Water heater question

[butchrobbins]

I have been trying to use my 110v hot water heater after having the water out of it. It is filled up now. However, whenever I turn it on, water comes from the temperature/pressure valve. The Manual says "This temperature/pressure valve may weep during initial operation. This normal. The valve will seat itself with use." My questions are:
1) How long should this thing weep? It goes through gallons of water and never seems to seat.
2) If I use it intermittently, will this happen every time I turn it on?

thx

 

[Rich Stidger]

PT valves will sometimes weep but should stop with not more than a couple ounces of water expelled.

If yours is dripping or passing water continuously, you can try opening and closing the valve manually. Flipping the lever and letting the valve "snap" closed may help. If this doesn't stop the flow, the valve needs to be replaced.

I can't say if my PT valve weeps each time because I have it plumbed to my bilge. However, since my fresh water pump doesn't run when I heat up the water, I don't think the valve weeps at all.

 

[butchrobbins]

Thx Rich-I think I need to replace it. I have tried flipping the valve to quickly open/close and it still does it. Guess I'll have to replace it.

 

[Ron20324]

Don't know how much the whole valve cost, but is the seat itself replaceable, like in a home faucet?

 

[Steve Dion]

I suggest that you just replace the valve. Not sure that there is any difference between the ones on a home unit or in the boat, but cheap non-the-less.

http://www.westsidewholesale.com/pressure-relief-valve-for-tankless-water-heaters.html

 

[Rich Stidger]

The PT vlave is a $10-12 item.

The bigger problem is being able to have access to get a big pipe wrench on it an get it loose. The original valves are often sealed with pipe putty that is sometimes hard to break loose. I wanted to replace mine two years ago (then 10 years old) and when I couldn't get the original one out without removing the entire tank, I decided that the 10-year old tank was close enough to end-of-life that I simply replaced it with an exact duplicate.

Oh, yes, I don't believe that there is any difference between a PT valve for home or marine use. They both perform the same function in a similar piece of equipment.

 

[Stu Jackson]

The PT vlave is a $10-12 item...Oh, yes, I don't believe that there is any difference between a PT valve for home or marine use. They both perform the same function in a similar piece of equipment.

That is correct. Only additional suggestion is to flap the handle WHEN the water is spitting out, not just at rest. What happens often is that a small piece of debris can get into the seat and keep it open, which is what your definition of your issue was in your original post. If that doesn't work, dow what Rich suggests. Rector's pipe dope is good material for (re)seating valves on threaded pipes, available at hardware stores all over, small white cans with red highlights, screw off cap with brush.

 

[DeniseO30]

tap on it after you flip it open. sometimes that will help it re-seat. they are cheap to replace. ck the temp setting on the thermostat I doesn't need to be higher the 140.

 

[Don12364]

Its Got to Go Somewhere!

A 6 gal steel tank full of water at room temp when heated to 150°F will expand by a little under half a pint. The system is already under between 30 psi and 50 psi from the pump and the flexible tubing will already have any spare volume taken up - so the additional half pint has to go somewhere - normally it vents through the valve
Unless there is an accumulator in the system this will occur every time the heater is switched on from cold - or the engine is run from cold.
Suggest looking at the valve when the tank is cold and the water pump is pressurised to see if it is dripping.

 

[Ron20324]

I just got a new Attwood water heater, but I'm away from home and dealing from memory. I believe the instructions said to not turn on the heater, but run the water system until some water comes out of the hot faucet (though not hot water yet). When it does, shut off the water and open the pressure valve until water stops coming out. Then shut it.This allows some expansion in the tank.

 

[butchrobbins]

thanks Ron, I'll give that a try.

 

[jibes138]

I just installed a new Raritan 6 gal.

I had replaced my OEM Raritan after about 17 years with a unit called brand X, The brand X was a little smaller so I could get it through the cockpit lazerette top without taking half the boat apart and removing the engine. big mistake, the lower cost unit sprung a leak after only about 5 years. The new Raritan I just installed noted that when full there is a small amount of air left at the top of the tank. The outlet fitting is not flush or out of the top so some air is trapped. It is actually a good thing IMHO because it has an accumulator effect. The Raritan literature notes the air will be absorbed eventually by the water.
As for the valve my original heater the valve used to stick a bit and every once in a while the thermostat would go haywire and overheat this would trip the internal breaker and also cause the overpressure valve to open. A light tap on the end of the stem of the valve would allow it to seat. The problem wasn't with the valve seat, rather it was the valve shaft to the flip lever would stick and not allow it to fully close. A light tap on the end and it would fully close. For the rare time this happened it wasn't worth the aggravation to replace. You might want to try a light tap on the end to see if it works.

 

[butchrobbins]

thanks dave....I will try that too.

 

[agaliha]

Marine is different

I had to replace the Pressure release valve on the water heater in my boat last year. I learned that the marine valve has a lower release pressure than a "household" valve from the hardware store. It is also about 5 times the price and very hard to locate. I finally found one at Defender.
As is often the case, using non-marine stuff might not be the safest.
Agaliha

 

[butchrobbins]

Thanks guys. I tried the easy suggestions and I ran out of time before I can make the final judgement. Tapping on it seems to slow it down, but not sure yet if it will stop. Am going to check it again Wednesday.

 

[jibes138]

Try this

Since it has activated many times the water will then evaporate leaving a film of minerals and whatever else was in the water on the shaft of the manual release lever. Try working it multiple times before you heat up the water, this might loosen it up a bit, and add a drop or two of some type of penetrating oil, WD40 might work , then work it a bunch of times with the lubricant. A final tap on the end to seat it and you might be in business. If it keeps opening you might have the problem I did on an old heater, the thermostat would not control once in a while and the water would overheat to scalding temp. Try turning down the thermostat to 120 degrees. Over temp = over pressure.