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Why does my motorhome smell?
Do you have a bad smell in your motorhome? How do you prevent condensation and damp?
We’re here to help with this comprehensive guide to motorhome odours.
If your motorhome or campervan smells of any of the following, then you can fix the problem and prevent it from happening again. Work out where the smell is coming from, or whether it’s a general all over smell.
My motorhome smells of sewage
Cause
Sewer smells in a camper are likely to be an issue with either your motorhome toilet and its’ cassette (sometimes called a black water tank) or your grey waste tanks. Grey water or waste is any liquid waste that is not toilet waste and goes into a holding tank, or series of holding tanks underneath your habitation space. Not all motorhomes have sink traps so sometimes the smell can come back up through the plug-hole.
Action
How do I stop it happening again?
If the problem is with your cassette toilet then:
If the problem is with your grey waste tanks then:
The smell is of sulphur or rotten eggs
Cause
This is either your grey waste tanks or your leisure batteries.
Check your batteries first; if the smell is located in your garage or wherever your leisure batteries are fitted and they are fizzing (you’ll know if they are!) then your battery has ‘boiled’.
If it’s not your batteries then grey waste will be the culprit. Motorhome waste tank smells can be really unpleasant and grey waste that has been sitting for a long time in a sealed container (i.e. your tank) can smell strongly of rotten eggs and sulphur because it has stagnated in the tank. This is often a problem if you’ve been parked up wild camping for three or more days without being able to empty, and then move off with a full or partially full tank of grey waste water.
Action
How do I stop it happening again?
However you manage your leisure batteries, they do have a defined life and will not last forever, but there are steps you can take to prolongue their life.
The longevity of a motorhome or campervan leisure battery depends on frequency of discharge, depth of discharge and how soon it is recharged. A regulator or controller will ensure your battery runs through this charge and discharge cycle regularly. You should not discharge your van battery any more than 50%. To do so can have a damaging effect on the battery and will certainly shorten its life.
Once your new battery is installed, keep an eye; further problems may indicate a problem with either the charging regulator if you have one, or your van’s electrical system. If in doubt, get it checked by an expert.
We are not leisure battery experts and this is a complex field so we’re going to duck out at this stage and suggest you visit this really helpful website where you can find out everything you ever wanted to know about leisure batteries!
My motorhome smells damp & musty
Cause
A damp and musty smell in a camper can be a hard one to know the cause of and there are a number of possible scenarios.
Check for any obvious signs of condensation or mould, particularly where there is also a lack of circulating air; above a pull down bed or beneath sofa cushions for example. Motorhome condensation and subsequent mould is caused by introducing moisture into the warm environment of your motorhome.
This could be from wet clothing if you’ve been out in the rain, the natural act of breathing over night combined with body heat or simply boiling fresh water in the kettle. This moisture becomes trapped in the air and eventually settles inside your motorhome as condensation, unless there is circulating air to move it around and take it away.
Do you always have steamed up windows? Does your bedding feel very slightly damp at night? Do you have small patches of mould? If so, you have ongoing condensation.
Check under your bathroom and kitchen sink for leaking taps, it could be as simple as a loose jubilee clip or damaged seal allowing a trickle to leak from your fresh water tank.
A damp smell could also be caused by a leak externally, where water is ingressing into the construction and fabric of the motorhome. It can take years for this to become noticeable, especially if it’s a small leak, which they usually are.
Action
How do I stop condensation?
There are lots of helpful things you can do to prevent condensation and some you can do to help manage the results of condensation. You can find out more about the causes of condensation and how to stop it in this post.
It smells fishy
Cause
It is highly likely that a fishy smell will be caused by a poor electrical connection that’s been overloaded and is cooking the surrounding PVC and plastic. It could also be caused by cheap fuses overheating and melting the surrounding plastic.
Action
It smells of ammonia
Cause
If this smell is isolated to your fridge then you have leaking coolant, which can be corrosive. You can also check for yellow powdery deposits along the piping at the back of the fridge, the presence of which will confirm a leak. Gas fridges are different to electrically powered fridges as they need a small amount of coolant to keep them working correctly.
Otherwise, the smell may well be connected to your toilet as when urine is stale, it breaks down into ammonia.
Action
Unidentified Smells
There are a couple of smells which are really hard to describe and could be a number of things;
Decomposing pests can be an issue if you have your van in storage and have a double floor. Mice love places like that to nest. If you do find a body, check your wiring carefully as mice also love to chew through cables.
Air conditioning that needs re-gassing has a very specific vinegary/fishy/musty type smell. If this is the case you will also notice that the unit is losing effectiveness.
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