ASPT Service Manual

Table Of Contents
SERVICING
95
Underfeeding
Underfeeding by the expansion valve results in low system
capacity and low suction pressures.
If these symptoms are observed:
1. Check for a restricted liquid line or drier. A restriction will
be indicated by a temperature drop across the drier.
2. Check the operation of the power element of the valve as
described in Checking Expansion Valve Operation.


1. Purge gauge lines. Connect service gauge manifold to
base-valve service ports. Run system at least 10 minutes
to allow pressure to stabilize.
2. Temporarily install a thermometer 4-6” from the compressor
on the suction line. Ensure the thermometer makes
adequate contact and is insulated for best possible
readings. Use vapor temperature to determine superheat.
3. Refer to the superheat table provided for proper system
superheat. Add charge to lower superheat or recover
charge to raise superheat.
4. Disconnect manifold set, installation is complete.
Superheat Formula = Suct. Line Temp. - Sat. Suct.
Temp.
Model Cur. Rev Piston Prev. Rev Piston
G/VSZ140181 LA .032 KF .039
G/VSZ140241 LA .047 KH .047
G/VSZ140301 KG .052 KF .052
G/VSZ140361 KE .059 LA .059
G/VSZ140421 KE .061 KD .061
G/VSZ140481 KF .065 KE .065
G/VSZ140491 KE .065 KD .065
G/VSZ140601 KE .065 KD .065
Model Cur. Rev Piston Prev. Rev Piston
ASZ140181 KE .039 KD .039
ASZ140241 KD .047 KC .047
ASZ140301 KD .052 KC .052
ASZ140361 KD .059 KC .059
ASZ140381 AC .059 n/a .059
ASZ140421 KD .061 KC .061
ASZ140481 KD .065 KC .065
ASZ140491 KD .065 KC .065
ASZ140601 KC .065 KB .065
Model Cur. Rev Piston Prev. Rev Piston
ANZ140181 AE .039 AD .039
ANZ140241 AD .047 AA .047
ANZ140301 AE .052 AD .052
ANZ140361 AD .059 AC .059
ANZ140421 AD .061 AC .061
ANZ140481 AD .065 AC .065
ANZ140491 AD .065 AC .065
ANZ140601 AC .065 AB .065
Pistons Used in Outdoor Heat Pump Coils
Goodman 14 SEER Heat Pumps
Amana 14 SEER Heat Pumps
Amana 14 SEER Heat Pumps
CAUTION
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



1. Run system at least 10 minutes to allow pressure to
stabilize.
2. For best results, temporarily install a thermometer on the
liquid line at the liquid line service valve and 4-6” from the
compressor on the suction line. Ensure the thermometer
makes adequate contact and is insulated for best possible
readings. Use liquid line temperature to determine sub-
cooling and vapor temperature to determine superheat.