Start-Up After Limited Shutdown; Start-Up After Extended Shutdown; Start-Up After Below Freezing; Conditions - Carrier 16JT Series Start Up & Operation Manual

Start-Up After Limited Shutdown

1. Place the capacity control, Cycle-Guard,™ and Local-
Remote settings in the position indicated in Table 7.
Table 7 — Start-Up Setting Positions
SETTINGS
Capacity Control
Cycle-Guard Switch
Local-Remote Switch
2. Depress the Start button.
Machine should start in normal manner and the Run light
should be on. The refrigerant pump will start about 5 min-
utes after chiller starts; the solution typically heats up to nor-
mal operating conditions within 20 to 30 minutes.
If, however, machine does not lower leaving chilled water
temperature to design, noncondensables may be present. In
this case, take an absorber loss reading (see Maintenance Pro-
cedures, Absorber Loss Determination section, page 31).
If absorber loss is 5° F (3° C) or less, the chilled water
temperature should drop to design within a short period as
the automatic purge evacuates the machine. A completely
evacuated machine normally has an absorber loss of 2° F
(1° C) or less.
If absorber loss is greater than 5° F (3° C), follow the pro-
cedure for Start-Up After Extended Shutdown.

Start-Up After Extended Shutdown

1. Start the machine in the normal manner by placing the
capacity control and Cycle-Guard settings in the posi-
tions indicated in Table 7.
2. Depress the Start button.
When refrigerant pump starts and solution is warm (strong
solution approximately 100 to 130 F [38 to 55 C]), place
capacity control operation button in MANUAL position
and press the positioning button ( ) to shut the steam
valve.
3. Determine machine absorber loss (see Maintenance Pro-
cedures, Absorber Loss Determination section, page 31).
If absorber loss is 5° F (3° C) or less, open capacity con-
trol valve by placing capacity control button in AUTO.
position and allow machine to operate. The purge will
evacuate the machine to the normal absorber loss of 2° F
(1° C) or less.
If absorber loss is more than 5° F (3° C), evacuate ma-
chine to remove noncondensables that can prevent nor-
mal operation (see Maintenance Procedures, Machine
Evacuation section, page 33). An alternative procedure is
to limit steam pressure so that low-stage generator strong
solution temperature remains below 140 F (60 C) while
machine purge removes the noncondensables.
POSITION
AUTO.
AUTO.
AS APPROPRIATE
4. When absorber loss is reduced to 5° F (3° C) or less, place
capacity control switch in AUTO. position, return steam
pressure to normal and allow purge to establish the nor-
mal 2° F (1° C) or less absorber loss rate.
5. After evacuation, check the noncondensable accumula-
tion rate to determine machine tightness (see Mainte-
nance Procedures, Noncondensable Accumulation Rate
section, page 31).
Start-Up After Below-Freezing Conditions —
Refill all water circuits if previously drained. Then follow
procedure for Start-Up After Extended Shutdown.
Remove solution from the refrigerant circuit by following
the procedure, Removing Lithium Bromide from Refriger-
ant, page 35.
Machine Shutdown — Normal Conditions
1. Depress the Stop button momentarily. Machine goes through
automatic dilution for about 15 minutes and shuts down.
2. Close the main steam valve and stop system pumps. Leave
machine in this condition until the next start-up.
Machine Shutdown — Below Freezing

Conditions

1. Depress the Stop button momentarily. Wait until auto-
matic dilution is complete (about 15 minutes) and all ma-
chine pumps stop.
2. Close the main steam valve and stop system pumps.
3. Completely drain all tube bundles and flush all tubes with
an antifreeze chemical such as glycol.
4. a. The refrigerant circuit requires special treatment. Fill
a hose with water (to avoid letting air into the ma-
chine), and connect it between the solution pump and
refrigerant pump service valves.
b. Start the machine and open both service valves. Keep
the steam valve closed. If the machine has a refrig-
erant pump with above atmospheric discharge pres-
sure, it must be stopped for this procedure.
c. Allow solution pump to run for 10 minutes. This will
transfer lithium bromide solution into the refrigerant,
lowering the refrigerant freezing point. Close the serv-
ice valves and remove the hose.
d. Leave the machine running with all machine pumps
operating for about one minute to be sure lithium
bromide has been mixed throughout the refrigerant
circuit.
e. Depress the Stop button.
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