HVACopedia

NTI · Boiler

NOAVL PCB error: boiler application not set

Medium severity TRX

What the control is telling you

Parameter 046 is set to UNDEF. Clears once the issue is corrected.

Applies to: TRX150

Likely causes

  • Parameter 046 left at UNDEF
  • Short on the eBus2 wires

Test and repair steps

  1. Set parameter 046 for the boiler application: b--SIN for single boiler (default), b--MAS for cascade master, b--FL1 to b--FL7 for cascade followers 1 to 7.
  2. If the problem continues, check the eBus2 wires and make sure they are not shorted together.
  3. If the problem still continues, replace the main control.

Models that show this code

5 models in TRX

TRX085TRX110CTRX150TRX199TRX199C

Other codes on the same units

  • 5 P3 Flame loss during run
  • 5 P6 3rd and 4th ignition failed
  • 06 02 Exhaust temperature above 204 °F (96 °C)
  • 06 03 APS open
  • 06 05 Exhaust NTC circuit open or short circuit
  • 6 12 Insufficient fan speed
  • EMERG Incorrect wiring to BUS connection (emergency mode)
  • FILL - 108 Low water pressure lockout

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Source: NTI TRX150 manual, p. 87. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.