Occasional Low Hot Water Pressure

[Supreme1]

Hi,

I have a problem with the hot water pressure.

Many times after I flush the toilet, the hot water pressure (at the faucets) slows to a trickle. Once the toilet tank is full, there is a loud bang in the pipes and the hot water pressure (at the faucets) increases back to normal pressure. The toilet tank only has a cold water pipe connected to it.

Also, sometimes (like this morning) when I turn on the hot water (at any faucet) it initially flows at normal pressure but immediately slows to a trickle and remains like that for a while. Then I hear a bang in the pipes and the pressure returns to normal. This happened without flushing the toilet.

Any ideas what is causing this?

 

[Liq]

your lines are galvanized i wager??


Sounds to me like you have line restriction. what happens is a venturi is formed ( low pressure in the line ) and then BANG the pressure returns to normal and then repeats the process, this would happen whenever a fixture is used regardless of hot or cold as your hot water tank is supplied by a cold feed initially.

I have also had something like this happen on a hot water tank in a friends house, it was an electric tank and the atmospheric breaker was allowing air into the tank during this process which also led to burping at the fixtures..

this is My best guess, others may offer different insight.

 

[Supreme1]

Sorry I didn't mention it before. MY lines are copper. The hot water tank is gas.

I am confused about why the hot water pressure drops when I flush the toilet, since the toilet is only connected to the cold water. This leads me to suspect the problem is related to the hot water tank, because that is the only location where the hot and cold lines are connected.

 

[johnjh2o]

Do you have a pressure reducing valve? I have seen them cause the same problems that you are describing when they need service or replacement.

John

 

[LiQuId]

Very wise observation ^

never thought about that one.

 

[johnjh2o]

Off subject but I'm glad to see you got your password reset Liquid.

John

 

[havasu]

Off subject but I'm glad to see you got your password reset Liquid.

John

Me too, I felt helpless without the ability to do anything except pick up the hot line to Admin (Austin!).

 

[LiQuId]

thanks guys, As i've taken a mental health day today I have enjoyed a mornin sleeping in ( 14 hour days all week this week ) but the plumber in me must fix something, lol. So that old kitchen tap is no more...