Name:	Lifer -	Reply
Subject:	Plumbing/Water Heater Question
Date:	4/22/2014 1:52:19 PM

I have done a good bit of plumbing in the past including installing new and replacing old water heaters but I have a problem that has me a bit puzzled.  The heater in question is between 14 and 20 years old.  I assume it was installed when the house was built in '93 but a major remodel to the house happened prior to my purchase in 2000 so it coould have been upgraded.  The pop off valve went bad 4-5 years ago and I replaced it with no issues till now.  A mildew smell began in the master bedroom closet last week.  Mild at first but grew stronger after a couple of days.  tracked it down to wet carpet so of course I checked for leaks in master bath and the utility closet on the other side of the back wall of the closet.  The pop off valve line runs through that wall to the outside.  I fould find no trace of a leak in it and of course knew that there shouldn't be any water flow through it anyway.  We left the carpet pulled up and put a small heater in to dry the carpet out.  Over the next few days there was no sign of additional leaks.  Then Sunday I checked the drain line again for the 3rd or 4th time and found water dripping at the low point.  Dried it all up and left a dry towel underneath and when I checked it after a while it was wet but not soaked.  Left it in place and checked a few hours later and it was soaked.  I replaced the towel with a bowl and collected very little water Sunday night and Monday.  Looked this morning and there was several ounces of water. I emptied that and was planning a trip to Moore's for a replacement valve but when I looked again to determine what fittings I need it was bone dry.  Through all this I never heard the pop off valve "blow" at all and I never heard of one leaking a little bit.  MY experience is they blow out due to pressure or go bad and leak profusely.  Obviuosly I have a bad joint in the PVC but my concern is the pressence af any water in the line.

So here is my question.  Considering that I have already replaced the valve once should I just do it again or is there a potential problem with the tank that would warrant relacing the whole unit?  It works fine in so much that it heats.  I am really puzzled as to why there is water in the blow off line at all.  Am I missing something?  Any any advice or counsel will be greatly appreciated.

Name:	GoneFishin -	Reply
Subject:	Plumbing/Water Heater Question
Date:	4/22/2014 3:15:29 PM

Not worth investing any money in an old tank.

I would strongly suggest a new tank. The standard warranty with tanks are 6, 9, and 12 years. I replaced 2 in the last few years that were each 12 years old. One was leaking and the other was rusted on the bottom waiting to leak. You are going to have to replace soon so I would suggest now before they start leaking. 

I replaced with GE which are made for them by Rheem. Purchased at Home Depot.

Name:	Shortbus -	Reply
Subject:	Plumbing/Water Heater Question
Date:	4/22/2014 3:42:03 PM

Just wanted to make some water heater info known.

I had my relief valve leaking.

Happened after the regulator out at the street was replaced.

I would come into the cabin and turn on the water heater from cold.

Turns out that the street regulator includes a check valve.  (Water cannot go from house to main)

By heating the water in the checked house system, pressures went to 150# on 100# cpvc.

You can get a pressure gauge that connects to your hose bibb.

Toilet ran, washing machine connection dripped, etc.

Finally installed an expansion tank on the cold side of the heater.

The time a water heater lasts depends on the zinc rod inside.

It disintegrates sacrificially in place of the tank metal.

A 5 year warranty heater has one,  a 10 has two rods.

Just replace every 4 or 5 years and you have a 25 year water heater..............................

If your heater is 15 years old,  get rid of it before the flood.

Name:	MrHodja -	Reply
Subject:	Plumbing/Water Heater Question
Date:	4/22/2014 5:12:18 PM

I would go with a new heater.  I let one go too long in our attic and it cost USAA over $17K to put the two floors under it back into shape.

Name:	John boy -	Reply
Subject:	Plumbing/Water Heater Question
Date:	4/22/2014 5:52:38 PM

One I would replace the water heater but you will have the same problem with a new water heater unless you install an expansion tank on the cold side coming into the water heater. What happens is that you use hot water and cold water comes into tank. This happens about the time that you leave the house and the water heater heats the water which expands and with water lines having check valves. There is no place for the expansion to go but through the pop off valve. The expansion tank will stop this and an additional benefit is that when somone flushes the toilet while in the shower there is less of a change in the water volumn and temp. I had same problem is how I know and plumber explained this to me. Hope this helps.

Name:	Osms -	Reply
Subject:	Plumbing/Water Heater Question
Date:	4/22/2014 6:36:15 PM

One other possibility is the gravity pressure build up from the water supplier's pressure check valve to your house.  When we built, as soon as we hooked up the water heater the pop off valve started leaking, which led us to pressure check the water supply at the house.  Pressure was set at 60 psi at the meter but by the time the water got the 80ft vertically down to the house the pressure exceeded 120 psi.  I had to put another pressure control valve down at the house level to solve the problem.  No problems since.  You might want to  pressure check at the house.