Electrical and Systems
RV Forced Air Furnace Service, Repair and Replacement
Typical range
$350 to $2,500
Shop hours
2 to 10
Labor rate
$260/hr
The short answer
Furnace service covers no-heat and no-ignition faults, sail switch and limit switch failures, board and igniter replacement, duct repair, and full furnace replacement on Suburban and Atwood units. Work runs $350 to $2,500, or 2 to 10 hours at $260 per hour plus parts.
01
What this work actually involves
An RV forced air furnace runs a strict startup sequence and it will refuse to light if any step fails. The blower spins up, a sail switch confirms airflow, the board opens the gas valve, the igniter fires, and a flame sensor confirms ignition. Miss any one of those and you get the classic complaint: the blower runs, nothing gets warm, and it shuts down after a few tries. The single most common cause is a sail switch that will not close because a rodent nest, a spider web in the burner tube, or a collapsed duct has reduced airflow.
Mud dauber wasps in the burner tube are a genuine Southern California problem, and so is rodent nesting in the return path on coaches stored in Riverside, Corona, and the inland valleys. Both restrict flow. High desert owners in Victorville, Hesperia, Lancaster, and Big Bear discover the failure at the worst time, on a freezing night, because the furnace worked fine when it was 80 degrees out and nobody exercised it before the season. We recommend running the furnace through a full cycle in the fall rather than finding out at 2 in the morning.
The other half of furnace complaints is not the furnace, it is the ductwork and the gas supply. Flexible duct that has separated behind a cabinet dumps heat into a wall cavity, so the coach never warms and the limit switch cycles the unit off from overheating. And a furnace that lights, runs for a minute, then drops out is frequently a regulator that cannot hold 11 inches of water column under demand rather than anything wrong with the appliance. We check delivered pressure before condemning a board.
Systems and brands we work on: Suburban, Atwood, Dometic.
Location: All work is performed at our Yorba Linda facility. We do not offer mobile, roadside, or fleet route service.
02
What the job includes
- Full ignition sequence diagnosis from blower through flame sense
- Sail switch and limit switch testing and replacement
- Control board, igniter, and gas valve replacement
- Burner tube cleaning and removal of wasp nests and debris
- Blower motor and wheel service, balance, and replacement
- Combustion air intake and exhaust path clearing
- Duct inspection, reconnection, and replacement of collapsed runs
- Thermostat testing and replacement, including digital upgrades
- Delivered LP pressure verification at the furnace under load
- Full furnace replacement and commissioning
03
When you need this service
- Blower runs but the burner never lights and it locks out
- Furnace lights, runs briefly, then shuts down repeatedly
- Loud rumble, whine, or vibration from the blower
- Warm air at one register and nothing at another
- A burning or scorched smell on first startup of the season
- Furnace runs continuously without ever reaching the set temperature
- Exhaust or combustion smell inside the coach when it runs
04
How we do it, step by step
- 01
Sequence observation
We run the furnace and watch each step of the ignition sequence to see exactly where it stops. That single observation eliminates most of the possible causes immediately.
- 02
Airflow verification
Burner tube, combustion intake, exhaust, and return path inspected for wasp nests, rodent nesting, and debris. Restricted airflow is the most common reason a sail switch will not close.
- 03
Gas pressure under demand
Delivered LP pressure measured at the furnace while it is calling for heat, since a regulator that reads fine at rest and sags under load imitates a failed appliance.
- 04
Electrical and control testing
Board, igniter, flame sensor, limit switch, and thermostat circuit tested individually rather than replaced as a set, because parts on this appliance are not cheap.
- 05
Duct inspection
Duct runs traced for separations and collapses. Heat dumped into a wall cavity makes a healthy furnace look inadequate and overheats the limit switch.
- 06
Repair and cycle testing
Parts replaced, then the furnace run through repeated full cycles from cold to confirm it lights reliably rather than once on a warm bench.
05
Pricing and posted rates
| Item | Rate or range | Notes |
|---|---|---|
| Typical job range | $350 to $2,500 | Varies with extent of damage and parts availability |
| Shop hours | 2 to 10 | Quoted after teardown, not before |
| Mechanical and electrical labor | $260 per hour | 2026 posted rate |
| Parts | 100% markup under $100, 35% over | Special order parts require a non refundable deposit at order |
| Deposit | 50% at authorization over $2,000 | Additional 25% when parts arrive on jobs over $10,000 |
| Sales tax | 7.75% on parts and materials | Labor is not taxed |
Insurance billed jobs may be billed at carrier negotiated labor rates that differ from the posted retail rates above. See all posted rates.
07
Vehicles we do this work on
Vehicle
Class A Gas Motorhomes
A Class A gas motorhome is a flat-front coach built on a Ford F53 or Workhorse front-engine chassis, typically 28 to 38 feet. Rear
Vehicle
Class C Motorhomes
A Class C is a coach body built onto a cutaway van chassis with a sleeping or storage cabover extending above the factory cab. Tha
Vehicle
Standard Fifth Wheels
A fifth wheel couples to a hitch in the truck bed through a kingpin and pin box, with a raised forward bedroom over the truck. The
Vehicle
Travel Trailers
A travel trailer tows from a ball hitch behind the tow vehicle rear axle on an A-frame tongue, which makes it the most sway-prone
Vehicle
Truck Campers, Slide-In
A slide-in truck camper sits in a pickup bed and is clamped down at four points, so it absorbs the truck frame twist directly. Jac
Vehicle
Toy Hauler Trailers
A bumper pull toy hauler carries cargo behind the axles on a ball hitch, which is the worst possible combination for tongue weight
Vehicle
Camper Van Conversions
Camper van conversions are Sprinter, Transit, or ProMaster chassis with windows cut into the sidewalls, a roof full of penetration
08
Questions about furnace service and repair
Frequently asked questions
Why does my RV furnace blow cold air and never light?
The blower runs first by design, then a sail switch has to confirm airflow before the board will open the gas valve. If airflow is restricted by a wasp nest in the burner tube, rodent nesting, or a separated duct, the sail switch never closes and the burner never fires. Restricted airflow causes this far more often than a failed board.
How much does RV furnace repair cost?
Work runs $350 to $2,500, or 2 to 10 hours at $260 per hour plus parts. Cleaning a burner tube and replacing a sail switch is at the low end. A full furnace replacement with duct repair, new thermostat, and commissioning is at the high end. Suburban and Atwood parts pricing drives a lot of the middle.
It lights and then quits after a minute. What is that?
Usually one of two things. Either the flame sensor is dirty or failing and the board is shutting down because it cannot confirm flame, or LP delivered pressure is sagging under demand and the flame is going lean. We measure pressure at the appliance while it runs before replacing anything, because those two look identical from the thermostat.
Should I service the furnace before winter?
Yes, and specifically before a trip to Big Bear, Wrightwood, or the high desert. Furnaces sit unused for most of a Southern California year, which is exactly how burner tubes get occupied by wasps and return paths get occupied by rodents. Running a full cycle in the fall surfaces the problem in your driveway instead of on a freezing night.
Can you replace the furnace with a different heat source?
In many cases yes. A diesel or gasoline fired auxiliary heater is a common alternative on vans and expedition builds because it uses no propane and draws far less battery power than a forced air furnace blower. We can price both paths so you can compare a furnace replacement against a Webasto or Espar installation.
09
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Ready to move on furnace service and repair? Bring it to Yorba Linda.