Carrier 50TCQD17-D24 Service And Maintenance Instructions page 12

DIAPHRAGM
INLET
Replacing TXV
CAUTION
!
PERSONAL INJURY HAZARD
Failure to follow this caution can result in injury to
personnel and damage to components.
Always wear approved safety glasses, work gloves
and other recommended
Equipment (PPE) when working with refrigerants.
1. Recover refrigerant.
2. Remove TXV support clamp using a 5/l6-in. nut
driver.
3. Remove TXV using a backup wrench on connections
to prevent damage to tubing.
4. Remove equalizer tube from suction line of coil. Use
file or tubing cutter to cut brazed equalizer line
approximately 2 inches above suction tube.
5. Remove bulb from vapor tube inside cabinet.
6. Install the new TXV and avoid damaging the tubing
or the valve when attaching the TXV to the
distributor.
7. Attach equalizer tube to suction line. If coil has
mechanical connection, then use wrench and back up
wrench to attach. If coil has brazed connection, use
file or tubing cutters to remove mechanical flare nut
from equalizer line. Then use coupling to braze the
equalizer line to stub (previous equalizer line) in
suction line.
8. Attach TXV bulb in the same location as original (in
the sensing bulb indent), wrap bulb in protective
PUSHRODS
FEEDER TUBES
OUTLET
NEEDLE
VALVE
SPRING
DISTRIBUTOR
Fig. 19 - - Thermostatic Expansion Valve (TXV) Operation
Personal Protective
CAPILLARY TUBE
COIL
EXTERNAL EQUALIZER TUBE
insulation and secure using the supplied bulb clamp.
See Fig. 20.
9. Route equalizer tube through suction connection
opening (large hole) in fitting panel and install fitting
panel in place.
10. Sweat inlet of TXV marked "IN" to liquid line. Avoid
excessive heat which could damage valve.
CLAMP
TXV SENSING
BULB
SENSING BULB INSULATION REMOVED FOR CLARITY
Fig. 20 - - TXV Valve and Sensing Bulb
12
BULB
C12046
THERMAL EXPANSION
(TXV) VALVE
C12095