Filling The System & Purging Air - Sanden GS3-45HPA-US Installation Manual

Filling the System & Purging Air
The following steps must be taken to ensure all air is removed from the system.
Incorrect purging of air may cause the water temperature to vary during operation, and
lead to possible error codes.
 Ensure that all piping to tank unit and heat pump unit are installed and connections
are tight, then open the Cold Water Supply Valve to the system.
 Push up the lever on the PR valve to open, and fill the tank unit with water.
Confirm that water comes out of the relief valve, and then close the lever.
 Open the hot water faucets to remove air from the house piping system.
 Close the faucets after no air is seen in the water.
 Open the water drain plugs (two places) on the heat pump unit.
Close the plugs after no air is seen in the water or a steady stream of water is
present.
 Supply power to the heat pump unit and leave the hot water faucets open for 3
minutes. Close the faucets after no air can be seen in the water.
Figure 10: Air removal process
Sanden Heat Pump – Installation Manual
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