A water heater mystery

Ted Keane

I'm a plumber in Park City,Utah.I have a water heater that was installed on the 3rd. floor of a townhouse.I had to replace it because it was leaking.When I saw it,the top of the heater was crushed in,and the bottom was buldged out,and it was leaking.This is the 2nd. one in 4 years that has done this.It is a Bradford White 50 gallon gas water heater,and this one is only 2 years old.I thought it was from overheating,but the diptube and relief valve and the nipples are not melted.The owners have never left the house,so they didn't drain the system down.The flue is 3 feet long,and all clear.The water pressure is 70 psi,and the gas is 4 ounces.I can't figure out what happened.Bradford White wouldn't warranty the last one that did this,so I'm sure they won't warranty this one either.The only thing I can see that is different,is that the cold water backfeeds through the laundry valve,so the ball valve on top won't shutoff the water.To drain it I had to shut off the whole house.Anybody have any ideas?

Chris V

Water Heater

Sounds like it imploded due to a sudden loss of water pressure. Is there a backflow device on the water main? I would install a vaccuum breaker at water heater.

jim lockard

Water heater

Thats what I was wondering Chris Could a fire pumper have pulled a negative pressure or a water main break in the street have caused this ? Ted is there a backflow preventer or check valve meter in the system ? do you have an expanion tank on the system? Have any of the other water heaters in the area had this problem? J.Lockard

kevin coppinger_4

Jim is on to...

the problem. a Vacuum relief valve is need (watts N36) and a potable water expanation tank made just for water heaters. kpc

hr

Being in the mountains

Park City and Deer Valley has dozens of PRV, and booster stations on their water system.

There was a time when the city's fire insurance carrier required them to exercise booster pump ocassionally, in place on the system for fire protection flows, if needed.

We knew when they exercised these because we get flooded with calls of our fire protection pressure relief valves popping and blowing out glycol or glycerin. These pumps would spike the pressure in the mains for a brief period when the revved up.

The fire sprinkler connections were always before the buildings PRV's.

I suppose if your job is on the intake side of those large booster pumps you could in fact see a temporary vacumn.

Or the Resort has their snowmaking water pumps connected to your line

Rich at City Waterworks knows, if he is still there

hot rod

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

Larry Weingarten

pressure

Hello: I've had flues collapse because the tank was hooked up to multiple washing machines that had quick closing solenoids. Water hammer, over time can do it. The bottom of the tank bulging suggests high pressure, if only for split seconds at a time. The flue connected to the top and bottom would have to pull one to follow the other. I use a recording 24 hour pressure gauge to help troubleshoot "mysterious" heaters. You could just put a gauge on the drain valve and watch it while having the various hot water uses cycled through their paces. Also, don't assume the delivery pressure remains constant. Being close to a pumping staton or near the end of a main line can cause interesting problems. The relief valve is not a good indicator of pressure either, as they get stuck pretty often. Hope that helps.