Hot Water Heater Pressure Question

**clovis** · #1 07/08/10, 07:55 PM

I'm in the process of fixing up an old house that has sat vacant for about two years.

The gas and water were shut off, and the Indiana winters froze the water lines in the house.

We've patched the plumbing system, and no longer have any water leaks.

We don't have tons of pressure in the hot water lines, but have plenty of water pressure on the cold side.

Is it common to have low pressure on the hot water lines if the gas 40 gallon water heater isn't turn on?

Does a tank type water heater build pressure in the lines?

Thanks in advance!!!!!!

**Ross** · #2 07/08/10, 08:21 PM

Does it have a tempering valve adding cold water to the hot at the tank? Is it shut off?

**clovis** · #3 07/08/10, 08:34 PM

I'm not sure...I'll have to check.

artificer · #4 07/09/10, 06:30 AM

The hot water lines should have almost the same pressure as the cold lines. More piping, so a small drop, but it shouldn't be noticeable.

Things to check for:
shutoff valve before/after the water heater thats closed
Cracked water heater tank thats leaking
Open drain at the bottom of the water heater
plugged lines

Michael

**clovis** · #5 07/09/10, 08:00 AM

Quote:

Originally Posted by artificer

The hot water lines should have almost the same pressure as the cold lines. More piping, so a small drop, but it shouldn't be noticeable.

Things to check for:
shutoff valve before/after the water heater thats closed
Cracked water heater tank thats leaking
Open drain at the bottom of the water heater
plugged lines

Michael

This is not what I wanted to hear...

The tank is not leaking...at least there is no water on the floor, and hasn't been to my knowledge.

I'll double check the shut off valves.

I'm wondering if it is plugged lines somewhere. I've had that problem in my own home. I replaced some galvanized pipe with copper, and must have shaken some rust loose, which almost destroyed the flow of hot water to my kitchen faucet. We've just lived with the problem, but the water flow has improved tremendously over time.

Thanks so much for your time and expertise!!!!!!!!!! I appreciate it!!!!!!!

artificer · #6 07/10/10, 01:29 AM

Quote:

Originally Posted by clovis

Thanks so much for your time and expertise!!!!!!!!!! I appreciate it!!!!!!!

No problem, I like to help. The real thanks is when you find out what the problem is, and then post it. Many people never come back and finish the thread with the results.

One thing to check is to trace the cold water supply to the source. Sometimes you'll find a valve in a weird place.

Michael

texican · #7 07/10/10, 01:11 PM

You didn't accidentally get something in your hot water lines when you were patching it?

**clovis** · #8 07/10/10, 06:27 PM

That is definately a possibility.

The house is about 1/2 ancient galvanized, with the balance in quality, newer copper, and now a little pex.

There could easily be a rust glob in the lines.