Bath sink smells

We just bought a 2011 Bighorn 3585rl. We have ran a bunch of water through the bathroom sink and every time you turn the water on it smells like sewer water. We are hooked up to park water and this seems to be the only one that smells bad. Is there a way to sanitize the water lines. Any help would be appreciated.

What you want to do is to turn off the park water, drain all of the water out of the water lines using the low point drains, and drain the fresh water tank.

By pass the water heater, then fill the fresh water tank about 1/3, then pour 3/4 cup of bleach in the fresh water tank, then continue filling with water until it is between 1/2 and 2/3 full, pour another 3/4 cup of bleach in the fresh tank, then fill until you get some coming out of the over flow vents.

This will mix the bleach in the water pretty good.

Now, using the water pump (and the water heater bypassed), open one faucet and run water until you have it coming out of both hot and cold (you should smell the bleach), then do the rest of the faucets one at a time, including the inside and outside showers, plus the toilet.

Now . . . best to leave it sit over night if possible (but no less than four hours).

Then drain the fresh water tank and fill and dump twice, then put however much water you like to keep in there, allowing enough to run out to each faucet using the water pump to clear the bleach water out of the water lines.

Now you can turn the park water back on, but don't forget to turn the water heater bypass off.

If this doesn't work, maybe the smell is coming from the gray tank.

Let us know!

Low point drains:



Hot water heater bypass
(note the red & blue pipe with the valve in the middle):

It was mentioned about the Grey tank. Under each sink you have a vacuum breaker valve. They break easy and let Grey water smell out.

You should smell it all the time rather than just when water is running but it could be the culprit and easier to test than bleaching your tanks.

Find the valve and simply unscrew it from the pipe then put some Saran Wrap over the pipe and screw the valve back on. If smell goes away that is your problem.

You can find replacements at any big box store.

Or......just cap the line. This is something I do to each rig I have owned. Plumbing still works fine without it. Just like the vacuum breaker on the black tank flush it is a code thing you don't need.

Well on the black tank flush you should put in a check valve which accomplishes the same thing and they are more sturdy.

Your bathroom sink is right above the water heater so it is the closest. I don't know if that is relevant or not but You need to check the water heater sacrificial anode rod. Be sure to turn off the water supply, allow the water heater to cool then release the pressure before removing that rod.
Depending on previous usage that rod may have to be replaced annually.

Peace
Dave

Another simple possible fix is to disassemble and clean the sink drain pipe. I have done this twice on our 2 year old rig and you wouldn't believe the gunk I got out of the pipe.

We'd put baking soda and vinegar down the drain before we'd do bleach. Put a small box of baking soda into the drain and follow up with a cup or so of white vinegar. Let it foam and sit for 30 minutes to an hour and then pour lots of very hot water down the drain. If you have gunk in the sink pipes, that should clear it. If you've still got a funky smell, then try bleach.

I usually take a hose and blast the sink and shower drains a couple of times per camping season to blow anything that might be stuck in there down into the gray tank.

I also bought some Camco gray tank sanitizer at either Walmart or Camping World that has a 'lemony fresh' scent that seems to work well.

As for bleaching the water lines and fresh tank . . . it is a good idea to do that at the beginning of the camping season anywayz.