Carrier 38YCB(P), 38BYB, 38AYB ÐTypical TXV Installation, ÐPositioning of Sensing Bulb

NOTE: A thermostatic expansion valve (TXV) is required on all 38BYB units. Step 4 refers to the installation of the TXV.

Step 4ÐRemove Indoor AccuRater® Piston and Install

TXV

For proper unit operation and reliability, units must be installed with a field-supplied hard shut-off TXV. Do not install with evaporator coils having capillary tube metering devices or piston.

After removing existing AccuRater from indoor coil, install field-supplied bi-flow hard shut-off TXV kit. (See Fig. 7 and 8.)

COIL

SENSING

BULB

EQUALIZER

TUBE

THERMOSTATIC

EXPANSION

VALVE

A88382

Fig. 7ÐTypical TXV Installation

10 O'CLOCK

2 O'CLOCK

SENSING BULB

STRAP

SUCTION TUBE

8 O'CLOCK	4 O'CLOCK
7⁄8 IN. OD & SMALLER	LARGER THAN 7⁄8 IN. OD
	A81032

Fig. 8ÐPositioning of Sensing Bulb

For TXV kit part number and charging instruction, refer to TXV label in your unit. If the indoor unit (fan coil) comes factory equipped with a bi-flow hard shut-off TXV, no TXV change is required.

Install TXV kit to indoor coil as follows:

1.Install suction tube adapter.

2.Install liquid flare-to-sweat adapter.

3.Connect external equalizer tube to fitting on suction tube adapter.

4.Position sensing bulb on horizontal portion of suction tube adapter. Secure using supplied hardware.

5.Insulate bulb after installation. (See Fig. 8.)

6.Leak check all connections.

3