Dometic Sail Switch Problems

A sail switch is a very important component for the safety of the electric appliances on your RV. It saves you and your RV from lots of dangers. The Dometic sail switch is among the top favorite sail switch and has done a great duty for lots of people.

However, there are some issues with this switch as well. If you ever face problems with the Dometic sail switch it can be dangerous at times depending on what kind of problem you face.

That’s why you should know all the details about this sail switch problem and how can you solve them.

Dometic Sail Switch Problems
Dometic Sail Switch

Common Problems and Fixes of Dometic Sail Switch

Normally the Dometic sail switch does not show any problems. However, there are always some exceptions that can happen. Here is a list of common problems of Dometic sail switch-

1. Shutting off Unexpectedly

Due to its lack of a filter and its placement beneath refrigerators or in other low-lying areas, the air supply chamber is an entry point for dirt, trash, and other debris.

This may result in the sail switch, being filthy and unable to notify the furnace system that the propane may be ignited safely.


If you are facing this problem, you better not try to open the system and try to fix it all by yourself. Because there are lots of things closely linked to it.

Thus, you should talk to a professional for cleaning and fix the problem.

2. Furnace Blowing Cold Air

Whenever there is cold air coming from the furnace instead of heating it you should know that there is something wrong with the sail switch.

The sail switch often stops working when there is a low battery and stops the ignition process. Hence, when you are trying to switch on the furnace it is not working.

This may be the main problem of the furnace but it originated in the sail switch. That’s why you need to know about the main issue of the faulty furnace.


The main fix for the problem is to recharge your battery. but if the battery is not charging anymore you have to think about testing it. If you have the proper equipment to check if the battery is good or has gone bad, you can do it at home.

However, you can also take it to a battery shop for checking and replacement.

3. Damaged Sail Switch

If your sail switch is totally out then the furnace will not work. And sometimes the whole electric system will stop functioning. The damaged sail switch can turn out like that if there is a short circuit or something happened like an electric surge, etc.

You can always see that when the Dometic sail switch is down it is not in a condition of repair.


There is only one fix to this problem and that is changing the sail switch. When a sail switch dies there is not much that you can do about it. You can try to repair it. But the cost-benefit will always tell you that instead of trying to repair it, you should buy a new one.

Because when you are out traveling on a cold winter night and if the sail switch that you repaired stops working that will be a serious issue.

How To Bypass The Sail Switch?

Now if your sail switch is down and you cannot turn on the furnace it would be a big issue and there is a way to fix it. You can bypass the sail switch which will reduce the safety but it will provide you the service you need for the time being till you get to fix the sail switch. But remember that it can be quite dangerous and may need expert hands to move and fix it. Here is how you do it-

First, remove the furnace from its position. Remember to turn off the gas line otherwise, it will fill your RV.

Always be cautious while removing the pipes and the wires because they can be quite fragile. And if you accidentally rip off any wire it can cost you later.

Remove the sail switch from the furnace and you will get two wires. After that, you can use tape to connect those wires to the generator line. This can be quite dangerous and it is advised that you do not attempt this because there are plenty of wires and connections and different models have different types of systems.

If you have connected the generator to the furnace, it should work now. And you can enjoy the warm air on a cold night.

However, you should always contact a professional for any help with the sail switch as electric and fire-related systems can be dangerous.

Frequently Asked Questions (FAQs)

How do you test a sail switch?

If you need to test the sail switch. close or activate the sail switch manually, and then link the multimeter’s red and black pins to the switch’s two contacts. As long as the sail switch is open, the multimeter shall display “OL” (open line). Shut it manually before beginning the measurement.

What activates a sail switch?

A sail switch is turned on or off in reaction to the airflow or lack of a fluid, like air or water. Usually, a blade or a diaphragm, which is moved by the pressure of fluid or air passing by it, is used to control a sail switch.

What does a sail switch do on an RV furnace?

A sail switch is a tool for air testing. It serves as a protective feature and won’t allow the ignition to start till it detects 3 quarter of the motor’s rpm. It guarantees that the ignition disk is spinning quickly enough for the right amount of air and gas to be mixed together for a seamless ignite.


A Dometic sail switch is a great option for your safety switches for a furnace or another electric device that needs ignition. Also, it is quite durable and there are very few cases where it breaks down.

However, if you have trouble with your sail switch you should check why it is happening and if necessary, take professional help.