9
Ground Source Heat Pumps Since 1983
THE FILLING AND DE-AERATION PROCESS OF
T 21-31 / P 21-31
Please check that the ground loop has been correctly connected (see “Connecting the ground loop” section) and that
the compressor has been preheated (see ”Safety precautions” section).
1. Install filling and de-aeration assemblies to the collector pipe (return) according to the picture beside
2. Attach textile hoses to filling unit
• Attach a textile hose from submercible pump to the filling unit (nr 2)
• Attach the textile hose from filling unit (nr 3) to the mixing tank.
3. Fill the container with a geothermal fluid mixture (ethyl alcohol water 1:1 or glycol)
4. Open filling unit valves (nr 2 and 3) and close the shutt-off valve (nr 1)
5. Turn on the submercible pump.
6. Add water and ethyl alcohol mixture to the mixing tank until no more fluid can enter the pipes.
7. Use the brine pump of the ground source heat pump to accelerate the circulation.
• Turn the main switch (Q1) and the heating switch (S2) on.
• Turn the switch S4 (Auto - 0 - Maalämpö) to the position 0 (compressor running prevented).
• Check that motor protection switces (QM1, QM2) are on.
• Turn the control current (F3) on. The brine pump starts. Check the rotation direct of the brine pump by
using the switch S2.
Keep the submercible pump running until the fluid is clear and no gurgling can be heard from the pipes. Please note!
Deaeration usually takes several hours and helps ensure that all the air is removed from the system and that there are
no malfunctions once the system is started. LEAVE NO PRESSURE IN THE NETWORK!
8. Turn pumps off.
9. Close filling unit valves (nr 2 and 3)
10. Remove textile hoses.
11. Clean the ball valve with integral filter of both collector loops.
12. Open the valve nr 1.
13. Fill the expansion tank with ethyl alcohol m ixture (2/3 capacity)
14. Install the safety valve to the top of the expansion tank.
Filling and deaeration have now been completed. Install the expansion tank, if the collector pipe is planned to be
pressurized. PLEASE NOTE! Once the heat collecting pipes have been placed in a bore well, we would advise users to
switch the positions of the textile hoses in the group of fill valves during filling and deaeration. This increases the effi-
ciency of the pipes.
2.5. Boiler connection
Connect the boiler to the ground source heat pump accordingly the HWAC drawings (chapter 6). The connection may
vary depend on the boiler type. It is needed to add a trim valve to reduce superheat circuit flow. The factory setting for
trim valve is fully open. Close the valve at first. Then open the valve to the right position according to the following
table. It is possible to tune the amount of superheat according to the need afterwards.
Heat pump
T 10
T 13
T 15
T 21
T 31
Adjustment of trim valve
open 1 round
open 1 round
open 1 round
open 2 rounds
open 2 rounds
1
3
2
4
