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Gas Hot Water Heater - Low Water Pressure and Pressure Release Discharge?

Gas Hot Water Heater - Low Water Pressure and Pressure Release Discharge?


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Old 08-02-14, 09:15 PM
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Gas Hot Water Heater - Low Water Pressure and Pressure Release Discharge?

We just purchased a foreclosure this summer. Built in 2005. It was winterized in April and was only empty for a few months during the spring. I immediately noticed that the pressure release valve in the hot water heater was discharging small amounts of water after we moved in. I have a small bucket that catches the water for now. Also noticing that the hot water pressure is low throughout the house in the baths and faucets. Any ideas or suggestions to find the problem and correct it?
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  #2  
Old 08-02-14, 09:24 PM
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It is a Ruud Guardian System. Model PH2-50-40F. 50 gallon gas hot water heater.
 
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Old 08-03-14, 02:01 AM
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I don't see an expansion tank on the cold water supply to the heater, that is probably the reason for the T&P valve "burping" occasionally. For the low pressure I suspect that you have a Pressure Reducing Valve (PRV) in the main cold water line that has had the adjustment set low.
 
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Old 08-03-14, 06:41 AM
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It seems to only leak when we use hot water in the dishwasher, washing machine, or bath. The thing about the pressure is that the cold water pressure is excellent throughout the house, but the hot water pressure is terrible. I would say 25% hot water pressure to 100% for cold water. That is what has me puzzled ...
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  #5  
Old 08-03-14, 07:31 AM
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You need to check the PSI of the water in the home. Get a gauge from the home store that attaches to a hose bib.



Take a pic of the water main and look for a PRV like this..



You most likely need an expansion tank installed.

As far as the low pressure on the hot it may be smaller pipes in the wall, say 1/2"?? A valve that's part way closed? Some type of blockage?
 
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Old 08-03-14, 08:55 AM
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If the cold water pressure is good, I wouldn't think a pressure regulator on the incoming water line would be at fault. How about a TEMPERING valve on the hot water line somewhere? Have you followed the hot water piping all the way (what you can see anyway) from heater to fixture?

What's that heater sitting on? What I can see in the pic doesn't really look all too sturdy. That's not just a couple boards slapped together is it?

This really should be in the " Water Heaters " forum.
 
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Old 08-03-14, 09:01 AM
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I wouldn't think a pressure regulator on the incoming water line would be at fault.
Not for the low PSI of hot water..correct!! But I am trying to determine if its a closed system for the sake of an expansion tank...
 
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Old 08-03-14, 10:14 AM
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I don't see any type of tempering valve on the hot water coming out from the tank. The base is a sturdy metal stand. I did notice the hot water pressure starts off strong then fades throughout the house. Thanks for all the replies!

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Old 08-03-14, 10:26 AM
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On the cold inlet side to the water heater... follow that pipe back to where it comes from... look for a partially closed valve.

This still would not account for the pressure release though.

What Mike said about the pressure reducing valve... if there is one, or you have a water meter with a built in check valve, you are going to require an expansion tank installed on the cold inlet side of the water heater.

I presume that the first pic you posted is taken after the 'clutter' had been removed from the top of the heater? Just sayin'... the top of a water heater isn't a good place to store stuff and could be a fire hazard.
 
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Old 08-03-14, 05:51 PM
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I have checked the water lines and haven't found anything. I have a yellow shut off handle for the water line to the entire house and another on the cold water inlet to the water heater. Both are fully open and I opened and closed them both several times. Wondering if I should drain the tank ...
 
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Old 08-03-14, 06:27 PM
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Wondering if I should drain the tank ...
In hopes of finding what? It won't hurt to drain it I suppose.

What you might be able to discover though...

Hook a hose to the drain and leave the water turned on.

If the water coming from the tank drain does NOT decrease in pressure and comes full blast, then you know that there is some 'blockage' between the water heater outlet and the fixtures.

If the water coming from the drain does the same thing as the fixtures, you will know the 'blockage' is on the inlet side.

You've looked underneath all the insulation on the pipes for valves, etc?

Modern water heaters have 'heat trap' nipples built into them. They are actually part of the water heater. I believe it's possible for those to get blocked.

If that water heater was sitting and turned off for months, theoretically there could have been some 'crud' growing inside.

I'm thinking the flow problem is the heat trap nipples... read this:

Tanklets: Water heater heat trap issues

but you still might need an expansion tank installed.

Pick up one of the gauges that Mike showed... they're about ten bucks or so. It will record the highest pressure it sees (the 'lazy' hand). When you use a lot of hot water and the heater fires up to reheat the tank, that cold water will expand and if no water is used in the home to relieve the pressure build-up, the pressure could be going over the setting of the water heater relief valve.
 
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Old 08-03-14, 07:10 PM
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Remove the pipe insulation at the tank connections and show us the pipe material and connections... May be steel and that is your issue...

What year is the heater?

Those steel nipples corrode and close up..
 
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Old 08-03-14, 07:35 PM
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Here are some pics of the cold water and hot water lines going into and out of the top of my gas water heater. The cold water inlet has the one piece the attaches and goes through my drywall. Not sure what that is?
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Old 08-03-14, 07:48 PM
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heater was installed in new house in 2005
 
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Old 08-03-14, 08:08 PM
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IMO if you cant find any other blockage of closed valves the the nipples at the heater should be removed and inspected...

Since you have good cold psi then the sink aerators most likely would not be clogged...( I always say clean the aerators when low flow to both H/C...)
 
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Old 08-04-14, 04:12 PM
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Will these from Lowes work? Utilitech 2-Pack Dielectric Nipple with Ht Trap $11.78
 
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Old 08-04-14, 05:41 PM
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Yes.. I usually pull the heat traps out with a screw driver..............
 
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Old 08-05-14, 08:20 AM
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Yes.. I usually pull the heat traps out with a screw driver..............
I'm not quite sure how the heat traps are supposed to work, but it looks to me like they pose a restriction on both lines. As long as water can flow through the heat traps, even at a slightly reduced rate, it looks to me like heat will still migrate up both lines. Also, not quite sure how these can be considered dielectric since I see continuous steel nipple from bottom threads to the top threads.
 
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Old 08-05-14, 09:27 AM
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Read here Joe.........................

What Is a Dielectric Nipple?
 
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Old 08-05-14, 05:47 PM
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The heat trap contains a small ball or flap that settles down when no one is using water and is heavy enough to prevent eddy currents of water from migrating both up and down the same pipe, causing heat loss.

When someone uses water, the ball is light enough to move out of the way and not impede the flow, unless there is crud in its path.

Even though you are complaining about low hot water pressure, when each new tankful is heated, the water expands and for a moment increases the system pressure enough to trip the relief valve. An expansion tank cures this problem.

When draining the tank, turn off the water heater heat. If you lose track and drain too much water out and the water heater kicks on, components inside could self destruct. Refill the heater to the point where a hot water faucet upstairs is gushing before turning the water heater back on.
 
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Old 09-06-14, 03:04 PM
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I removed the hot water nipple and it was ok. I was worried. We turned the water main back on and water started coming out of the hot water pipe that we cut which leaves the water heater. I thought the hot/cold pipes were reversed when connecting to the water heater. We then checked the cold water nipple and it was clogged. Replaced both nipples and reconnected the pipes. I now have hot water pressure throughout the house! Thanks for all the great advice! It only cost me a bottle of wine as payment to my co-worker who sweated the pipes back together. Thanks again ...
 

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Old 09-06-14, 08:53 PM
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Too bad your co-worker didn't add unions to the piping so that when the heater needs replacing it wouldn't be necessary to cut and solder the piping AGAIN.
 
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Old 09-07-14, 01:31 PM
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I could have used that advice ... YESTERDAY
 
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Old 03-11-15, 02:40 PM
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I was still having pressure release discharge after baths, laundry, dishwasher, etc. Finally figured out the old owners installed a big irrigation system which closed off the water system. Installed a Utilitech 2-Gallon Expansion Pressure Tank today and all the hot water problems seem to be gone. I can now set the water heater to a hotter temp without it releasing hot water every time we shower, do dishes, etc. Thanks for all the advice, I think I finally solved all the problems

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Old 03-11-15, 03:35 PM
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I was still having pressure release discharge after baths, laundry, dishwasher, etc. Finally figured out the old owners installed a big irrigation system which closed off the water system. Installed a Utilitech 2-Gallon Expansion Pressure Tank today and all the hot water problems seem to be gone.
We did state this in the begging posts by Furd and myself...

Glad its fixed....
 
 

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