I was contacted today to inspect a furnace in a mobile home in Morro Bay. This 24 volt version had the wrong propane jet installed and soon after, it was discovered that the tenant had tampered with the thermostat calibration. The occupant was only trying to help fix the first fault. I was able to diagnose both faults, but it required two visits to fully restore this furnace.
Who can repair my RV furnace? RV furnaces are crucial for our winter comfort but they need to be carefully maintained by trained technicians for safety and efficiency.
Common RV furnace faults you may be able to fix:
- Furnace will not start, no fan and no heating: RV Battery may be flat or the RV is not connect to the campground pedestal. Check if the ceiling lights are working in the RV. If the lights are weak or do not switch on, then you either need to connect to the campground power or charge the battery.
- Fan runs but does not heat and the fan automatically shuts down after a few minutes: The propane may be empty. Check if the stove top burner will light. If the stove burner will not light, then it’s possible you are out of propane.
- Fan runs for a few seconds and shuts down: This condition requires the help of a specialist RV Technician.
- Fan keeps running and the furnace does not heat: This condition also requires expert diagnosis.
- Booming or puffing sounds with no heat: Your propane is running low or there may be problems inside your furnace. Try refilling your propane tanks or call your RV repair technician.
If you are unsure about your furnace, contact me today at 805 610 9394 to arrange an appointment to inspect your RV Furnace.
Maintenance tips for your RV Furnace
Furnace Insect Covers: Manufacturers of RV furnaces do not recommend placing insect covers over the intake and exhaust ports located on the outside of your RV. Any restrictions to the intake and exhaust ports may reduce the efficiency of your RV furnace. It is possible that the furnace will overheat and trigger the overlimit switch, and you will need to wait a few minutes for the switch to reset and start the furnace again.
It is possible that many people operate their furnaces with these insect covers installed and have no problems. I do not recommend these covers while using the furnace.
I will install these fine mesh covers on my furnace only when I store my RV for long periods. This prevents insects from building mud nests inside the furnace. As soon as I begin using my RV again, I will remove these insect screens. The same advice goes for RV water heaters. Do not operate your water heater with insect covers, but you may store your RV and install the insect covers safely, removing them when you use your RV again.
Maintenance recommendations for your RV Furnace
- Make sure the exhaust and intake ports are clear of obstructions. Remember the exhaust port is hot and expels as much hot gas as the exhaust pipe of a car. Do not place a table under or near the ports, you might accidentally leave something on the table and it could melt or even self-combust. The obstruction can also overheat your furnace.
- Periodically check the exhaust and inlet ports of your furnace for obstructions inside the ports. With the furnace properly switched off and cooled, shine a bright flashlight into the ports and look for anything inside the tubes. I have seen moths, spiders, spider’s webs, mud nests and even mice inside these tubes. Call a service technician to have these cleared.
- Manufacturers recommend an annual inspection of your RV Furnace. The furnace burns propane and exchanges the heat by the fan cycling the RV’s interior air past a combustion chamber. I have witnessed cracked burn chambers which could leak lethal carbon monoxide to the inside of your RV. A thorough inspection could save everyone inside the RV. Your RV technician can test the furnace for propane leaks too. Keeping your furnace maintained could prolong the life of your RV Furnace.
- Make sure all floor registers are free from carpets, door mats, shoes and any other obstructions. You may also have a furnace outlet on the side of a cupboard, a wall, or on the side of a seat.
- Learn where the furnace return grate is located. Never stack boxes against the register. This will harm the performance of your furnace and possibly trip the overload switch.
- Observe the performance of your RV Furnace: If you notice the furnace operating for longer than normal periodsbefore reaching your set temperature, you may have obstructions in the furnace ducting. In this case, call a certified technician for help.
- Propane and CO alarm: A propane alarm is usually located near the floor somewhere around the middle of the RV and is separate from the furnace. Always have your propane and CO detector operating. Did you know these safety items have a use-by date? When your detector passes the maximum allowed use time, it will beep regularly. This could be telling you it is time to be changed, sometimes it is a low battery charge warning causing this alarm too. I have seen many that are disconnected with cut wires! Always change it out. There will be a date stamp on the back of the detector and a programmed operation period. My detector has saved me many times. Mostly from running my gasoline generator in no-wind conditions. The exhaust accumulates inside the RV and thankfully my CO detector tells me to shut off the generator and go outside for fresh air!
What does an RV furnace inspection include?
Furnace inspections require the complete removal of the furnace. The furnace may be removed from the outside of the RV or in many models, the furnace can only be removed from the inside, in the back of a cupboard or inside a special cavity in the RV’s cabinets. The length of time for removal and installation varies.
When the furnace is removed, the propane must be disconnected. It is possible to cap the propane system so that you can still use the stovetop and hot water heater. The RV technician will be required to perform a leak test for safety. This leak test will take approximately 20 minutes to confirm your propane lines are safe. This leak test will be required again after the furnace is installed later.
The furnace is bench tested, then pulled apart to clean the propane jet or orifice. Wiring is checked for chaffing and the possibility of damage from mice. The fan is inspected for dirt, damage and obstructions. I’ve found mice and even a rat jammed inside these fans! That’s why it’s called a mouse wheel fan!!! Fans are commonly plastic, age and wear may cause the fan to have cracks or even missing vanes. The fan will be replaced if necessary.
If the furnace has been operating properly, then parts in good condition are not replaced.
The air intake and exhaust ports are checked and cleared for dust and bug nests. The furnace will be tipped and shaken to check for anything that may be inside the combustion chamber and burn tube. Rattles will mean there is a nest or something inside. This will be cleaned where possible.
The same burn chamber and heat exchanger will be very closely inspected for cracks. If there is any crack in the heat exchanger, the furnace will need a new core or possibly a new furnace. Cracks can lead to exhaust gases escaping to the inside of the RV and releasing dangerous C0 or carbon monoxide.
The combustion chamber is opened where inspection of the spark / ignitor checks for damage from overheating. The ignition electrode is checked for correct measurements. An incorrect electrode gap will reduce performance or even prevent the furnace from operating at all. A new gasket will be installed and the furnace will reconstructed. After a bench test where the furnace is connected to 12 volt DC power and propane. If the furnace operates properly, the furnace is installed back into your RV and tested again.
This process can take approximately two hours plus travel time where necessary.
How often should a furnace be inspected?
Your RV furnace is recommended to be inspected yearly or before each season. This is the manufacturers’recommendation. A manufacturer may have other recommendations and this would be mentioned in your manual. In areas of high corrosion or high use, where you are located in extreme cold or near the ocean, an annual inspection should be a minimum.
RV Furnaces can have many types of faults. It’s not always the circuit board. Unfortunately some RV Technicians diagnose faults incorrectly. I have been fooled by complex symptoms in a faulty RV Furnace, and a methodical remedial approach is the only way to find a fault. Sometimes there are multiple faults too, which make you revisit the drawing board.
I have had to completely rewire an obsolete furnace where the failed circuit board was no longer available. It was still cheaper than buying a complete new furnace. Another time I had to replace the combustion chamber and heat exchanger because of a crack in the steel casing. Then there was a complete batch of new furnaces in an RV lot which were all returning the same fault. Lucky for warranty!
When you need maintenance on your RV Furnace for the new season, or if you have a fault, don’t hesitate to call me at 805 610 9394 for over the phone support, and where necessary, I will be happy to visit you in your location for closer inspection.
Call 805 610 9394 for advice or book an inspection today!