15
c l i m a t e m a s t e r.c o m
Tranquility
®
22 Digital (TZ
)
Series - 60Hz
R e v. : N o v e m b e r 1 8 , 2 0 2 2
Flushing the Earth Loop, Cont’d.
Figure 15b: Valve Position B – Unit Fill/Flush
Loop
Valve Position
Out
In
Flush Port
Front of Unit
Valve Position
UNIT FILL
Unit fill valves should be switched to Position B while flush
cart is pumping to fill the unit heat exchanger (see Figure
15b). The valves position should be maintained until water is
consistently returned into the flush reservoir.
LOOP FLUSH
Switch to valve Position A. The supply water may be shut
off and the flush cart turned on to begin flushing. Once the
flush reservoir is 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 can not
be continuously mixed back into the fluid. Surges of 50 psi
[345 kPa] can be used to help purge air pockets by simply
shutting off the flush cart return valve going into the flush
cart reservoir. This process ‘dead heads’ the pump to 50 psi
[345 kPa]. 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 all air is purged from the system, the level
will drop only 3/8 inches in a 10 inches [25.4 cm] diameter
PVC flush tank (about a half gallon [1.9 liters]) since liquids
are incompressible. If the level drops more than this level,
flushing should continue since air is still being compressed in
the loop fluid. Do this a number of times.
NOTICE:
Actual flushing time require will vary for each
installation due to piping length, configuration, and flush
cart pump capacity. 3/8 inches or less fluid level drop is the
ONLY
indication that flushing is complete.
Switch valves to Position B to flush the unit. Flush through
the unit until all air pockets have been removed.
Move valves to position C. By switching both valves to this
position, water will flow through the loop and the unit heat
exchanger. Finally, the dead head test should be checked
again for an indication of air in the loop. Fluid level drop is
your only indication of air in the loop.
Figure 15c: Valve Position C – Full Flush
Loop
Valve Position
Dead Head
Pump Test
for Air
Add Antifreeze
Now if Needed
Out
In
Flush Port
Front of Unit
Valve Position
PRESSURIZE AND OPERATE
As shown in Figure 15d, close the flush cart return valve to
pressurize the loop to at least 50 psi [345 kPa], not to exceed
75 psi [517 kPa]. Open the isolation valve to the expansion
tank and bleed air from the expansion tank piping using the
schrader valve located in front of the expansion tank. This
will allow loop pressure to compress the expansion tank
bladder, thus charging the expansion tank with liquid. After
pressurizing, close the flush cart supply valve to isolate the
flush cart. Move the Flow Controller valves to Position D.
