User Manual
24
START-UP AND OPERATION OF THE SOLAR 
PUMP STATION 
Observe the following safety instructions when starting up 
the solar thermal installation:
CAUTION
Solar thermal installations cannot be completely 
emptied after flushing. There is a danger of frost 
damage if water is used for flushing. Only use 
water to flush the system when the outside 
temperature is above 32° F, otherwise use the 
solar fluid to flush making sure to filter any 
debris before final filling. 
Use a water / propylene glycol mixture as a solar 
fluid (maximum 50% propylene glycol).
LEAK DETECTION  
1.  Disconnect the expansion tank from the solar system by 
unscrewing the nut on the tank connector. This prevents 
the access of dirt particles present in the pipes from 
entering the expansion tank.
2.  Remove the front cover of the solar station and the 
temperature gauges from the ball valves (a, b)
3.  Turn the two isolation ball valves (a,b) to 45° using an 
appropriate wrench to allow flow in both directions. 
4.  Close the drain valve (h).
5.  Be sure the air vent at the collector array is closed.
6.  Connect an air pressure hose to the fill valve (d) above 
the pressure gauge (e) and open this valve.
7.  Using an air compressor or pressurized air tank fill the 
system with pressurized air until the pressure gauge 
(e) reads 40 psi then close the fill valve (d).
8.  The pressure should hold steady for 15 minutes. If 
the pressure falls it is an indication of a leak. Find and 
repair the leak then repeat steps 6 and 7 watching 
for the pressure to hold at least 15 minutes. After the 
pressure test slowly open the drain valve (h) to release 
the air pressure on the system. 
FLUSHING 
9.  Disconnect the air pressure hose from the fill valve (d)
10.  Connect a water hose from a water source with at least 
40 PSI supply pressure to the fill valve (d).
11.  Connect a discharge hose to the drain valve (h) and 
open this valve. Place the other end of the discharge 
hose into an appropriate drain.
12.  Turn the supply ball valve (b) to 90° (horizontal) so that 
the valve is closed.
13.  Turn on the supply water and open the fill valve (d) 
then leave running for 15 minutes to flush debris out 
of the solar loop
14.  After the 15 minute flush turn off the supply water at the 
source and allow the system to drain. When water stops 
flowing out of the discharge hose close the fill valve (d)
15.  Close the drain and fill valves (d & h) on the pump 
station and disconnect the water source hose.
FILLING  
The storage tank loop is filled with potable water by means 
of the valves and fittings of the storage tank.
16.  Fill the storage tank following the procedures in the tank 
section of this manual.
17.  Vent the storage tank loop by opening a nearby hot 
water faucet and the storage tank loop ball valve (A) 
to avoid trapped air in the storage tank loop of the 
pump station and burn out of the water heater heating 
element. 
18.  Close the faucet and solar loop air vent (A) after all 
air has been purged and the water comes out with 
constant flow.
PREPARATION OF THE HEAT TRANSFER FLUID 
19.  Pour 100% Propylene Glycol into a large clean bucket. 
Add an equivalent amount of distilled or de-mineralized 
water for a 50/50 solution by volume.
The use of regular tap water as a mixing agent is 
prohibited. Distilled or de-mineralized water is often 
available from grocery stores and drugstores. This 
solution provides freeze protection down to -30° F and 
burst protection down to -60° F. 
Use of heat-transfer uid other than a maximum 50/50 
mix by volume of Propylene Glycol and distilled or de-
mineralized water is not permitted. Use of any heat-
transfer uid other than that specied by the appliance 
manufacturer will void warranty, and may result in poor 
performance, equipment damage, or risk to health and 
safety.
FILLING THE SOLAR LOOP 
20.  Connect a discharge hose to the drain valve (h) and 
place the discharge end of the hose into the glycol 
solution container.
21.  Turn the return ball valve (a) to 0° (vertical) so that flow 
is only allowed in the proper direction.
22.  Connect a fill hose from the glycol container to a 1/2 










