Water heater clacking....

[mrcaptainbob]

Okay, the 2nd floor laundry plumbing is finished. Yes...Hooray and and all that. Now there's a banging as if pipes are bumping. Traced it to the water heater! Every change in water pressure will cause it to rattle. If a faucet downstairs is cracked, it rattles and will also rattle when the well pump kicks on as well as off. Could it be the cold and hot water check valves in the tank top?

[HayZee518]

why do you have check valves in your water heater lines? a mechanical "swinging gate" check valve will rattle a little at low flow, a ball type will vibrate due to water pressure lifting the ball off its seat against a spring.

[canoebuilder]

If you have check valves in water lines it very well could be then chattering, but I don't know why you would have the need for check valves in domestic water lines.?????
Another banging sound not, just a rattle, could be due to undersize water supply lines on long runs of pipe.
To solve this you may want to install "shock absorbers" to take the noise out. I have never had to install one in a domestic but in many reseraunts or condos where the run is over 100 ft it is nessercery.
Gerry

[mrcaptainbob]

Clacking heater.

Are there not check valves in the inlet/outlet ports of the eater heater? What are the red and blue plastic inserts for?

[canoebuilder]

These are only to insure you hook up the cold water to the Blue and the Hot water line to the red.
Gerry

[HayZee518]

quote/ These are only to insure you hook up the cold water to the Blue and the Hot water line to the red/
The blue tube is a "dip tube" and goes all the way to the bottom of the tank. If you'll notice on a gas fired hot water heater the valve assembly is mounted at the bottom, not only because that is where the burner is located but the temp sensor which goes through the tank is there also.

[canoebuilder]

Absolutely right this dip tube creates what is known around here as a Hartford Loop.....By bringing in the cold water to the bottom of the tank the hot water in the tank can not migrate into the cold water pipe.
Gerry

[mrcaptainbob]

Water heater issue.

How about those heat traps? How do they work? Are they mechanical? This noise is bothersome and is most definately coming from inside the tank.

[canoebuilder]

Guess I do not know what you mean my "heat Trap"
Any evidance of water leaking around base of water heater? Air getting into the glass jacket could get the water to boil but in a 100% closed system the water would have to get way to hot to boil.
If your dealing with an electric water heater, you may have a heating element gone hay-wire and over heating...try turning the temp down and see if the problem doesn't help.
Gerry

[HayZee518]

Propane and Natural gas heaters over time develop a scale inside the tank especially at the bottom. If not flushed on a regular basis this scale builds up and may trap air inside - like a bubble - when heated these bubbles expand from the heat and may pop causing noise. The gas burner heats the bottom of the tank much like a tea kettle. Hot water rises to the bonnet and sits there waiting to be used. I don't know what canoebuilder means by the element going haywire. It's either good or bad no in between. The element is a calrod unit. a copper or stainless tube filled with a refractory sand with a nichrome wire [element] inside. the element needs to be fully covered by the water to function otherwise it will always burn up.

[mrcaptainbob]

Water heater.

The heat traps are plastic devices that are in the ends of the in/outs of the heater as -purchased. I suspect them to be the items responsible for this noise. The heater is electric and is brand new, but not using electric as it's run off a heat exchanger from the outside boiler. It will clack even when a location in another part of the house is used and also clacks when the well pump cycles. I'm about ready to take that heater apart and rip those heat traps out!!

[mrcaptainbob]

Water heater....

Ah...HA! Although this goes against everything I am, I broke down and looked at the book that came with this heater. In the "Before You Call For Service" section:
Rattling noise during periods of water usage ~ Internal heat traps in operation ~ This is normal for heat trap fittings when in operation and does not indicate a need for service.
So there it is. Hidden in the book of directions. No wonder I never saw it!

[HayZee518]

I asked lazypup what heat traps were. He said in the dielectric unions are plastic cross pieces cast into the plastic in the form of an X much like what's in your bathtub drain basket. how they function or what they do I have no idea.

[canoebuilder]

All heaters, over time will develope this build up over time.
I had ment to say...a thermostate gone bad not an element.
Any luck with it yet?
Gerry

[mrcaptainbob]

Water heater....

The tank is heated using a heat exchanger, so there are no elements and no flame. (It is an electric heater, though.) As the directions/faq's for the heater state, the heat traps do make noise when operating correctly. But it's still irritating!