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Poor hot water pressure

I just moved into a house that has very poor hot water pressure everywhere except the drain on the hot water heater itself. The house has been re-plumbed with (PEX) piping everywhere except a three inch section of galvanized pipe on the "out" of the hot water heater. Could this galvanized section be plugging?

Re: Poor hot water pressure

This galvanized piece may actually be a heat trap nipple. If the nipple was installed incorrectly (upside-down or swapped with the one on the cold side) that could explain the problem. Or, the heat trap could be corroded, blocking the flow. If it's just a nipple, replace it with a brass nipple.

Heat traps work like this: on the cold side, there's a floating ball that floats up and blocks the pipe when no water is flowing in order to stop convection currents into the supply line and thereby reduce heat loss. On the hot side there's a marble that sinks to perform the same task. When water flows, it pushes down the float and lifts the marble allowing the water to pass.

If either of these traps are installed incorrectly, water flow will cause the marble/float to block off the pipe.

Blue RidgeParkway
Re: Poor hot water pressure

See the last Q&A section on the bottom of the this page (click link)


Note: a Shut off does not belong on the outlet side of a water heater

When you drain off water from the bottom of the tank do you hear it refill? is this refilling a trickle or a woosh?

Do you have a tempering valve on the output?
Recirculation system, if so check temperature of return lines.

Re: Poor hot water pressure

Thanks 4 help, I'm assuming that its just a piece of galvanized tubeing and not a heat trap because there is nothing on the cold side, unless the heat trap looks exaclty like any regular galvanized pipe? The water is hot when it comes out at the sinks, washer, bathtub, etc. The water flow is just terrible. The water heater is farely new, I'm going to try to see if I can here the water going into the tank. I kind of hope that it is not that galvanized pipe, it looks like its goin to be a pain to change it without breaking sumthing. :( Will report findings, when found

Re: Poor hot water pressure

All the heat traps I've seen -- and I haven't seen them all -- have a circumferential groove around the middle of the trap. If it doesn't have this groove, chances are it is just a nipple installed to make things fit.

I've learned to hate galvanized pipe for water supply lines. :mad:

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