Black Smoke Coming Out Of RV Hot Water Heater

by Cheryl Teeple
(Clarksville Iowa)

Properly Maintaining Your RV's Water Heater

Properly Maintaining Your RV's Water Heater

We started the hot water heater, it started fine but there's black smoke coming out of the heater from the outside vent. It ran fine until it shut off cause the water was hot and it went out. It did start back up when we turned the switch on again.

It hasn't been used for a long time. We're thinking it needs a good cleaning but can't figure out how to get the screen off. I'm just not sure about the black smoke coming out, it got on the side of the trailer also the water has a bad odor like rotten eggs only on the hot water we're confused and need answers.

ANSWER: Hi Cheryl, since you don't tell me the year, make or model of your RV nor the make or model of your RV's water heater, I am going to explain things in general terms about RV Water Heaters. First and foremost, the fact that you are seeing black smoke coming out of the water heater compartment is not normal, and you should not try to run the water heater again until this problem is resolved.

The most common causes of the smoke in an RV water heater can be something as simple as a spider or other insect nest in the burner tube or burner chamber of your RV's water heater, or even the water heater running at too rich of a setting. My initial suggestion is based on some of the questions you have asked me, that you take your RV in and have a Certified RV Technician inspect and repair the water heater.

If you do feel comfortable, you can do some routine maintenance on the water heater yourself to see if that resolves the problem. Just follow the steps below.

First, you have to get access to the water heater by removing the water heater cover located on the outside of your RV (pictured above). Depending on the type of cover used you may simply have to twist a little camlock ring and open the water heater door, on other types of covers you may have to remove some screws on the cover to gain access to
the water heater.

The video below does an excellent job of walking you through the basics of the routine RV water heater maintenance process.

Camping World
Shop Camping World Products on Sale Now!

A couple of notes here: If you do not have access to an air compressor, a can of compressed air should be sufficient to dislodge any insect nests from the burner tube or chamber.

Also if you happen to have a Suburban Water Heater, do not skip the important step of replacing the Anode Rod (pictured above).

The reason an Anode Rod is required by a Suburban Water Heater is because the tank of the Suburban Water Heater uses glass enamel over a steel tank. If the enamel cracks for any reason it will expose the steel to the water and the steel will start to corrode even from a pinhole in the enamel. The rod attracts the corrosive elements in the water that could corrode the water heater tank and the rod itself gets corroded.

The Anode Rod is part of the Suburban Water Heater's drain plug. It should be checked at least once a year and should be replaced when half of the rod has been corroded away.

So why doesn't the Atwood need an Anode Rod? The water tank on the Atwood Water Heater is made of aluminum which does not have the same corrosive properties as steel.

Over 1,500,000 successful roadside rescues—Good Sam RV Emergency Road Service

Now let's address your concerns about the smell of the water coming out of your hot water heater. The odor could be in the case of a Suburban Water Heater that the Anode Rod has been totally consumed and the tank is rusting out or just from stagnant water that has been in the hot water tank and lines for a long time. Hopefully flushing out the water heater will resolve the odor problem.

If after you have performed all the above routine maintenance, you still have a smoke or soot problem with your water heater then it will be time to take your RV in and have a Certified RV Technician tackle the problem.

I hope that this information has been helpful to you.

Comments for Black Smoke Coming Out Of RV Hot Water Heater

Average Rating starstarstarstarstar

Click here to add your own comments

Hot water tank cleaning
by: Anonymous

Camco wants to sell any gizmo and gadget to unwary owners.most of those gadgets you don’t need.the video explains a marine engineer I know that if you do regular routine maintenance like draining your tank and replacing the anode you won’t need the "gadgets".most of these things are very doable for the average rv owner.with a little know how and some patience you can fix,repair or replace anything.

Black smoke
by: Anonymous

Hang a flea and tick collar from a non-heat pricing source in the compartment. This will keep spiders out. This works in your refrigerator compartment as well.

Similar Problem
by: CJH

I had a similar issue. Unfortunately I didn't realize it until I noticed black soot up the whole side of my trailer above the heater. Thankfully I was able to polish it out.

My burner was not burning clean and I was getting a yellowish flame that was extending up into the exhaust duct. I figured it shouldn't need air adjustment since it had worked properly in the past. I felt there must be a problem with the propane supply or regulator. I also recalled my wife mentioning earlier while cooking that the outdoor kitchen burner was working but not kicking out the level of heat it should. I disconnected both my propane tanks from the main pressure regulator and then reconnected them. This then resolved my issue. I continue to monitor it but so far it hasn't happened again. It appears to have been a sticky regulator or a pressure lock of some kind.

black smoke
by: Jon

I have an Atwood hot water heater I bought about 8 months ago. When I turned everything on, I noticed water dripping from the hot water heater. I called the technician and he said it was nothing to worry about. Now there is black smoke coming out of it and it shut off. The installer came out to look at it and said I didn't tell him the water was dripping from the igniter area. He said that means the tank is cracked and I need a new hot water heater. He reminded me that I bought the heater online and if I bought one from him it would have been guaranteed.

Flushing debris
by: Allrite RV Center

What the video failed to mention is that most all water heaters fill up with solids from suspended minerals in the water. While the drain plug/anode rod is out you should flush the tank until all chunks of minerals are cleaned out. Camco makes a device for the end of garden hose to do this with, available at most any rv parts dept.

ALSO, you can use a garden hose to rinse the soot and any rust or debris from the heat "tube" in your water heater. Good way to clear out insect nests etc...

Click here to add your own comments

Return to Ask an RV Question.