If you are looking for RV furnace troubleshooting guide you are in the right place! We will help you in dealing with different issues related to ignitors, air vents, RV furnace fan, or thermostats.
So, continue reading to learn about the methods to detect problems via error codes, the 7 often problems, and their solution. Also, scroll down and you will find a diagram that will help you understand the RV furnace.
Let’s get started!
Table of Contents
Working Mechanism of an RV Furnace
The main principle of working in a furnace is burning fuel (usually propane or natural gas) to produce heat. Several components make up the whole forced-hot-air system. The components are:
- A thermostat
- An RV furnace control board
- A relay, a sail switch
- A blower motor
- A high-level switch
Here is a detailed overview of its working!
- First, you must set the thermostat to a higher temperature than the indoors.
- Once this is done, the furnace works by activating the RV furnace blower motor.
- Airflow starts to circulate into the RV. After about 15 seconds the control board detects (through the flame-sensing rods) and ignites the propane.
- The burning propane produces warm air through the process of combustion which is distributed through the RV ductwork to the different parts of the RV.
Understanding the RV Furnace Diagnostic Codes
Diagnostic codes communicate the malfunction or problem occurring in the system. They signify the problem with a flashing LED on the furnace panel. The number of times the light flashes needed to be counted accurately to record a code. It is more like a Morse Code!
The interpretation of the code can be found in the owner’s manual or on the sticker present on the furnace. Listed below are the very common codes:
- Code 31
- Code 32
- Code 33
- Code 34
The interpretations of the codes are mentioned below. Let’s learn more about them!
What does Code 31 mean?
The following code identifies a problem with the airflow. Common reasons for the problem are a dirty filter, a faulty RV furnace blower motor, or even a blocked intake of air.
What does Code 32 mean?
If you encounter this code then it means that the ignition system in the furnace is problematic. Check the electrode for any dirt deposits, a weak spark, or a fault with the gas valve.
What does Code 33 mean?
This flashing code communicates that a safety mechanism has activated shutting down the furnace which is usually due to a malfunction in the heat exchanger. This happens when the limit or flame rollout switch trips.
What does Code 34 mean?
A problem in the furnace’s ignition sequence generates this error code. Check if you notice any blockage on the burner opening, a fault in the gas supply outlet, or any issue with the ignition control board.
RV Furnaces: 7 Common Problems and Their Fixes!
After some time you may likely face certain technical problems in the RV furnace. Here are some common problems that you may encounter and their solutions. Let’s have a look!
1. RV Furnace Isn’t Functioning Properly
You may turn the furnace on and it does not work. This happens due to several reasons some of which are failure to channel power from the 12V battery. Also, coordination between the thermostat and furnace results in such an issue.
2. The Fan Works Perfectly but Heat is Not Produced
You notice that the furnace blower fan is on but the heat does not come out. Instead, you notice cold air coming out! This happens when there is a problem with the ignition, sail switch, the circuit board is causing problems, or the fuel is not igniting.
3. The Furnace Stops/Starts from Time to Time
Two major faults cause this problem! Firstly, a damaged thermostat. Secondly, a problem with the environment surrounding as the temperature of the air might be higher than expected. Warm air may hit it directly. It will record that airflow as the room temperature and shut down.
4. The Thermostat Temperature Setting is Right but the Furnace Stays On!
Sometimes the desired temperature is achieved but the furnace keeps working and does not shut off. In such a situation, more heat will circulate in the RV and the situation can get out of hand due to high temperature.
5. The Furnace Doesn’t Work via Battery
The 12-volt battery is the main source of power for the furnace. But, if the battery fails to supply enough charge but the furnace functions perfectly with a shore power/generator. Then the common reasons are that the battery is not charging, is faulty, or the terminals are corroded.
6. Extremely Weak Air Flow via Duct/Exhaust Vent
This problem is due to blockages, holes in the exhaust vent/duct, or improper/loose fitting. Air-escaping leakages will not distribute well in the RV.
7. Loud Noises Coming from the Fan
Check the blades of the furnace fan if they are hitting the housing. Another reason could be debris, lint, or any other collection of unwanted stuff. Check the fan motor if it has a loose or damaged bearing.
RV Furnace Blower, Heat Exchanger, and Other Essential Parts
Knowing the functionality and parts that make up the whole RV furnace system is essential knowledge. Understanding the different parts allows you to identify them while troubleshooting errors. Listed below are some important parts of the RV furnace. Let’s learn more about each part!
- Air Return: Takes in the air to circulate through the heat exchanger and then out of the ducts.
- Blower Motor: Motors are used to operate fans for the circulation of air through the furnace.
- On/Off Switch & Circuit Breaker: They control the power to the blower motor. Circuit breaker trips in case of any issue for example short circuit.
- Combustion Air Intake: Located on the external end of the RV it pumps air into the combustion chamber.
- Combustion Chamber: Propane and oxygen combust here to generate heat for the furnace.
- DSI: DSI (Direct Spark Ignition) is an electronic ignitor that generates a spark to burn the gas-air mixture.
- Ducts: They circulate heated air coming from the furnace into the interior of the RV.
- Exhaust: Throws out poisonous gases produced during the combustion process via the exhaust vent.
- Fan Speed Controller: Controls the speed of the fan and adjustment of BTU output.
- Heat Exchanger: Warms the air in the ducts by taking heat from the combustion chamber via conduction.
- Gas Valve: Controlled by the circuit board, this valve is electronically controlled to release gas into the combustion chamber.
- High Limit Switch: Regulates the heat and ensures that the heat exchanger does not get damaged. It cuts the power if temperature readings are above the limit.
- Igniter: Produces a spark to initiate the burning of propane. In a DSI furnace, it is present instead of a pilot light. It is also a sensor to detect successful ignition.
- Pilot Light: Ignites a small flame constantly lighting any propane when the valve is open. Note: Ansebt in a DSI furnace.
- Sail Switch: The sail switch stops the air from the blower. When the blower goes fast, it moves it away, so power can go to the ignition switch.
- Thermostat: The thermostat checks how hot it is inside the RV. If it's not hot enough, it turns on the furnace to make it warmer.
- Time Delay Relay: It waits for a short time before starting the furnace cycle. [/su_note]
Standard Diagram of RV Furnace Wiring System
The furnace diagram will help you locate all the important components and their connections. Here is a diagram to help you out!
Some of the most common RV furnaces problems can be identified with the furnace shutting down within 30 seconds, the furnace does not turn on when the thermostat is adjusted, the furnace blowing cold air, the fan spinning but propane does not burn, and so on.
How do you troubleshoot a furnace problem?
The best way to troubleshoot a furnace problem is by identifying the problem either by understanding the code or by physically inspecting the furnace system. Certain indications will give you hints about the source of the problem such as no ignition, less airflow, etc.
Why will my RV furnace not ignite?
The RV furnace ignitor does not work due to some common problems with the onboard batteries. They must have worn out or got damaged for some reason. Also, the circuit breaker can trip as a safety measure so which also causes this problem.
How does RV furnace work?
RV furnace working depends on the type of furnace for example some RV furnaces operate by blowing hot air from the faceplate of the device. A ducted furnace will circulate air via ducts that channel through the ceiling or flooring.
Is RV furnace AC or DC?
The RV furnace system runs with the help of a 12V DC battery. Although, it can also run via a shore power source or a generator.
Troubleshooting the furnace consists of identifying the root of the problem and resolving it. It ensures that any further damage or malfunction does not occur in the furnace.
Common problems like cold air flow can be resolved by checking the ignitor or ignition board. Damaged ducts can be another problem that can be easily fixed using duct tape.
But if you are unsure of the methods then getting help from a professional is the best approach. Which error code did you encounter and how did you resolve the problem? Let us know in the comments section if the problem was fixed!
I`m a current Law Enforcement Officer working within the Counterterrorism Bureau in New York State. I have been Camping for over 20 years. My styles of camping include tent, car, truck, van, and RV travel trailer. I have a YouTube channel where I teach all types of camping with an entertaining method: https://youtube.com/@TheSmallsRVAdventures