Hot water heater

[Witzend]

What does the water smell like if you have a small leak in the engine coolant ellement inside the HWH? I'm getting a very acrid smell, only in our hot water. I'm also loosing a very little bit of ethylene glycol each time we run the engine for a few houres. No detectable leeks otherwise. I'm thinking it is going into the domestic hot water. We generally do not leave the domestic water system pressurized when we leave the boat, but the engine coolant would still have pressure on it allowing it to migrate into the HWH. Anyone ever have that happen?

 

[Bill Roosa]

Car radiator smell

Even strongly diluted coolant smells. With your car engine cool take off the radiator cap and sniff. That is the smell

 

[alexco38]

Dye-Lite

Put some Dye-Lite into the coolant and see if the hot water glows under UV light.

http://www.dangerden.com/store/uv-water-dye-lite.html

Usually, the loop in the HWH tank is nothing but a loop. It is unusual to develop leaks but possible.

May be you have a coolant circulating pump leaking around the oil seal. There is a very small weeping hole to show coolant leak before the oil seals breaks.

 

[berner73]

Had the exact same problem about 6 weeks ago. I replaced the 23 year old hot water heater and the smell went away (as did the very minimal consumption of AF).

Before tearing everything apart, I bypassed the HWH circuit and monitored the AF consumption.

 

[FastOlson]

I agree that a leak in the heat transfer loop inside the tank is very very rare. Even so, we switched to Sierra brand antifreeze a long time ago because it's non toxic.

If your hot water tank is 20+ years old, it's probably time to replace it anyway, and while you're at it, source one with a SS inner tank. The aluminum tanks leach a white powdery corrosion into your water supply. Ick.

L

 

[Witzend]

I like the isolation test, I will try that first.

 

[Benny]

Rotten egg smell? Likely cause is bacteria in tank sediment fed from hydrogen gas created from decay of sacrificial anode. Tank should be treated with 1/3 pint of 3% peroxide to 6 gallons of water.

 

[Dan Johnson]

Hey Witz...

also, what's your source of water? We have well water over at my club and it adds a distinct odor to the water coming out of the hot water tap after sitting in the potable water tank for a month or two. I have a whole house filter between the tank and pump the take out anything otherwise.

 

[woodster]

Rotten egg smell? Likely cause is bacteria in tank sediment fed from hydrogen gas created from decay of sacrificial anode. Tank should be treated with 1/3 pint of 3% peroxide to 6 gallons of water.

wouldnt that also indicate a high sulpher content in the water???????.....

regards

woody

 

[Witzend]

Could be hydrogen sulfide Benny, although seems more acrid and less rotten egg. I will check the PH. The tank manufactures never seem to put the drain from the bottom, always from the side, so it is not possible to completely drain.

 

[Stu Jackson]

Then there's this

http://c34.org/bbs/index.php/topic,5836.0.html

 

[Witzend]

Thanks Stu for the great link.
I figured out an efficient way to reverse flush just the HWH, since that was where the problem was.
1) Heat up the water as hot as you can this will tell you when you have displaced all the water when flushing by the temp. change.
2) Depressurize the system by opening all the HW facets.
3) Connect a washing machine inlet hose, (a 6’ length with two females) to the HWH drain valve.
4) Connect a water source to the washing machine inlet hose.
5) Turn on the water and check for leaks.
6) Open up the drain valve on the HWH.
Water should now be coming out all the HW faucets.
6) Let run until water is cold, and then some more.
7) Turn off the valve at the HWH.
8) Turn off the water source.
9) Disconnect the water source from the washing machine hose.
10) Drain the water out of the washing machine hose.
11) Use a funnel and pour a cup of Clorox into the hose and connect the water source back up while keeping the Clorox from running out by keeping it elevated.
12) Turn on the drain valve on the HWH.
13) Turn on and then off, the water source for just a few seconds, enough to displace the Clorox in the hose into the tank.
14) Turn off the valve on the HWH.
15) Turn off all the HW faucets.
16) Disconnect the hoses.
You're probably wondering why go through all this?
I did not want to run my fresh water pump to death flushing out the HWH. I also just wanted to inject the Clorox in higher concentrations in the HWH only, the cold water was fine. Worked great!