background image

Page 14

CHECKING AND ADDING SYSTEM
REFRIGERANT

The 13ACX unit is factory-charged with enough HFC-410A
refrigerant to accommodate a 15-foot length of refrigerant
piping. Charge should be checked and adjusted using the
tables provided on the charging procedure sticker located on
the unit access panel. Detailed information is provided in the
13ACX Installation and Service Procedures manual
(Corp0625-L5), which is available on DaveNet.

Homeowners Information

CAUTION

Before attempting to perform any service or mainte­
nance, turn the electrical power to unit OFF at discon­
nect switch.

Cleaning of the outdoor unit's coil should be performed by a
licensed professional service technician (or equivalent).
Contact your dealer and set up a schedule (preferably twice
a year, but at least once a year) to inspect and service your
outdoor unit. The following maintenance may be performed
by the homeowner.

Outdoor Coil

The outdoor unit must be properly maintained to ensure its
proper operation.

S

Please contact your dealer to schedule proper inspection
and maintenance for your equipment.

S

Make sure no obstructions restrict airflow to the outdoor
unit.

S

Grass clippings, leaves, or shrubs crowding the unit can
cause the unit to work harder and use more energy.

S

Keep shrubbery trimmed away from the unit and
periodically check for debris which collects around the
unit.

S

Keep snow level below the louvered panels to ensure
proper performance.

IMPORTANT !

Sprinklers and soaker hoses should not be installed
where they could cause prolonged exposure to the
outdoor unit by treated water. Prolonged exposure of
the unit to treated water (i.e., sprinkler systems, soak­
ers, waste water, etc.) will corrode the surface of steel
and aluminum parts, diminish performance and af­
fect longevity of the unit.

Routine Maintenance

In order to ensure peak performance, your system must be
properly maintained. Clogged filters and blocked airflow
prevent your unit from operating at its most efficient level.

NOTE 

 The filter and all access panels must be in place

any time the unit is in operation. If you are unsure about the
filter required for your system, call your Lennox dealer for
assistance.

1. Ask your Lennox dealer to show you where your indoor

unit's filter is located. It will be either at the indoor unit
(installed internal or external to the cabinet) or behind a
return air grille in the wall or ceiling. Check the filter
monthly and clean or replace it as needed.

2. Disposable filters should be replaced with a filter of the

same type and size.

3. The indoor evaporator coil is equipped with a drain pan

to collect condensate formed as your system removes
humidity from the inside air. Have your dealer show you
the location of the drain line and how to check for
obstructions. (This would also apply to an auxiliary
drain, if installed.)

Thermostat Operation

See the ComfortSense

®

 7000 thermostat homeowner

manual for instructions on how to operate your thermostat.

Preservice Check

If your system fails to operate, check the following before
calling for service:

S

Verify room thermostat settings are correct.

S

Verify that all electrical disconnect switches are ON.

S

Check for any blown fuses or tripped circuit breakers.

S

Verify unit access panels are in place.

S

Verify air filter is clean.

S

If service is needed, locate and write down the unit
model number and have it handy before calling.

Summary of Contents for Merit 13ACX-018-230

Page 1: ... Units AIR CONDITIONER 506945 01 5 2013 Supersedes 7 2012 WARNING Improper installation adjustment alteration service or maintenance can cause personal injury loss of life or damage to property Installation and service must be performed by a licensed professional installer or equivalent or a service agency CAUTION Before attempting to perform any service or maintenance turn the electrical power to...

Page 2: ...ICE Roof Damage This system contains both refrigerant and oil Some rubber roofing material may absorb oil causing the rubber to degrade Failure to follow this notice could result in damage to roof surface IMPORTANT This model is designed for use in check expansion valve systems only An indoor expansion valve ap proved for use with HFC 410A refrigerant must be or dered separately and installed prio...

Page 3: ...THE LIQUID LINE TO THE VAPOR LINE FLOOR JOIST OR ROOF RAFTER REFRIGERANT LINE SET INSTALLING HORIZONTAL RUNS NOTE Similar installation practices should be used if line set is to be installed on exterior of outside wall PVC PIPE FIBERGLASS INSULATION CAULK OUTSIDE WALL VAPOR LINE WRAPPED WITH ARMAFLEX LIQUID LINE OUTSIDE WALL LIQUID LINE VAPOR LINE WOOD BLOCK BETWEEN STUDS STRAP WOOD BLOCK STRAP SL...

Page 4: ...t that the refrigerant system be kept closed as much as possible DO NOT remove line set caps or service valve stub caps until you are ready to make connections IMPORTANT Some scroll compressors have an internal vacuum protector that will unload scrolls when suction pres sure goes below 20 psig A hissing sound will be heard when the compressor is running unloaded Protector will reset when low press...

Page 5: ... Teflon rings H Use a field provided fitting to temporarily reconnect the liquid line to the indoor unit s liquid line orifice housing LOW HIGH EXISTING INDOOR UNIT GAUGE MANIFOLD CYLINDER CONTAINING CLEAN HCFC 22 TO BE USED FOR FLUSHING Positioned to deliver liquid refrigerant LIQUID LINE SERVICE VALVE INLET DISCHARGE TANK RETURN CLOSED OPENED RECOVERY CYLINDER RECOVERY MACHINE NEW OUTDOOR UNIT V...

Page 6: ...nts and debur the ends The pipe must remain round Do not crimp end of the line Remove service cap and core from both the suction vapor and liquid line service ports 1 2 ANGLE TYPE SERVICE VALVE SERVICE PORT CORE SERVICE PORT CAP SERVICE PORT CORE SERVICE PORT CAP CUT AND DEBUR LINE SET SIZE MATCHES SERVICE VALVE CONNECTION COPPER TUBE STUB SERVICE VALVE CONNECTION REFRIGERANT LINE DO NOT CRIMP SER...

Page 7: ...ed cloths WHEN BRAZING LINE SET TO SERVICE VALVES POINT FLAME AWAY FROM SERVICE VALVE PREPARATION FOR NEXT STEP 7 WRAP SERVICE VALVES To help protect service valve seals during brazing wrap water saturated cloths around service valve bodies and copper tube stubs Use additionalwater saturated cloths underneath the valve body to protect the base paint 4 FLOW NITROGEN Flow regulated nitrogen at 1 to ...

Page 8: ...6 7 8 9 10 11 12 1 2 Turn SENSING BULB INSTALLATION EQUALIZER LINE INSTALLATION 1 2 3 4 5 6 7 8 9 10 11 12 1 8 Turn A Remove and discard either the flare seal cap or flare nut with copper flare seal bonnet from the equalizer line port on the vapor line as illustrated in the figure below B Remove the field provided fitting that temporarily reconnected the liquid line to the indoor unit s distributo...

Page 9: ... indoor unit E After a few minutes open one of the service valve ports and verify that the refrigerant added to the system earlier is measurable with a leak detector F After leak testing disconnect gauges from service ports After the line set has been connected to the indoor and outdoor units check the line set connections and indoor unit for leaks Use the following procedure to test for leaks A C...

Page 10: ...utting off the vacuum pump and closing the manifold gauge valves F When the absolute pressure requirement above has been met disconnect the manifold hose from the vacuum pump and connect it to a cylinder of HFC 410A positioned to deliver liquid refrigerant Open the manifold gauge valve 1 to 2 psig in order to release the vacuum in the line set and indoor unit G Perform the following A Connect low ...

Page 11: ... damage as a result of slugging CAUTION ELECTROSTATIC DISCHARGE ESD Precautions and Procedures Electrostatic discharge can affect electronic components Take care during unit installation and service to protect the unit s electroniccontrols Precautionswill help to avoid control exposure to electrostatic dischargebyputtingthe unit the control and the technician at the same electrostatic potential To...

Page 12: ...binding 2 Inspect all factory and field installed wiring for loose connections 3 After evacuation is complete open the liquid line and suction line service valve stems to release the refrigerant charge contained in outdoor unit into the system 4 Replace the stem caps and tighten to the value listed in table 3 5 Check voltage supply at the disconnect switch The voltage must be within the range list...

Page 13: ...nsion 3 16 for liquid line valve sizes and 5 16 for vapor line valve sizes to back the stem out counterclockwise as far as it will go Operating Ball Type Service Valve 1 Remove stem cap with an appropriately sized wrench 2 Use an appropriately sized wrenched to open To open valve rotate stem counterclockwise 90 To close rotate stem clockwise 90 1 2 3 4 5 6 7 8 9 10 11 12 1 12 TURN To Access Servic...

Page 14: ...nged exposure of the unit to treated water i e sprinkler systems soak ers waste water etc will corrode the surface of steel and aluminum parts diminish performance and af fect longevity of the unit Routine Maintenance In order to ensure peak performance your system must be properly maintained Clogged filters and blocked airflow prevent your unit from operating at its most efficient level NOTE The ...

Page 15: ...ure Supply Air Temperature Ambient Temperature Return Air Temperature System Refrigerant Charge Refer to manufacturer s information on unit or installation instructions for required subcooling and approach temperatures Subcooling A B SUBCOOLING Saturated Condensing Temperature A minus Liquid Line Temperature B Approach A B APPROACH Liquid Line Temperature A minus Outdoor Air Temperature B Indoor C...

Reviews: