Comfort PRL-series Bedienungsanleitung PDF herunterladen

START-UP AND PERFORMANCE

Even though the unit is factory charged with Refrigerant-410A,

the charge must be checked to the charge table attached to the

service panel and adjusted, if required.

At initial start-up or after extended shutdown periods, make sure

the heater is energized for at least 12 hours before the com-

pressor is started. (Disconnect switch on

and wall thermostat

off

START-UP – CHECKING AIRFLOW

The air distribution system has the greatest effect on airflow.

The duct system is totally controlled by the contractor. For this

reason, the contractor should use only industry-recognized

procedures. The correct air quantity is critical to air condition-

ing systems. Proper operation, efficiency, compressor life, and

humidity control depend on the correct balance between in-

door load and outdoor unit capacity. Excessive indoor airflow

increases the possibility of high humidity problems. Low in-

door airflow reduces total capacity and causes coil icing. Seri-

ous harm can be done to the compressor by low airflow, such

as that caused by refrigerant flooding. Heat pump systems re-

quire a specified airflow. Each ton of cooling requires between

375 and 450 cubic feet of air per minute (CFM). See the man-

ufacturer’s spec sheet for rated airflow for the system being

installed. Duct design and construction should be carefully

done. System performance can be lowered dramatically

through bad planning or workmanship. Air supply diffusers

must be selected and located carefully. They must be sized

and positioned to deliver treated air along the perimeter of the

space. If they are too small for their intended airflow, they be-

come noisy. If they are not located properly, they cause drafts.

Return air grilles must be properly sized to carry air back to

the blower. If they are too small, they also cause noise. The

installers should balance the air distribution system to ensure

proper quiet airflow to all rooms in the home. This ensures a

comfortable living space.

These simple mathematical formulas can be used to deter-

mine the CFM in a residential or light commercial system.

Electric resistance heaters can use:

CFM =

volts x amps x 3.413

SHC x temp rise

Gas furnaces can use:

CFM =

Output Capacity in BTUH*

SHC x temp rise

*Refer to furnace data plate for furnace output capacity. SHC

= Sensible Heat Constant (see table below), an air velocity

meter or airflow hood can give a more accurate reading of the

system CFM. The measurement for temperature rise should

be performed at the indoor coil inlet and near the outlet, but

out of direct line of sight of the heater element or heat ex-

changer. For best results, measure air temperature at multiple

points and average the measurements to obtain coil inlet and

outlet temperatures.

EVACUATION AND LEAK TESTING

EVACUATION PROCEDURE

Evacuation is the most important part of the entire service

procedure. The life and efficiency of the equipment is depend-

ent upon the thoroughness exercised by the serviceman when

evacuating air and moisture from the system.

Air or nitrogen in the system causes high condensing temper-

atures and pressure, resulting in increased power input and

non-verifiable performance.

Moisture chemically reacts with the refrigerant and oil to form

corrosive hydrofluoric acid. This attacks motor windings and

parts, causing breakdown.

• After the system has been leak-checked and proven sealed,

connect the vacuum pump and evacuate system to 500 mi-

crons and hold 500 microns or less for at least 15 minutes.

The vacuum pump must be connected to both the high and

low sides of the system by connecting to the two pressure

ports. Use the largest size connections available since re-

strictive service connections may lead to false readings be-

cause of pressure drop through the fittings.

• After adequate evacuation, open both service valves by re-

moving both brass service valve caps with an adjustable

wrench. Insert a 3/16” [5 mm] or 5/16” [8 mm] hex wrench

into the stem and turn counterclockwise until the wrench

stops.

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Altitude

(feet)

SENSIBLE HEAT

CONSTANT

(SHC)

ALTITUDE

(FEET)

SENSIBLE HEAT

CONSTANT

(SHC)

Sea Level 1.08 6000 0.87

500 1.07 7000 0.84

1000 1.05 8000 0.81

2000 1.01 9000 0.78

3000 0.97 10000 0.75

4000 0.94 15000 0.61

5000 0.90 20000 0.50

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Inhaltsverzeichnis

Seite 1 - EVACUATION AND LEAK TESTING

START-UP AND PERFORMANCEEven though the unit is factory charged with Refrigerant-410A,the charge must be checked to the charge table attached to these

Seite 2 - CHECKING REFRIGERANT CHARGE

2 92-20522-89-00• At this time gauges must be connected to the access fittingon the liquid line (small) service valve and the common suc-tion port con

Seite 3 - FINAL CHARGE BY SUB-COOLING

92-20522-89-00 3IMPORTANT: Charging by weight is not always accuratesince the application can affect the optimum refrigerantcharge. Charging by wei

Seite 4 - FINISHING UP INSTALLATION

4 92-20522-89-00Step 5. Adjust Charge to obtain the specified sub-coolingvalue. If the measured sub-cool is below the listedrequirement for the given