Carrier Infinity 15 SEER 50XT-A Скачать руководство пользователя

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Step 9 — Pressure Switches

Pressure switches are protective devices integrated into the control
circuit (low voltage). They shut off compressor if abnormally high

or low pressures are present in the refrigeration circuit. These

pressure switches are specifically designed to operate with Puron
(R--410A) systems. R--22 pressure switches must not be used as

replacements for the Puron (R--410A) system.
Loss--of--Charge (Low Pressure) Switch
This switch is located on the liquid line and protects against low
suction pressures caused by such events as loss of charge, low

airflow across indoor coil, dirty filters, etc. It opens if the system

pressure drops to about 20 psig. If system pressure is above this,
switch should be closed.
High--Pressure Switches (HPS & HPS2)
The high--pressure switches are located on the discharge line and

protects against excessive condenser coil pressure. HPS opens at

670 psig shutting down the compressor, while HPS2 opens at 565,
limiting the compressor to low--stage operation only.
High pressure may be caused by a dirty outdoor coil, failed fan
motor, or outdoor air recirculation.
To check switches:

1. Turn off all power to unit.
2. Disconnect leads on switch.
3. Apply ohm meter leads across switch. You should have

continuity on a good switch.

NOTE

Because these switches are attached to refrigeration

system under pressure, it is not advisable to remove this device for
troubleshooting unless you are reasonably certain that a problem
exists. If switch must be removed, remove and recover all system
charge so that pressure gauges read 0 psi. Never open system
without breaking vacuum with dry nitrogen.

Step 10 — Copeland Scroll Compressor (Puron

Refrigerant)

The compressor used in this product is specifically designed to

operate with Puron (R--410A) refrigerant and cannot be

interchanged.

The compressor is an electrical (as well as mechanical) device.

Exercise extreme caution when working near compressors. Power
should be shut off, if possible, for most troubleshooting techniques.

Refrigerants present additional safety hazards.

EXPLOSION, FIRE HAZARD

Failure to follow this warning could result in personal

injury or death and/or property damage.
Wear safety glasses and gloves when handling refrigerants.

Keep torches and other ignition sources away from

refrigerants and oils.

WARNING

The scroll compressor pumps refrigerant throughout the system by

the interaction of a stationary and an orbiting scroll. The scroll
compressor has no dynamic suction or discharge valves, and it is

more tolerant of stresses caused by debris, liquid slugging, and
flooded starts. The compressor is equipped with noise reducing

shutdown device and an internal pressure--relief port. The noise

reducing shutdown device prevents the scroll from turning
backwards and replaces the need for a cycle protector. The

pressure--relief port is a safety device, designed to protect against
extreme high pressure. The relief port has an operating range

between 550 and 625 psi differential pressure.

The Copeland scroll compressor uses Mobil 3MA POE oil.

This is the only oil allowed for oil recharge.

Step 11 — Refrigerant System

This step covers the refrigerant system of the 50XT--A, including
the compressor oil needed, servicing systems on roofs containing

synthetic materials, the filter drier, and refrigerant charging.
REFRIGERANT

UNIT

OPERATION,

SAFETY

AND

ENVIRONMENTAL HAZARD

Failure to follow this warning could result in personal

injury or equipment damage.
This system uses Puron (R--410A) refrigerant which has

higher operating pressures than R--22 and other refrigerants.

No other refrigerant may be used in this system. Gauge set,

hoses, and recovery system must be designed to handle

Puron. If you are unsure, consult the equipment

manufacturer.

WARNING

COMPRESSOR OIL
The Copeland scroll compressor uses 3MAF POE oil. If additional

oil is needed, use Uniqema RL32--3MAF. If this oil is not

available, use Copeland Ultra 32 CC or Mobil Arctic EAL22 CC.
This oil is extremely hygroscopic, meaning it absorbs water

readily. POE oils can absorb 15 times as much water as other oils
designed to HCFC and CFC refrigerants. Take all necessary

precautions to avoild exposure of the oil to the atmosphere.
SERVICING SYSTEMS ON ROOFS WITH SYNTHETIC
MATERIALS
POE (polyolester) compressor lubricants are known to cause long
term damage to some synthetic roofing materials.
Exposure, even if immediately cleaned up, may cause
embrittlement (leading to cracking) to occur in one year or more.

When performing any service that may risk exposure of

compressor oil to the roof, take appropriate precautions to protect
roofing. Procedures which risk oil leakage include, but are not

limited to, compressor replacement, repairing refrigerant leaks, and
replacing refrigerant components such as filter drier, pressure

switch, metering device, coil, accumulator, or reversing valve.
Synthetic Roof Precautionary Procedure

1. Cover extended roof working area with an impermeable

polyethylene (plastic) drip cloth or tarp. Cover an
approximate 10x10 ft (3x3 m) area.

2. Cover area in front of the unit service panel with a terry

cloth shop towel to absorb lubricant spills and prevent
run--offs, and protect drop cloth from tears caused by tools

or components.

3. Place terry cloth shop towel inside unit immediately under

component(s) to be serviced and prevent lubricant run--offs

through the louvered openings in the unit base.