slinky flow and return valve and with the return pipe inside of the dustbin start the

purge pump. Once the return discharge runs clear, i.e. It’s discharging fresh water, move the return

pipe out of the dustbin and discharge this fresh water to drain until the antifreeze level within the

dustbin drops to approximately 200-250mm. Take care that the suction pipe remains covered with

water to stop any air being admitted into the system. (Depending on the length of header pipe addi-

tional antifreeze might be required to be added at this stage). The discharge pipe can then be placed

back into the dustbin and the purge pump should be run for about 5-10mins and then turned off.

vii. Close the slinky valves; add the next quantity of antifreeze to the dustbin and repeat the above steps

vi and vii for each individual slinky.

i. Open all valves EXCEPT THE DISCHARGE PURGE CONNECTION. Keep a close eye on the level of water

in the dustbin and start the purge pump. This should pressurise the whole system. If the level of

water drops significantly this indicates the system hasn’t been correctly purged of air and needs to

be re-purged.

ii. Close the fill purge valve on the slinky manifold with the pump running, so that the ground array is

left under pressure.

iii. Most purge pumps will attain around 5 bar, and the circuit should be left at this pressure for a

minimum of 15 mins, as any leaks will become immediately apparent. The pressure will slowly fall as

the pipes in the ground arrays slowly expand in the coming months, and may need topping up using

the cold fill system provided.

iv. Remove the purging equipment. Replace the plastic blanking plugs in the slinky manifold purge

connections.

There should be approximately 200-250mm of water/antifreeze mix within the dustbin which can be

poured back into an empty drum and disposed off according to the disposal instructions in section 8 or

retained for topping up the system.

To mix the antifreeze around the ground arrays thoroughly, it is advised that the ground array circulation

pump is turned on via the 4 amp MCB on the heat pump. (Note DO NOT TURN THE COMPRESSOR 25 amp

MCB ON). This ground array circulation pump should be left running for two to three hours to ensure the

antifreeze is mixed in all the slinkies and the heat pump. (Note: - the floor pump will also run.)

5.1.3 Purging Procedure and adding antifreeze for single slinkies

The single slinky manifold consists of two three port diverting valves, one for flow and one for the return.

The manifold allows the slinky to be filled and purged.

Fig 25 Single Slinky

Manifold

5.1.2.1 Pressurising the system.

To/From Heat Pump 28mm OD

To/From Slinky 28mm OD

Return Purge/Fill Connection Return Purge/Fill Connection