Modern RVs rely on Dometic furnaces for reliable heating on the road, but a tripped reset switch can halt comfort. This article explains what the reset switch does, how to locate and safely reset it, and how to troubleshoot recurring trips. It covers model variations, practical safety steps, and maintenance tips to minimize nuisance resets, helping owners restore heat quickly while safeguarding equipment.
Understanding The Dometic Furnace Reset Switch
The reset switch on Dometic RV furnaces is a safety device that interrupts operation after overheating, flame failure, or electrical faults. In many models, the reset appears as a small red button or a momentary switch on the blower housing or control board. When tripped, the furnace will not ignite until the switch is reset and the system has cooled. Knowing where it is and how it functions helps distinguish a simple reset from a deeper equipment issue.
Safety Precautions Before Reset
- Turn off power at the RV’s disconnect switch and shut off the propane supply to the furnace before handling any components.
- Allow the furnace to cool to prevent burns from hot surfaces or metal parts.
- Do not bypass safety devices, remove the access panel while the unit is energized, or attempt to operate with exposed wiring.
- Keep children and pets away from the furnace area during inspection and reset procedures.
- Use a flashlight and insulated tools if needed; do not use metal tools to press internal switches unless the manual specifically instructs so.
- If there is a strong gas odor, evacuate and contact emergency services before proceeding.
Locating The Reset Switch On Common Dometic Furnaces
In most Dometic furnaces used in RVs, the reset switch is near the blower assembly behind the service panel. It may be a recessed red button on the control board or a small toggle labeled RESET on or near the blower housing. Some models require removing the front or bottom access panel to reach the reset component. Since layout varies by model and generation, consult the owner’s manual or a model-specific diagram if available. If the manual isn’t accessible, carefully inspect the furnace cabinet for a red or pink reset component behind the panels.
Step-By-Step Guide To Reset The Dometic Furnace
- Power down the system: switch off the RV’s power supply and shut off the propane gas line to the furnace to ensure a safe reset.
- Gain access to the reset area: remove the appropriate service panel as required by the model, keeping screws in a secure container.
- Locate the reset switch: find the small red button or toggle labeled RESET on or near the control board or blower housing.
- Execute the reset: press and release the reset button once, then wait 30–60 seconds for the system to cool slightly and the switch to reset. If applicable, allow 1–2 minutes for the thermal limiter to regain stable temperature.
- Reassemble and restore power: reinstall the access panel, reestablish the gas supply, and turn power back on. Set the thermostat to call for heat and observe ignition and operation.
- Monitor the furnace: if it trips again, stop and proceed to troubleshooting rather than forcing another reset.
| Symptom | Likely Cause | Quick Action |
|---|---|---|
| Furnace won’t ignite after reset | Flame sensor dirty, gas supply issue, or control fault | Inspect and clean flame sensor, verify gas valve operation, verify venting |
| Repeated trips during ignition | Overheating due to restricted airflow or vent blockage | Check air filter, ductwork, and exterior vent clearance |
| No ignition but blower runs | Lockout from flame-failure or ignition failure | Check ignition system and gas supply; confirm flame is establishing |
| External panels warm to touch | Overheating or poor airflow | Inspect blower, heat exchanger, and vents for blockages |
Troubleshooting If The Reset Doesn’t Resolve The Issue
Even after a successful reset, recurring faults require systematic checks to identify underlying causes. The following steps help pinpoint issues without bypassing safety features. If none resolve the problem, avoid continuing to operate the furnace and contact a qualified RV technician.
- Inspect air intake and exhaust paths: remove debris, ensure unobstructed airflow, and verify exterior vent screens are clean.
- Evaluate air filtration and ductwork: replace dirty filters and check for closed or blocked dampers, leaks, or poor seals that hinder airflow.
- Verify propane supply and regulator: fluctuating gas pressure or restrictions can trigger flame-sensing faults; ensure hoses and connections are intact and odor-free.
- Assess the flame sensor and ignition system: buildup on the flame sensor or worn igniters can prevent reliable ignition; cleaners or replacement may be required per model guidelines.
- Check electrical connections: inspect for loose wires, corrosion, or damaged connectors on the control board and blower assembly; reseat or replace as needed by a technician.
- Review error codes: many Dometic boards display codes to indicate issues; consult the manual for exact codes and recommended actions.
Preventive Maintenance To Minimize Reset Trips
Proactive maintenance reduces nuisance resets and extends furnace life. A regular routine should include air filter replacement every 1–3 months, depending on use and environment; periodic blower and fan cleaning; vent and exhaust inspection for blockages; checking seals on all ductwork; and annual professional inspections to verify gas pressure, heat exchanger integrity, and electronics alignment. Keeping a maintenance log with service dates, model numbers, and observed symptoms helps diagnose future problems quickly.
When To Call A Professional
Repeated reset trips or initial ignition failures warrant professional assessment. A licensed RV technician can diagnose gas valve and regulator performance, flame sensing reliability, venting integrity, and electrical control issues with appropriate testing tools. Seek immediate help if a strong gas odor is detected, if ignition fails after a safe reset, or if the unit has suffered water damage or flood exposure. Do not override safety features or perform electrical repairs beyond basic reset procedures.