FHP EV Series Installation And Maintenance Manual - page 9
9
EV SERIES
present in the return line, flow should be reversed. This
procedure should be repeated several times until no air is
present. If air is left in the loop, it will have an immediate
effect on the unit’s coaxial heat exchanger causing
corrosion of it and any associated ferrous metal
components. It is absolutely imperative that the system is
clean and completely free of air.
3.
With the flush cart running, close BV1 and BV4.
This will create a positive pressure on the loop and the
flush cart may be shut off. It is important to close the
valve on the outlet side of the loop (BV4) first to obtain
this required positive pressure.
4.
The heat pump also requires purging. With all valves open
repeat steps 2 and 3. For normal heat pump operation,
open valves BV2 and BV3, close valves BV1 and BV4.
Replace caps in purge connections.
OPTIONAL HEAT RECOVERY PACKAGE
WATER PIPING:
All hot water piping should be a minimum of 3/8” O.D. copper
tube to a maximum distance of fifteen (15) feet. For distances
beyond fifteen feet but not exceeding 60 feet, use 1/2” copper
tube. Separately insulate all exposed surfaces of both
connecting water lines with 3/8” wall closed cell insulation.
Install isolation valves on supply and return to the HR unit.
IMPORTANT NOTE: The water from the HR unit may be in
excess of 140º F. Local codes may require a mixing valve in
the hot water system to prevent water in excess of 120ºF from
reaching a faucet. This valve is not part of the HR package
and should be installed separately.
HR START UP:
1.
Make sure all valves in the heat recovery water piping
system are open. Never operate HR Pump dry.
2.
Turn on the heat pump. The HR Pump should not run if
the compressor is not running.
3.
Turn the HR switch to the “ON” position. The indicator
light will illuminate indicating pump operation if the
entering water temperature is below 140º F.
4.
The temperature difference between the water entering
and leaving the heat recovery unit should be between 5º
to 15º F.
5.
Allow the unit to operate for 20 to 30 minutes to ensure it
is functioning properly. The pump should shut off when
the water temperature entering the heat recovery unit
reaches approximately 140º F.
BV3
BV4
LOOP
PURGE OUT
CONDENSER
WATER OUT
BV1
LOOP
PURGE IN
CONDENSER
WATER IN
BV2
PUMP
HEAT
EXCHANGER
(Figure #9)
VALVE POSITION DIAGRAM
(Figure #10)
TO PURGE LOOP:
BV1 - OPEN
BV2 - CLOSED
BV3 - CLOSED
BV4 - OPEN
TO PURGE HEAT PUMP: ALL VALVES OPEN
TO OPERATE SYSTEM:
BV1 - CLOSED
BV2 - OPEN
BV3 - OPEN
BV4 - CLOSED
REPLACE CAP PLUGS AFTER PURGING.
UNITS SHIPPED WITH VALVES SET IN
“LOOP PURGE” POSITION