Manufacturer diagnostic code

Back to all Heil N96MSN1002120A**D codes

Heil N96MSN1002120A**D 45.2 troubleshooting

Control failure - gas valve relay will not close. Document the displayed code and operating conditions before scheduling service.

What this code means

The furnace control reports that its gas-valve relay will not close.

Code
45.2
System area
Furnace control board / gas valve relay
Priority
Urgent
Applicable code set
Heil N96MSN furnace status codes (revision 03)

Safe checks

  • Confirm the thermostat is on, set correctly, and calling for heating or cooling.
  • Check the air filter and visible return-air path for obvious airflow restrictions.
  • Record the displayed code or flash sequence before scheduling service.

First step

Record the code, avoid repeated reset attempts, and schedule GreenFlow service.

Frequently asked questions

What does 45.2 mean on a Heil N96MSN1002120A**D?

The furnace control reports that its gas-valve relay will not close.

What should I safely check before scheduling service?

Use only the visible, non-invasive checks listed on this page. Do not open equipment panels.

When should GreenFlow handle this code?

Call GreenFlow if the code repeats, the equipment is locked out, heating or cooling is not restored, or the condition involves gas, ignition, pressure, wiring, a motor, or a control board.

Manufacturer source document