GPG16M Installation Instructions

16
Gas Input (Natural Gas Only) Check
To measure the gas input use a gas meter and proceed as follows:
1. Turn off gas supply to all other appliances except the unit.
2. With the unit operating, time the smallest dial on the meter for one complete revolution. If this is a 2 cubic foot dial, divide
the seconds by 2; if it is a 1 cubic foot dial, use the seconds as is. This gives the seconds per cubic foot of gas being
delivered to the unit.
3. INPUT = GAS HTG VALUE x 3600 / SEC. PER CUBIC FOOT
Example: Natural gas with a heating value of 1000 BTU per cubic foot and 36 seconds per cubic foot as determined by Step 2, then:
Input = 1000 x 3600 / 36 = 100,000 BTU per Hour. NOTE: BTU content of the gas should be obtained from the gas supplier. This
measured input must not be greater than shown on the unit rating plate.
4. Relight all other appliances turned off in step 1. Be sure all pilot burners are operating.
Main Burner Flame Check
Flames should be stable, soft and blue (dust may cause orange tips but they must not be yellow) and extending directly outward from
the burner without curling, floating or lifting off.
Temperature Rise Check
Check the temperature rise through the unit by placing thermometers in supply and return air registers as close to the unit as possible.
Thermometers must not be able to sample temperature directly from the unit heat exchangers, or false readings could be obtained.
1. All registers must be open; all duct dampers must be in their final (fully or partially open) position and the unit operated for 15
minutes before taking readings.
2. The temperature rise must be within the range specified on the rating plate.
NOTE: Air temperature rise is the temperature difference between supply and return air.
With a properly designed system, the proper amount of temperature rise will normally be obtained when the unit is operated at rated
input with the recommended blower speed.
If the correct amount of temperature rise is not obtained, it may be necessary to change the blower speed. A higher blower speed will
lower the temperature rise. A slower blower speed will increase the temperature rise.
NOTE: Blower speed MUST be set to give the correct air temperature rise through the unit as marked on the rating plate.
External Static Pressure Check
The total external static pressure must be checked on this unit to determine if the airflow is proper.
Blower Speed Adjustments
Blower speeds are changed at the indoor blower. The ignition control
board has four blower speeds: LOW HEAT, HI HEAT, LOW COOL and
HIGH COOL.
NOTE: FAN ONLY energizes at LOW HEAT speed. The GPG16 models
are equipped with EEM motors. EEM motors are constant torque
motors with very low power consumption. This motor is energized
by 24VAC. Adjust the CFM for the unit by changing the 24 VAC
leads to the speed terminal block on the motor.
NOTE: Heating airflow must be adjusted to provide the temperature rise shown on rating plate. Blower speeds are programmed to
deliver adequate airflow at rated external static pressure (ESP). Refer to airflow table provided in the Appendix for details.
Limit Check
Check limit control operation after 15 minutes of operation by
blocking the return air grille(s).
1. After several minutes the main burners must go OFF. Blower
will continue to run.
2. Remove air restrictions and main burners will relight after a
cool down period of a few minutes.
Adjust the thermostat setting below room temperature.
1. Main burners must go OFF.
2. Circulating Air Blower will continue to run for 90, 120, 150 or
180 seconds, depending on the setting.
NOTE: If necessary, adjust fan OFF delay settings to obtain satis-
factory comfort level.
WARNING
T
O AVOID PERSONAL INJURY OR DEATH DUE TO ELECTRIC SHOCK, REMOVE
ELECTRICAL POWER FROM THE UNIT BEFORE CHANGING SPEED TAPS ON THE
BLOWER MOTOR.
Speed
Tap
Definition
Lead
Color
Speed
Tap
Definition
Lead
Color
T1
Low
Speed Heat
White T3
Low Speed
Cool
Purple
T2
High
Speed Heat
Brown T4
High Speed
Cool
Yellow
T5
High Speed
Cool Hi-Static
HEATING COOLING