6
APP-001f
SEPT 2016
An indication of proper operation of the metering valve is
a frosted liquid feed line from the metering valve to the
low-pressure liquid-return line. If the line is not frosted
when the purger is in COLLECTING AIR/WATER mode, then
the flow of refrigerant through the line may be blocked
due to dirt in the metering valve or strainer.
The metering valve is set and held in place by a locking
knob. Unlock this knob using the .035” hex key wrench
provided inside the purger control cabinet. To clean the
orifice of the metering valve, fully open the metering
valve to flush out any particles. Then, close the valve and
reopen two turns.
If the line still does not frost, then pump out the purger
and inspect the strainer and metering valve.
HIGH SIDE TO LOW SIDE BYPASS VALVE
The High Side To Low Side Bypass Valve is normally
closed. The AUTO-PURGER Plus has portions that
normally contain high pressure, and portions that normally
contain low pressure. The two portions are separate and
isolated from each other. For some maintenance and
testing purposes, it may be desirable to connect the two
together so that the pressure in both is the same. The
High Side To Low Side Bypass Valve may be opened for
these purposes. Return this valve to its closed position
for normal operation, see Figure 5.
WATER BUBBLER
Noncondensible gas released from the AUTO-PURGER
Plus flows through the water bubbler where residual
ammonia is absorbed into the water. Large, 1” (25 mm)
diameter bubbles in the water bubbler indicate proper
operation. The water, with absorbed ammonia, flows to a
drain. The water bubbler fill line solenoid valve (D) opens
to automatically replenish water to the bubbler each time
the purge gas solenoid valve (C) energizes. The water
bubbler fill line solenoid valve (D) remains energized
for 30 seconds after the purge gas solenoid valve (C)
de-energizes (float switch magnet pulls in). This fills the
water bubbler with fresh water for the next purge cycle.
LIQUID DRAINER
The liquid drainer separates any liquid condensed in the
purge point piping. This liquid is fed to the low-pressure
liquid return line. Therefore, only foul gas—no liquid—
enters the condensing section of the purger. However,
if too much liquid comes down the foul gas line due to
improper piping, corrective action must be taken.
VAPOR TRAP
The vapor trap separates any vapor that flashes in the
low-pressure pumped liquid line piping. This vapor is
fed to the suction line. Therefore, only liquid—no vapor—
flows through the liquid make-up solenoid valve (B) to the
evaporator chamber of the purger.
CHECK VALVES
There are five check valves on the purger.
a) 1 psid (.07 bar) check valve with a 1/32” (.8 mm) diameter
metering orifice is installed on the purge gas line to
prevent reverse flow of water into the purger from the
water bubbler.
b) 225 psid (15.5 bar) relief check valve from the float
chamber to suction line.
c) 1 psid (.07 bar) relief check valve from the suction line
to the float chamber.
d) 1 psid (.07 bar) check valve in the water purge line to
prevent reverse flow of water into the purger from the
customer supplied container.
e)The water bubbler fill line has a ½” check valve.
PURGE GAS ORIFICE
A metering orifice disc is installed inside the 1 psid (0.07
bar) check valve in the purge gas line to the water bubbler,
see Figure 6. This 1/32” (0.8 mm) diameter orifice meters
the noncondensible gas into the water bubbler to prevent
over or under feeding. The ¼” NPT gauge valve should
be fully open during operation and closed for pump out
or maintenance.
METERING VALVE
The metering valve meters condensed liquid refrigerant
from the high-pressure float switch chamber of the purger
into the low-pressure liquid-return line. The refrigerant
is filtered through a small flanged strainer prior to the
metering valve, which removes any particles that might
block the orifice.
PURGE GAS SOLENOID VALVE
Figure 4
1/4" PURGE GAS GAUGE VALVE
WIDE OPEN DURING OPERATION
CLOSED FOR SERVICING PURGER
PURGE GAS
1/32" (0.8 MM) DIA
METERING ORIFICE
(0.07 BAR)
PURGE GAS TO WATER BUBBLER OR
TO CUSTOMER SUPPLIED WATER BOTTLE
CHECK
VALVE
SOLENOID VALVE
DISC INSTALLED IN
THE CHECK VALVE
1 PSID
SECTION 3 COMPONENT DESCRIPTIONS
