Carrier Weathermaster 48P2030-100, Controls, Start-Up, Operation, Service, And Troubleshooting

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CONDENSATE DRAIN
Check and clean each year at start of cooling season. In winter,
keep drains and traps dry.
FILTERS
Clean or replace at start of each heating and cooling season, or
more often if operating conditions require. Refer to Installation
Instructions for type and size.
1. Remove economizer outdoor-air filters from the hoods by
removing the filter retainers.
2. Clean filters with steam or hot water and mild detergent.
3. Reinstall filters in hoods after cleaning. Never replace
cleanable filters with throwaway filters.
OUTDOOR-AIR INLET SCREENS
Clean screens with steam or hot water and a mild detergent. Do
not use disposable filters in place of screens.
Lubrication
FAN SHAFT BEARINGS
Lubricate fan shaft bearings at least once a year with suitable
bearing grease. Extended grease lines are provided on pulley
side of blower. Typical lubricants are given below:
*Preferred lubricant because it contains rust and oxidation inhibitors.
FAN MOTOR BEARINGS
The condenser-fan and evaporator-fan motors have sealed
bearings, so no field lubrication is required.
DOOR HINGES
All door hinges should be lubricated at least once a year.
Refrigerant Feed Components
Each refrigerant circuit (2 per unit) has all the necessary refrig-
erant controls.
Thermostatic Expansion Valve (TXV)
On sizes 030 and 035, each circuit has one TXV. On sizes 040-
100, each circuit has 2 TXVs on which superheat may be
adjusted if necessary. Adjustment is not normally required or
recommended.
The TXV is set to maintain 10°F to 13°F superheat leaving the
evaporator coil. It controls the flow of refrigerant to the evapo-
rator coils.
Refrigeration Circuits
LEAK TESTING
Units are shipped with a full operating charge of R-410A (see
unit nameplate). If there is no pressure in the system, introduce
enough nitrogen to search for the leak. Repair the leak using
good refrigeration practices. After leaks are repaired, system
must be evacuated and dehydrated using methods described in
GTAC II, Module 4, System Dehydration.
REFRIGERANT CHARGE
Amount of refrigerant charge is listed on unit nameplate. Refer to
Carrier GTAC II; Module 5; Charging, Recovery, Recycling, and
Reclamation section for charging methods and procedures.
Unit panels must be in place when unit is operating during
charging procedure.
NOTE: Do not use recycled refrigerant as it may contain
contaminants.
NO CHARGE
Use standard evacuating techniques. After evacuating system,
weigh in the specified amount of refrigerant from the unit
nameplate.
LOW CHARGE COOLING
Due to the compact, all aluminum design, microchannel heat
exchangers will reduce refrigerant charge and overall operating
weight. As a result, charging procedures for MCHX units re-
quire more accurate measurement techniques. Charge should
be added in small increments. Using cooling charging charts
provided (Fig. 55-92), add or remove refrigerant until condi-
tions of the chart are met. As conditions get close to the point
on the chart, add or remove charge in
1
/
4
lb increments until
complete. Ensure that all fans are on and all compressors are
running when using charging charts.
CAUTION
UNIT DAMAGE HAZARD
Excessive water pressure will fracture the braze between air
centers and refrigerant tubes.
MANUFACTURER LUBRICANT
Texaco Regal AFB-2*
Mobil Mobilplex EP No. 1
Sunoco Prestige 42
Texaco Multifak 2