Trane A5HP4 Installation And Operation Manual page 16

STEP 3 - Record System Information for reference.
Record system pressures and temperatures after
charging is complete.
Outdoor model number = _________________
Measured Outdoor Ambient = __________ º F
Measured Indoor Ambient = __________ º F
Measured Liquid Line Temp = __________ º F
STEP 4 - Complete the 'Total System Charge' charge rating label below and label located on the outside of the
unit with a permanent marker.
a. Charge added at Factory = ___________ lb/oz
b. Charge added at install = ___________ lb/oz
c. Total System Charge (a + b) = ___________ lb/oz
14.3 Subcooling Charging Below 55º F Outdoor Temp. (In Heating Only)
The Subcooling Charging method in cooling is not recommended below 55º F outdoor temperature.
The recommended method of charging at outdoor temperatures below 55º F is weighing in the charge. Return
when weather conditions permit charge verification through subcooling.
STEP 1 - Determine additional charge.
Note: The nameplate charge value represents the amount of refrigerant shipped in the outdoor unit and is com-
patible with 10 feet of AHRI rated refrigerant lines and the smallest AHRI rated coil.
Using the method below, find the charge associated with the additional length of tubing above 10 ft. and record it
below.
Weigh-In Method can be used for the initial installation, or anytime a system charge is being replaced. Weigh-In
Method can also be used when power is not available to the equipment site or operating conditions (indoor/out-
door temperatures) are not in range to verify with the subcooling charging method.
Calculating Charge Using the Weigh-In Method
1. Measure in feet the distance between the out-
door unit and the indoor unit. (Include the entire
length of the line from the service valve to the
IDU.) Subtract 10 ft from this entire length and
record on line 1.
2. Enter the charge multiplier (0.6 oz/ft). Each lin-
ear foot of interconnecting tubing requires the ad-
dition of 0.6 oz of refrigerant.
3. Multiply the total length of refrigerant tubing (Line
1) times the value on Step 2. Record the result
on Line 3 of the Worksheet.
4. This is the amount of refrigerant to weigh-in prior
to opening the service valves.
16
Measured Suction Line Temp = __________ º F
Liquid Gage Pressure = __________ PSIG
Suction Gage Pressure = __________ PSIG
1. Total Line length (ft) – 10 ft ______________
2. Charge multiplier
3. Step 1 x Step 2
4. Refrigerant (oz)
x ___0.6 oz _____
= _____________
= _____________
88-A5HP4001-1A-EN