Specifications

GT-PCS Split Units - 60Hz Puron
®
Created: 29 Aug., 2013
16
Multiple Unit Piping and Flushing - Indoor Split (50YGS Only)
Water Out
Water In
Heat Pump
Water Out
Water In
Heat Pump
To Ground
Loop
Water Out
Water In
Heat Pump
Pump
Isolation
Valves
Ground Loop
Shut-Off Valve
Flush
Valve
Pump
Exp
Tank
Size for
Heat Pump
‘B’ Flow
Size for Heat Pump
‘A’ Flow
Size for ‘A’ + ‘B’ Flow
Size for ‘A’ + ‘B’ + ‘C’ Flow
Size for
Heat Pump
‘C’ Flow
Figure 9c: Multiple Units with Internal Modulating Valves and Central Pump
Multiple Units with Internal Modulating Valves and
Central Pump
This is an application where multiple units are used in
conjunction with a central, variable speed pump. In this case,
units with closed loop modulating valves are used (do not
use open loop modulating valves on a closed loop system).
External fl ushing valves are required. This application is for
larger systems, including commercial.
Before fl ushing, the installer should manually open all
modulating valves as detailed in Closed Loop – External
Central Pumping section of this manual. Next, fl ush the
ground loop. The installer should close a pump isolation
valve and open the ground loop shut-off valve to prevent fl ow
through the indoor loop while fl ushing the ground loop.
Once the ground loop is fl ushed, close the ground loop
shut-off valve and open the pump isolation valve to fl ush
the units and indoor piping. Once the system is fl ushed
remember to return the modulating valves to their normal
operating position.