Carrier 19CB - Manual (Page 7)

With OIL PUMP button
depressed, alternately stop
and restart chilled water
and
condenser water
p u m p s . S A F E T Y
CIRCUIT and LOAD RECYCLE lights should
go out as each pump stops. (Continuous
operation of oil pump is unnecessary during
these checks.)
■ □ ■
ON
STOP
START OIL
PUMP
■ □ □ n
POWER SAFETY LOAD
CIRCUIT RECYCLE
PROGRAM
TIMER
9. Shut off water pumps. Re-
□ □ □
lease OIL PUMP button. ON START OIL
STOP PUMP
Press ON-STOP button
(light goes out). Replace
■ □
□ □
POWER SAFETY LOAO PROGRAM
tagged wire on terminal CIRCUIT RECYCLE TIMER
(L),
10. Press ON-STOP button ■ □ □
(light goes on). ON START OIL
STOP PUMP
■ ■ ■ □
POWER SAFETY LOAD PROGRAM
CIRCUIT RECYCLE TIMER
11. Press machine START
button (motor leads
disconnected).
Oil pump starts within 30
seconds.
Compressor motor start
contacts will close 30
seconds later. Starter will
transfer to its run condi­
tion 30 to 60 seconds
after starter is energized.
12. Open oil pump main dis­
connect. Starter must de­
energize. OIL PUMP light
will remain on for approx­
imately 5 minutes.
OIL PUMP light goes out.
■ ■ □
ON
STOP
START OIL
PUMP
■ ■ ■ ■
POWER SAFETY LOAD
CIRCUIT RECYCLE
PROGRAM
TIMER
■ ■ ■
ON
STOP
START OIL
PUMP
■ ■ ■ n
POWER SAFETY LOAD
CIRCUIT RECYCLE
PROGRAM
TIMER
■ □ ■
ON
STOP
START OIL
PUNIP
■ □ □ ■
POWER SAFETY LOAO
CIRCUIT RECYCLE
PROGRAM
TIMER
■ □ n
ON
STOP
START OIL
PUMP
■ □ □ ■
POWER SAFETY LOAO
CIRCUIT RECYCLE
PROGRAM
TIMER
■ □ □
ON
STOP
START OIL
PUMP
■ ■ ■ n
POWER SAFETY LOAO
CIRCUIT RECYCLE
PROGRAM
TIMER
13. Close oil pump dis­
connect. In approximately
10 minutes the program
timer will complete the
antirecycle portion of its
cycle
and machine is
ready to restart. (Total
recycle time —
15
minutes.)
14. Remove all power. Reconnect motor leads.
Restore power.
Purge — Place the purge operating valves (Fig. 1) in
“Normal-Automatic” position as indicated in Oper­
ation no. 1 on the purge valve operation plate.
Operate the purge momentarily by placing the
purge switch in “Manual” position; then place
purge switch in “Auto.” position.
Air Supply (Pneumatic Controls Only) — Check 25
psi air supply to pneumatic temperature controller
and pilot positioner.
START-UP
Before Starting Machine — Be sure that-
Power switch is on to circuit breakers, water pumps,
tower fan and control circuit.
Cooling tower water is at proper level.
Oil is visible in reservoir sight glass.
Oil reservoir temperature is 140 F or warmer.
Oil cooler plug cock is cracked open and any other
valve in the oil cooler line is fully open.
Refrigerant is at selected design level.
Valves in cooler and condenser water circuits are
open Do not permit water above 100 F to flow thru
cooler
Filter-drier shutoff valves (Item 24, Fig. 1) are open.
Air supply for pneumatic controls is adequate
COMPRESSOR ROTATION - Electronic Control:
Set capacity control switch on “Hold.”
Pneumatic Capacity Control: Turn off supply air
to chilled water thermostat and vane positioner.
Press machine ON-STOP and START buttons.
As soon as motor begins to turn, press machine
ON-STOP button. Check motor rotation thru sight
glass on motor end bell. Motor rotation must be
counterclockwise as viewed thru sight glass.
COMPRESSOR OPERATION — Press machine
ON-STOP and START buttons and let compressor
come up to speed. Press machine ON-STOP button
and listen for any unusual sounds from compressor
as it coasts to a stop.
The program timer prevents rapid recycling and
allows compressor restart 15 minutes after stop.
Checking Safety Control Settings
■While performiiig these checks, carefully moni­
tor cMlied -vt'ateT temperature to prevent
freeze>-up. Protection by safety controls cannot
be assumed until all settings have been con­
firmed as follows:
Open main disconnect (all power off to starter
and controls).
Electronic Control: Set capacity control switch on
“Hold.”
Pneumatic Control: Ensure that pilot positioner
operates as described in Setting Operating
Controls-Pneumatic. Then set percent load