W2W Series Heat Pump
Ecologix Heating Technologies Inc
Page
10
www.ecologix.ca
221 Holiday Inn Drive Cambridge ON
ph: 519-658-4330
and dirt particles from the loop itself. An
antifreeze solution is used in most areas to
prevent freezing. All air and debris must be
removed from the earth loop piping system
before operation. Flush the loop with a high
volume of water at a high velocity (2 fps in all
piping) both directions.
The steps below must be followed for proper
flushing. Fill loop with water from a garden hose
through flush cart before using flush cart pump
to ensure an even fill. Once full, do not allow the
water level in the flush cart tank to drop below
the pump inlet line or air can be pumped back
out to the earth loop. Try to maintain a fluid
level in the tank above the return tee so that air
cannot be continuously mixed back into the
fluid. 50 psi surges can be used to help purge air
pockets by simply shutting off the return valve
going into the flush cart reservoir. This
procedure ‘dead heads’ the pump. To dead head
the pump until maximum pumping pressure is
reached, open the valve back up and a pressure
surge will be sent through the loop to help purge
air pockets from the piping system. Notice the
drop in fluid level in the flush cart tank.
If air is
purged from the system, the level will drop
only 1-2 inches in a 10" diameter PVC flush
tank (about a half gallon) since liquids are
incompressible
. If the level drops more than
this, flushing should continue since air is still
being compressed in the loop fluid. Do this a
number of times.
When the fluid level drops less than 1-2" in a 10"
diameter tank the flow can be reversed. Finally
the deadhead test should be checked again for an
indication of air in the loop.
This fluid level
drop is your only indication of air in the loop.
Flushing & Filling Using 3-Way Valves
Step 1:
Use water and a high volume head circulator
pump to flush air and debris and to fill the loop
system.
- Refer to recommendations provided by
IGSHPA when choosing a pump for the flushing
process.
- It is recommended that pump suction be from
the bottom of a large volume container. Use a
suction line strainer to prevent debris discharged
into the container from being recycled to the
system.
Step 2:
Pump water into the system by connecting the
pump discharge hose to one (not both) of the 1”
NPT water connections located on the sides of
the 3-way flush valve. Connect a return hose to
the opposite side of the valve assembly to
discharge debris and air as water is added to the
loop.
Step 3:
Rotate the 3-way valves to engage the pump cart.
Step 4:
Start the pump. Add anti-freeze (if used) and
water to the container as needed so that no air
enters the system. This will push any air out of
the loop. If flushing assembly is equipped with
valves to reverse flow direction, do so
occasionally to help remove trapped air. When
bubbles cease in the return hose container, the
earth loop has been completely flushed.
Step 5:
Flush the heat pump. To do so, simply rotate the
valves while the pump is running. Flush the heat
pump using the same procedure as used to flush
the earth loop.
Pressurizing the System
Step 6:
After flushing and filling the system, rotate the
3-way valve discharging into the flush container
to pressurize the loop. Then turn the valves.
Step 7:
Turn off the flush cart pump. The system should
remain pressurized. Release excess pressure by
rotating either module valve to allow a small
amount of water to pass through and out of the
system and into the container. Some initial loss
of pressure can be expected and is due to the
expansion of the earth loop pipe under pressure.
The pressure will stabilize if the system has no
leaks.
Step 8:
Flushing, filling and pressurization should be
complete. Start the loop pump module
circulators.
Step 9:
Troubleshoot. If for some reason the circulators
are not operating, power off and diagnose the
problem.
