Tjernlund GPAK-J,JT,1,1T (Discontinued) 8504013 Rev 3 09/97 - Manual (Page 13)

OPERATION CIRCUIT CHECK
1. After all appliance and GPAK wiring is complete, establish 115V power to the appliance and Power Venter with the appliance
thermostat/aquastat not calling for heat. NOTE: If using the GPAK-JT or GPAK-1T the Power Venter may operate when power is
first established, wait until the Power Venter shuts off before continuing.
2. Adjust the appliance thermostat/aquastat to call for heat. At this point, the Power Venter should start. After a slight delay, the
appliance burner should fire. The delay is caused by the Power Venter Fan Proving Switch. The delay will be no more than 4
seconds, if you are unable to detect a slight delay, contact Tjernlund Products, Inc. at 1-800-255-4208 for assistance.
A) Wired to gas valve: When the Power Venter Fan Proving Switch closes, the circuit to the gas valve is completed.
B) Wired to thermostat: When the Power Venter Fan Proving Switch closes, the furnace combustion relay is energized, Normal
combustion sequence for the furnace begins: Induced draft furnace blower starts, its proving switch makes
energizing ignition control and/or gas valve.
DO NOT OPERATE THE APPLIANCE WITHOUT THE FAN PROVING SWITCH WIRED INTO THE 24V APPLIANCE CIRCUIT!
3. Adjust the appliance thermostat/aquastat so that no heat is required. At this point the Power Venter and appliance should shut off.
NOTE: If using the GPAK-JT or GPAK-1T, the Power Venter will continue to run for a non-adjustable time of approximately 45
seconds after the appliance burner shuts off.
COMBUSTION AIR
Adequate combustion air is vital for proper combustion and for safe venting. Likewise, for proper GPAK performance, adequate com-
bustion air must be available to the appliance. Many installers assume adequate combustion air is present, especially in older homes.
In some cases this is a false assumption, because many older homes have been made "tight" due to weatherization. Size the com-
bustion air opening(s) into the appliance room as outlined NFPA 54/NFPA 211. Tjernlund’s IN-FORCER
TM engineered combustion air
intakes provide a convenient, interlocked way to supply combustion air to the utility room. When installing a GPAK it is not necessary
to supply any more combustion air than normally required when conventional venting.
SAFETY INTERLOCK/COMBUSTION AIR TEST
The Power Venter Fan Proving Switch is designed to disable the appliance gas valve upon Power Venter failure only! It is not
designed and cannot replace, regular vent system inspection, appliance servicing and combustion testing.
1. Close all doors and windows of the building. If the appliance is installed in a utility room or closet, close the entrance door to this
room. Close fireplace dampers.
2. Turn on clothes dryer and all exhaust fans such as range hoods, bathroom exhausts and whole house fans to maximum speeds.
(Do not operate a fan used strictly for Summer exhausting).
3. Following the appliance manufacturer’s instructions, place the appliance in operation, set thermostat for continuous operation.
4. Allow fans and appliance to operate for 5 minutes.
5. Test for spillage at the appliance draft hood, draft control or draft diverter relief opening using the flame of a match, candle or
smoke from a cigarette, cigar or pipe and determine the following:
A) The flame or smoke is being drawn into the draft hood, draft control or draft diverter.
B) The main burner is burning properly, i.e. no floating, lifting or flashback. Adjust the primary air shutter(s) and Power Venter air flow
adjustment as required.
C) If the appliance is equipped with high and low flame controlling or flame modulation, check for proper main burner operation at low
flame, (See Diagram G).
If the draw of the flame or smoke appears to be excessive, follow the “Air
Flow Adjustment” procedure outlined on page 13.
6. Sign and date these instructions to verify that the safety interlock /
combustion air test was completed. These instructions must
remain on premises.
SIGN:____________________________________
DATE:_____________________
12
DIAGRAM G