Adjusting Speed Tap For Id Blower Motor; Eem Motor; [Gpc/*Ph] Cfm Delivery And Adjustments; [Gpc/*Ph] Thermostat "Fan Only" Mode - Goodman M Series Installation Instructions Manual

Figure 13: Total External Static
2. Measure the static pressure of the supply duct
(Positive Pressure).
3. Add the two readings together
NOTE: Both readings may be taken simultaneously
and read directly on the manometer if so desired.
4. Consult proper table for quantity of air.
If the external static pressure exceeds the minimum or
maximum allowable statics, check for closed dampers, dirty
filter, undersized or poorly laid out ductwork.
ADJUSTING SPEED TAP FOR INDOOR
BLOWER MOTOR

EEM Motor

The blower motor speed for the EEM motor is controlled by
three 24V low voltage leads: green, yellow, and white. The
green lead sets the speed for fan-only mode. The yellow
lead sets the speed for cooling and heat pump heating
mode (if applicable).
EEM Motor Speed Adjustment
The white lead sets the speed for electric heat mode
(emergency heat and second stage heat, if applicable).
The leads are factory connected as follows: Green to T1,
Yellow to T2, and White to T3. T1 is the low speed setting
and is dedicated to fan-only mode. T2 is medium speed
cooling and T3 is medium speed heating. T4 is high speed
cooling and T5 is high speed heating. To adjust the blower
speed, move the yellow and/or white wires to T4 and T5.
NOTE: If more than one lead is energized at the
same time, the motor will use the higher speed
setting.
See appendix for Blower Performance Data tables.
[GPC/*PH]M3 CFM Delivery and Adjustments
See Appendix for CFM Output, Adjustments, and DIP
switch settings.
[GPC/*PH]M3 Thermostat "Fan Only" Mode
During Fan Only Operations, the CFM output is 50% of the
high stage cooling setting.

SUPERHEAT AND SUBCOOLING

Checking Subcooling

NOTE: Units with a TXV should be charged to
Subcooling only.
EXAMPLE:
a. Liquid Line Pressure = 417 PSI
b. Corresponding Temp. = 120°F
c. Thermometer on Liquid line = 109°F.
To obtain the amount of subcooling, subtract 109°F
from 120°F. The difference is 11° subcooling. See the
specification sheet or technical information manual for the
design subcooling range for your unit.
SUBCOOLING FORMULA = SATURATED LIQUID LINE
TEMPERATURE - LIQUID LINE TEMPERATURE

Checking Superheat

EXAMPLE:
a. Suction Pressure = 143 PSI
b. Corresponding Temp. = 50°F
c. Thermometer on Suction Line = 59°F
To obtain the degrees temperature of superheat, subtract
50.0 from 59.0°F. The difference is 9° Superheat. The 9°
Superheat would fall in the ± range of allowable superheat.
SUPERHEAT = SUCTION LINE TEMP - SAT. SUCTION
TEMP.

Superheat Adjustment

NOTE: Superheat adjustments should not be made
until indoor ambient conditions have stabilized.
This could take up to 24 hours depending on
indoor temperature and humidity. Before checking
superheat, run the unit in cooling for 10-15
minutes or until refrigerant pressures stabilize.
Use the following guidelines and methods
to check unit operation and ensure that the
refrigerant charge is within limits.
For TXV systems, to adjust superheat, unscrew the cover
from the expansion valve, locate the adjustment screw,
and turn it clockwise (in) to increase superheat or counter-
clockwise (out) to decrease superheat. It is recommended
to make small adjustments at a time, 1/8-1/4 turn increments.
Replace adjustment cap. Wait a minimum of 10 minutes
between adjustments to allow time for the TXV and pres-
sures to stabilize.

Refrigerant Charge Check

NOTE: For optimal performance, follow charging
instructions below.
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