506762-01
Page 9 of 24
Issue 1143
To install an expansion valve (see Figure 9):
1.
Separate the distributor assembly and remove the piston
orifice and used teflon seal. Insert nozzle end of the
expansion valve along with a new teflon seal into the
distributor and tighten to 20 – 30 ft. lbs. Use backup wrench
on all wrench flats.
Overtightening will crush the teflon
seal and may cause a leak.
2.
Attach liquid line portion of distributor assembly along
with new teflon seal to the inlet of the expansion valve.
Tighten to 20 – 30 ft. lbs. Use backup wrench on all
wrench flats.
Overtightening will crush the teflon seal
and may cause a leak.
3.
Connect the external equalizer line to the equalizer port
on the suction line and tighten to 8 ft. lbs.
4.
Strap the superheat sensing bulb to the suction header.
If installing an expansion valve on an indoor coil that
previously used a fixed orifice, be sure to remove the existing
fixed orifice. Failure to remove a fixed orifice when installing
an expansion valve to the indoor coil will result in improper
operation and damage to the system.
Manifold Guage Set
Manifold gauge sets used with systems charged with R410A
refrigerant must be capable of handling the higher system
operating pressures. The gauges should be rated for use
with pressures 0 – 800 on the high side and a low side of
30" vacuum to 250 psi with dampened speed to 500 psi.
Gauge hoses must be rated for use at up to 800 psi of
pressure with a 4000 psi burst rating.
Liquid and SuctionLine Service Valves
The liquid line and suction line service valves and service
ports are used for leak testing, evacuating, charging, and
checking charge.
appropriately sized to be matched with the unit. If necessary,
replace the existing indoor unit fixed orifice with the orifice
supplied with the unit. Place the supplied fixed orifice sticker
on the indoor cabinet after installation.
Figure 9 shows how to install the replacement fixed orifice.
Do not twist cap tubes when loosening the seal nut from the
orifice housing. Use wrench to back up the distributor.
Expansion Valve Systems
Expansion valves equipped with Chatleff-type fittings are
available from the manufacturer. See Table 3 for proper
TXV size for each unit.
Metering Device Installation
Figure 9
If necessary, remove R22 flow control device (fixed
orifice/thermal expansion valve) from existing line
set before installing R-410A approved orifice or
expansion valve.
Each valve is equipped with a service port which has a factory-
installed Schrader valve. A service port cap protects the
Schrader valve from contamination and serves as the primary
leak seal.
To Access the Schrader Port:
1.
Remove the service port cap with an adjustable wrench.
2.
Connect gauge to the service port.
3.
When testing is completed, replace service port cap.
Tighten finger tight, then an additional 1/6 turn.
