Save 50% Off of Campsites with Passport America

Bad Smell From the Cabin Heater in My Class C Motorhome

by Anonymous

Bad Smell From the Cabin Heater in My Class C Motorhome

Bad Smell From the Cabin Heater in My Class C Motorhome

It does not have an antifreeze or burn smell. Is it possible to get mold or mildew in heat vents and duct? Would this be easy to check and rectify?

ANSWER: Hi thanks for submitting your question on our Ask An RV Question Page

Leave your RV repair bills to us—Good Sam Extended Service Plan

Yes mold or mildew can form on the Air Conditioner evaporator or in the AC evaporator box in your motorhomes chassis cabin heater/AC system. You will be able to smell this musty smell when using the cab heating system.

Based on your description I cannot guarantee that what you are smelling is from Mold or Mildew. Here are a couple of things I would check before I started attacking the AC Evaporator. Depending on the year of your motorhome the Heating/AC system on your motorhomes chassis may have a cabin air filter. You should check this filter and change it as needed.

Another thing to check is the drain hose on your AC Evaporators box. There should be a small drain hose on the box that allows the water created by the evaporator to drain on the ground. If this hose is blocked the evaporator box will retain the water and create a great environment for Mold and Mildew growth. Obviously you are going to have to climb under the engine compartment of your Motorhome to locate the the evaporator box drain hose to make sure that it is not blocked.

OK now for the bad news, the only way to really be sure that the smell you are smelling through the heater is Mold or Mildew is to take your motorhome in and have a mechanic open up your AC/Heating system and inspect the AC evaporator and vent system for Mold and Mildew growth and thoroughly clean the system.

There are Automotive AC/Heating System Cleaning Products available that claim they can get rid of the Mold and Mildew and their related smells without opening up the AC/Heating Systems. I have never used these products so I cannot tell you if they will work or not. If you decide to use one of these products I urge you to read the instructions carefully before using them.

Other causes of bad smells in the cabin heating systems could be coming from the engine compartment, an electrical component in the AC/Heating system that is failing, a leak in the heater core, food items that may have been inadvertently dropped in one the systems vents or even a little insect or rodent that may have crawled into the system and died.

I hope that this has helped.

Do you have any suggestions or comments on this topic? You can add them to this page by clicking on the "Click Here To Post Comments" link located near the bottom of this page.

Happy RVing

RVing Al

Good Sam RV Parks: Top Rated Parks Across the Country. Listings on Over 2,100 RV Parks!

Click here to post comments

Join in and write your own page! It's easy to do. How? Simply click here to return to Ask An RV Question.

Recommended Reading For You







Good Sam Roadside

Good Sam Travel Assist

Click Here