3.1 Hot Gas Valve
The hot gas valve is used to bypass the capillary tube and send warm gas to the
evaporator when opened during the harvest cycle. The valve is actuated by a solenoid
that opens the valve when energized and closes when de-energized. The valve seats using
gravity so the valve must remain vertical to fully close.
A faulty hot gas valve will result in long ice production cycles and higher than normal
low side pressures. The valve usually fails by being stuck in the open or closed position,
or by not fully seating in the closed position causing the valve to leak-by. A
contaminated system or damage to the valve body will cause any of these failures. Care
in keeping the system clean, handling the valve, keeping the valve cool during brazing,
and evacuation of the system before charging must be done to prevent damage and
eventual failure of the valve.
Figure 3-2
Figure 3-1
A quick way to check the valve to see that it opens and closes freely (with the system still
sealed) is to repeatedly energize and de-energized the solenoid and listen for the valve
opening and closing. You should be able to hear a distinct “click” of the valve opening
and closing. If you cannot hear this, then the valve is stuck and will need to be replaced.
The solenoid coil itself can be check be measuring resistance across the electrical
terminals. A resistance reading of 380-390 ohms should be found in a good solenoid
coil.
Replacing the hot gas valve.
Removal:
1. Disconnect power, water line, and drain line. If a drain pump is used, it will need to
be disconnected and removed.
2. Remove the access panel and rear panel (see figure 3-3).
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