Reznor UDAP User Manual (English)

Questions and Answers:

R
ryanweberJul 30, 2025
What to do if the venter motor on my Reznor UDAP will not start?
- L
  Lynn GayJul 30, 2025
  If the venter motor isn't starting, first, ensure the unit has power and check the supply fuses or circuit breaker. Verify that there's 24-volt power reaching the integrated circuit board by turning up the thermostat and checking the control transformer output. Inspect the integrated circuit board fuse and replace it if blown (use type ATC or ATO, 32VDC, 3A after correcting the cause). Tighten connections at the circuit board and/or motor terminals to ensure power is getting to the venter motor. If these steps don't work, the integrated circuit board or the venter motor itself may be defective and need replacement.
J
Justin KingAug 8, 2025
What causes a Reznor UDAP fan or venter motor to cut out on overload?
- C
  Crystal RichAug 8, 2025
  If the fan or venter motor cuts out on overload, it could be due to a low or high voltage supply, which needs to be corrected. A defective motor can also cause this issue, requiring replacement. Poor airflow could be another reason; try cleaning the motor, fan, fan guard, filter, and coils.
R
Rhonda LeeAug 12, 2025
What causes a Reznor UDAP Heater fan or venter motor to turn on and off while the burner is operating?
- T
  Tina KingAug 12, 2025
  This issue can occur if the motor overload device is cycling on and off. Check the motor load against the motor rating plate. If the load exceeds the rating, consider replacing the motor.
H
Helen Campbell MDAug 16, 2025
Why is there no heat when my Reznor Heater is operating?
- F
  fvasquezAug 16, 2025
  Lack of heat while the heater is running could stem from a few reasons. The valve outlet pressure or orifice might be incorrect; check the valve outlet pressure against the rating plate for manifold pressure. It could also be cycling on a limit control, so check the air throughput. Finally, the thermostat's location or adjustment might be improper; consult the thermostat manufacturer's instructions.
A
adamspaulAug 20, 2025
What to do if the fan or venter motor will not run on my Reznor Heater?
- C
  Christopher LewisAug 21, 2025
  If the fan or venter motor isn't running, first check the wiring and connections for any open circuits. If the wiring is intact, the integrated circuit board may be defective and need replacement. Alternatively, the motor or starter itself might be defective, requiring replacement.

Reznor UDAP Specifications

General

Model	UDAP
Type	Unit Heater
Fuel Type	Natural Gas or Propane
Efficiency	80%
Ignition System	Direct Spark Ignition
Vent Type	Power Vented
Thermostat	Optional
Dimensions	Varies by model
Weight	Varies by model
Installation	Horizontal or Vertical
BTU Range	30, 000 - 400, 000 BTU/hr
Voltage	115V