Trane 4PXFH001BC3HHA - TXV Bulb Horizontal Mounting; TXV Bulb Mounting Criteria; TXV Bulb Vertical Mounting

18-AD40D1-1B-EN 5
Installer’s Guide
CAUTION
!
TXV sensing bulb is sensitive to heat. Do not
assemble to suction/vapor line until after field
brazing is complete and line is cool to touch.
I. TXV BULB HORIZONTAL MOUNTING
The orientation and location of the TXV bulb has a major
inuence on the system performance.
It is recommended that the TXV bulb be installed parallel
to the ground (on a horizontal plane). The bulb position
should be at 2 o-clock or 10 o-clock. See Figure 4 for
recommended position of TXV bulb in the horizontal
plane.
J. TXV BULB VERTICAL MOUNTING
While it is recommended that the TXV sensing bulb
is mounted in the horizontal plane, some installation
congurations may require that the sensing bulb be
mounted vertically. In this instance, place the bulb such
that the capillary tubes are directed upwards as shown in
Figure 5.
The TXV sensing bulb should be mounted away from any
bends on a clean smooth section of suction/vapor line,
using the metal clamp provided. In order to obtain a good
temperature reading and correct superheat control, the
TXV sensing bulb must conform to the following criteria:
1. The sensing bulb must be in direct and continuous
contact with the suction line.
2. The sensing bulb should be mounted horizontally on
the suction line.
3. The sensing bulb should be mounted at the 2 o'clock
or 10 o'clock position on the circumference of the
suction line.
4. The sensing bulb must be insulated from outside air.
A properly mounted sensing bulb will prevent false
readings caused by liquid refrigerant that may have
formed inside the suction/vapor line. Insulation will
protect the sensing bulb from false readings due to
contact with warm air.
SENSING BULB
SUCTION LINE
Bulb position at
2 o’clock or
10 o’ clock
Refrigerant &
Oil Flow
Direct Capillary
Tube Upwards
Metal
Strap
Sensing Bulb location
on pipe wall opposite
to that being hit by
refrigerant and
oil leaving the
distributor tubes
Suction
Line
④
⑤
RECOMMENDED LOCATION FOR
VERTICAL TXV BULB MOUNT
RECOMMENDED LOCATION FOR
HORIZONTAL TXV BULB MOUNT