I have galvanized pipes. If the hot side outlet of the water heater is clogged, will that shut down a water heater? Put in a new water heater and fired it up. After an hour there was so much condensation at the burner it shut it down. Had plenty of air flow but did notice that the hot outlet side pipe was clogged with rust to a pin hole.

why would having a clogged pipe be any different than keeping the faucets closed ?
has no effect whatsoever.

Okay that makes sense. Of course now I have no idea why I can't keep the burner going to heat the water.

does the control have a blinking light that blinks in sequence to give you information ?
in this picture it is called a 'status light'.

ALL heaters will "condense" in the central flue when they are full of cold water. IF the condensate drips on to the pilot light, it WILL shut down the heater.

So maybe I should drain off half the tank. It runs good for an hour but then there is so much condensation it literally drowns the flame.

Yes it has this display and it blinks every two seconds just like it says it should.

"It runs good for an hour but then there is so much condensation it literally drowns the flame."

that usually indicates a poor draft.

There is a vent hole in the ceiling that looks like it was used for the heater but whoever put in his last water heater tied the heater and water heater together. So I will separate the two again. If that does not do the trick I can always cut a hole underneath the water heater for more air flow around the burner. Thanks Packy

the lack of make up air does not cause condensation.
the lack of a good draft will.
the flue gas needs to be warm enough to create an upwards movement. (warm air rises)
the warm air also carries away moisture.
think of the exhaust on your car.
when the exhaust pipe is cold, water drips out of the end.
when it gets nice and hot, the water is still there but it is absorbed.
this is why very efficient gas appliance vent thru PVC or stainless steel.

So as I thought the galvanized pipes were completely clogged. I repiped the house fired up the water heater and had no problems with it at all. Thanks all for your input.



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