RV furnace not working: the check, the cause, and the cost

An RV furnace that will not ignite or blow warm air is a common cold-snap call in Montgomery County, and it is rarely something that needs a whole new furnace. Most repairs run $200 to $800.

Check this first (five minutes)

Check battery voltage. An RV furnace needs a healthy 12V supply to run its fan, ignition control, and gas valve. Weak batteries after months in storage are one of the most common causes of a furnace that seems totally dead.
Listen for the sequence. Fan starts, pauses, then either ignites or does not. If the fan never starts at all, suspect power or the thermostat before the furnace itself.
Check the exterior intake and exhaust vents. Blocked by debris, a wasp nest, or storage-yard dust, these will prevent ignition entirely as a safety measure.
Note whether you hear clicking with no flame. That points to the igniter or a gas supply issue, not the fan or blower.

What is usually wrong

What you find	Likely cause	Fix and cost
Nothing happens at all, no fan	Weak batteries or thermostat fault	$150 to $400
Fan runs, no ignition attempt	Sail switch not detecting airflow	$200 to $500
Clicking, no flame	Failed igniter or gas supply issue	$200 to $500
Blocked intake or exhaust vent	Debris, insect nest, or storage-yard dust	Clear and test: $150 to $300
Runs briefly then shuts off	Overheat safety trip, often a blower or airflow issue	$250 to $600
No response of any kind, board appears dead	Failed control board	$300 to $800

Ranges from the pricing page, on top of the $75 to $150 trip fee and $125 to $190 hourly labor.

Why this happens after a Montgomery County storage-yard sit

A furnace that only runs a handful of cold nights a year in Texas spends most of its life sitting unused, and insects find their way into exterior vents and burner tubes during that idle time the same way they do in a water heater. Add a battery bank that has weakened from months of no real charging cycle, and a furnace that worked fine last winter can seem completely dead on the first cold night of the season. A pre-winter check of battery voltage and a look at the exterior vents catches most of this before you need heat.

What to expect on the call

Tell us whether the fan runs, whether you hear clicking, and the battery voltage if you can check it. We work on site across Conroe, Montgomery, Willis, The Woodlands, Magnolia, New Caney, and Huntsville. The appliance repair service page covers furnace, fridge, and 12V repair in more depth.

Frequently Asked Questions

Fan runs but no heat. What is that?

Usually the sail switch (which confirms airflow before the burner is allowed to light), a failed igniter, or a gas supply issue. It is rarely the fan itself. A meter and a look at the burner tube narrows it fast.

The furnace worked fine last winter and now nothing happens when I turn it on. Why?

A furnace that has not run since last winter, especially one that sat in a humid Montgomery County storage yard through summer, commonly has a corroded connection, a blocked burner tube, or a battery too weak to open the gas valve and run the fan. Check battery voltage first.

How much does furnace repair cost?

Most repairs run $200 to $800: sail switches, igniter boards, and blower motors toward the lower half, a full control board or blower replacement toward the top. We diagnose before quoting either way.

Does furnace work require a special license in Texas?

The gas side does. Texas requires a Railroad Commission of Texas Category M certification to service or repair an RV's LP-gas appliances and piping, which includes the furnace's gas train. Ask any tech to show that certification before they work on the gas side.