Expansion Tank

John Penwarden_2

Here's an interesting one for homeowners. I live in NE PA, next door to my sister-in-law. My house used to belong to her father and her house used to belong to her Aunt (Fathers sister). Only difference in the heating systems for the houses is that hers is a single zone heat only and mine is 4 heating, plus DHW via indirect. Both houses have oil-fired crown boilers and diaphragm expansion tanks. She called me the other night to ask about a horrible smell coming from the basement. We looked but could not find it, but it was rancid, acrid and was leaching into her living area. She called again the next night to ask about the expansion tank. How do you "purge a system". I asked why she had to do that and she said that she bought a new expansion tank and the directions said to purge the system after installing the tank. I walked over to have a look and found the existing tank had failed. The tank is the small diaphragm type with air on bottom, water on top. The seam between the two sections was covered in a sticky-gooey dripping mess and stunk like crazy. In about 20 minutes I had the old tank outside and the new tank installed (she had bought an identical model). Question is what was the smell? Was it the release of the stagnant air from the bladder? Was it the combinatin of the air reacting with the water? The old tank (which was only about 6 years old) looked like a pot on the stove that boiled over. Now all is back to normal and the smell is finally gone.

Alan(CaliforniaRadiant)Forbes

X-tank

Good question on the x-tank as I have also noticed the smell coming from the air side of the tank, even on new ones when we have to let a little air out.

It must have something to do with the material they use for the bladder.

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"

Dale

Smell Like a swamp

I have always thought the answer was that like a stagnant swamp the closed system has little oxygen and that certain smelly bacteria like that.