FORM 155.32-ICOM2.EN.UL
SECTION 7 – MAINTENANCE
ISSUE DATE:1/10/2018
JOHNSON CONTROLS
127
MANUAL METHOD TO PURGE NON-CONDENSABLE GAS DIRECTLY
FROM ABSORBER
When the chiller-heater operates at a lower capacity than usual for a long period of time or
when it restarts after a power failure, the absorber may contain non-condensable gases. If
the machine starts under these conditions, the unit performance and efficiency decrease. If
this happens, purge non-condensable gas directly from the absorber manually as outlined
in the following procedure.
1. Set the valves according to Pattern B, see
.
2. Press the Purge Mode
Manual
button on the Setting screen.
3. Press the Manual Purge
ON
button. The vacuum pump starts. The solenoid valves
SV1 and SV2 open.
4. After step 3 begins, confirm that vacuum gauge stands at 0 ~1 kPa.abs.
5. Reading the vacuum gauge, open valve V13.
6. Then, open valve V16 gradually. Confirm that the pressure on the vacuum gauge in-
creases slightly.
7. If no problems are found, open valve V16 the rest of the way.
8. Continue to purge for 2 to 3 hours.
9. Close valves V13 and V16.
10. Press the Manual Purge
OFF
button. The vacuum pump stops.
For information on how to set up an automatic purge, see
Automatic Method to Purge Non-
condensable Gas from the Purge Tank on page 128.
NOTE: If the pressure decreases when valve V16 opens, the vacuum pump capacity is
too small. Close valve V16 at once and check the purge line.
NOTE: Make sure the valve is completely open.
