fix? smelly showers

[scrubbyfish]

I'm in a place that's new to me, super happy here. The suite had been unused for probably 1.5 or more years before I moved in. Over my time here, the shower room started developing an odd smell. I seem to have narrowed it down to the hot water tank closet, which sits right next to the shower. If during and after a shower I open the door of the hot water tank closet, and open the bathroom window, there is little or no smell. If I leave either of these closed, the smell is present (i.e., has not escaped while developing). The hot water tank closet has pre-existing water damage to its walls and floor.

I'd love to resolve the issue myself, if possible.

Anyone have any thoughts about what might cause the smell, and how to resolve it?

It DOESN'T happen when the hot water tank is just supplying the kitchen sink. So, my guess is either the smell is triggered when LOTS of hot water is accessed, OR is actually coming from the shower drain.

[justajane]

Describe the smell. Does it smell like sulfur? I had a bad drain problem, and I poured a bunch of salt down the drain, followed by boiling water, and this got rid of the smell. You could try that first, and if it doesn't go away, you could at least rule out the drain.

[scrubbyfish]

Describe the smell.

I wish I knew how. It's not a sulfur smell, and it's not awful, not like sewage or something (I had that in a previous home's plumbing, turned out it was a hairline crack from the basement toilet's sump pump, and a quick caulking resolved it).

It's gone right now, so I'll have to check back in with my best go at a description.

[Spondulix]

Could it be mold?

[scrubbyfish]

Could it be mold?

It's entirely possible, but I don't think it is in this case. I'm very sensitive to scents, and will veer quickly from anywhere that has a moldy smell -the laundry room of an apartment two years ago, ex's boat, and ex's trailer all had a smell I assume to be from mold. In those cases, the smell was there pretty much 24/7, even with windows open.

This one is completely absent except for some minutes after showering, dissipating within minutes of opening the window and HW tank door. I just returned from a week away, the whole place shut, and walked in to no scent whatsoever.

I'm reading some theories like this one: http://www.askthebuilder.com/shower-drain-odor/ though that's specific to a drain vs hot water tank closet.

[homehandymum]

Could it be from the insulation or wrapping around the hot water piping?  Perhaps as the hot water goes from the tank and through the pipe, it heats it up and it somehow gasses-off?

Your description of when you smelled it reminds me of when I smell gas in my in-law's house - their hot water is gas-heated, and I can often smell gas when someone begins running the hot water and it fires up.  But if you have an electric system, then it won't be gas, but it might be some other hotness-related / water-heating related smell, rather than a wet water/drainage smell.

Or maybe something has been spilled in the hotwater cupboard that gasses off when heating up?

[Zombie Burger]

Most water heaters have a relief valve that is directed to a drain. If there is a drain there, the trap could be releasing gasses if it is dry. If you find such a drain, try pouring some water into it.

[scrubbyfish]

Tank is on electric, not gas.
No drain visible, but I think there must be one, so perhaps it's behind the tank.

I ran the shower and observed what I could.

No active leaking that I could see.
Definitely (pre-existing) water damage to walls and floor, and some black coloured mold -with no apparent scent- on one wall.

The smell was relatively faint this time.
I couldn't pinpoint where the smell was coming from, but it doesn't seem to be from the floor, the spigot, any of the other interesting points on the tank, or the walls.
Most concentrated at the tank itself, between it and the wall shared with the shower.
The smell is not sulfur or otherwise particularly foul. My best go at a description is that it's a bit "sweet" and along the lines of a lightly smelly shoe, or sweaty hockey gear (hate that smell), wet dog hair, or a rug that's been left out in the dirt and rain.

[MsPeacock]

I"m not remotely a plumber - but I think water tanks have a drain/valve. The tanks can get sludge/sediment/build-up on the bottom - so maybe draining it off would possibly help?