Operating Service Valves; General - Lennox XC25-024-230-01 Installation And Service Procedure

WARNING
Electric Shock Hazard. Can cause injury
or death. Unit must be grounded in
accordance with national and local
codes.
Line voltage is present at all components
when unit is not in operation on units with
single‐pole contactors. Disconnect all
remote electric power supplies before
opening access panel. Unit may have
multiple power supplies.

General

These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
who have jurisdiction before installation.
The XC25 is a high-efficiency residential split-system air
conditioner, which features a variable-capacity scroll com­
pressor and uses HFC-410A refrigerant. Units are
available in 2, 3, 4 and 5-ton sizes. The series is designed
for use with an expansion valve (approved for use with
HFC-410A) in the indoor unit only.
USING MANIFOLD GAUGE SET
When checking the system charge, only use a manifold
gauge set that features low loss anti-blow back fittings.
Manifold gauge set used with HFC-410A refrigerant sys­
tems must be capable of handling higher system operating
pressures. The gauges should be rated for use with pres­
sures of 0 - 800 psig on the high side and a low side of 30"
vacuum to 250 psig, with dampened speed to 500 psi.
Gauge hoses must be rated for use at or up to 800 psig of
pressure with a 4000 psig burst rating.
Table 1. Torque Requirements
Parts Recommended Torque
Service valve cap 8 ft.- lb.
Sheet metal screws 16 in.- lb.
Machine screws #10 28 in.- lb.
Compressor bolts 90 in.- lb.
Gauge port seal cap 8 ft.- lb.
TORQUE REQUIREMENTS
When servicing or repairing HVAC components, ensure
the fasteners are appropriately tightened. Table 1 lists
torque values for fasteners.

Operating Service Valves

The liquid and vapor line service valves are used for re­
moving refrigerant, flushing, leak testing, evacuating,
checking charge and charging.
Each valve is equipped with a service port which has a fac­
tory-installed valve stem. Figure 3 provides information on
how to access and operating both angle and ball service
valves.
Only use hex wrenches of sufficient hardness (50Rc -
Rockwell Harness Scale minimum). Fully insert the
wrench into the valve stem recess.
Service valve stems are factory-torqued (from 9 ft-lbs for
small valves, to 25 ft-lbs for large valves) to prevent
refrigerant loss during shipping and handling. Using a
hex wrench rated at less than 50Rc risks rounding or
breaking off the wrench, or stripping the valve stem
recess.
See the Lennox Service and Application Notes #C-08-1
for further details and information.
The State of California has determined that this product
may contain or produce a chemical or chemicals, in very
low doses, which may cause serious illness or death. It
may also cause cancer, birth defects, or reproductive
harm.
11 NM
2 NM
3 NM
To prevent stripping of the various caps used, the
10 NM
appropriately sized wrench should be used and fitted
snugly over the cap before tightening.
11 NM
7
IMPORTANT
WARNING
IMPORTANT
XC25