17
APP-001b
APR 2007
CONTROL CONSOLE DISPLAYS 4444
PURGED OVER 60 MINUTE TIME LIMIT.
If noncondensibles
are released from the purger for 60 minutes continuously, a
time delay will close the purge gas solenoid valve (C). This
limits the possibility of a substantial amount of refrigerant
inadvertently being released into the water bubbler in the
unlikely event of purger malfunction.
R E ASO N 1:
A large volume of noncondensibles is
continuously being removed from system.
Action:
Reset the time delay by pressing the RESET 4444
functional pushbutton on the Control Console. See
Figure 5. Delay is now reset for up to another hour of
continuous purging. Otherwise, put the purger in New
System Star t-up mode for continuous purging without
the 60 minute time limit.
REASON 2:
Purge gas solenoid valve (C) is not opening
or the removable seat/orifice is blocked.
Check:
Make sure purge gas solenoid valve (C) is energized.
If not, check for voltage at solenoid coil.
Action:
Replace the coil if it is burned-out, otherwise
clean or replace the valve. See also the Caution section
on page 19.
REASON 3:
The shut-off valve located before the purge
gas solenoid valve (C) is closed.
Check:
Verify that purge gas is not being sent to the
bubbler.
Action:
Open the valve.
CONTROL CONSOLE DISPLAYS 7777
LOSS OF LOW-PRESSURE PUMPED-LIQUID.
If the
liquid line solenoid valve remains energized for more than
30 minutes, it indicates there is insufficient low-pressure
pumped-liquid available to maintain an adequate level in
the flooded evaporator of the purger. The purger will not
purge air until this is corrected.
REASON 1:
Liquid line solenoid valve (B) is not opening
or the seat/orifice is blocked.
Check:
Make sure the liquid line solenoid valve (B) is
energized. If not, check for voltage at the solenoid
coil.
Action:
Replace the coil if it is burned-out, otherwise
clean or replace the valve. See also the Caution section
on page 19.
REASON 2:
Liquid line restricted.
Check:
Look for closed shut-off valves in the pumped-
liquid line, plugged strainers, or the plastic shipping
cap still in the liquid line flange.
Action:
Inspect piping for a closed shut-off valve. Open
the shut-off valves, clean the strainer, or remove the
shipping cap. See also the Caution section on page
19.
NONCONDENSIBLES ARE NOT BEING
RELEASED.
(See also page 16; Control Console displays 3333)
REASON 1:
Noncondensibles not present in system.
Check:
Compare the refrigerant liquid temperature from
condenser exit with the condensing pressure. The
pressure/temperature relationship should be within 2
or 3 psig (0.14 to 0.21 bar).
Action:
None at this time.
REASON 2:
Metering valve plugged.
Symptom:
The purger appears to be operating properly,
however, the low-pressure liquid-return line is not
frosted.
Check:
Fully open the metering valve to flush out any
par ticles. Then, close the valve and reopen two turns.
REASON 3:
“Foul gas” line is flooded with liquid.
Symptom:
The line from the bottom of the liquid drainer
often remains frosted.
Check:
Inspect condenser and “foul gas” piping. In many
cases, the problem is liquid refrigerant being drawn
from the purge point. To prevent this from happening,
select purge point locations above liquid sur faces and
make sure purge point lines are installed so that only
vapor, and not liquid, can be drawn in. Refer to Piping
Instructions in Section 2 of this bulletin.
Action:
Correct condenser and “foul gas” piping.
AMMONIA INSTEAD OF NONCONDENSIBLES
RELEASED FROM PURGER.
REASON 1:
Purge gas solenoid valve (C) leaking at
seat.
S y m p to m :
A slow leak of noncondensibles to the
bubbler.
Check:
Look for dir t or a worn seat in the purge gas
solenoid valve (C).
Action:
Remove, clean, or replace the solenoid tube
plunger or valve. See also the Caution section on
page 19.
REASON 2:
Oil in purger.
Symptom:
No frost around the low side oil drain valve.
Action:
Remove oil through both the low side and high
side drain valves (See Figure 1) per safe refrigeration
procedures. See also the Caution section on page 19.
WATER BUBBLER DEVELOPS EXCESSIVE
MINERAL COATING.
REASON 1:
Hard water.
Action:
Add vinegar to the bubbler water. Then, clean with
the supplied brush. Use a water conditioning housing
and car tridge in the water supply line to the purger.
