OT hot water heater

[ericlb]

i know a tractor forum has little to do with a water heater, but there are some professional plumbers here too, the problem is, while the water heater isn't very old, maybe 3 or 4 years, it has started coming on often, its propane, i have been under the house, and have no water leaks in the plumbing, also inspected in the house, under sinks washer ect nothing, turning the temperature selector way down doesn't make much difference, leading me to suspect that big silver box on the water heater is bad, how much of a chore is it to change that, and what is the proper name for the big silver box on the side of the water heater?

 

[old]

One question. Why heat hot water. Me I heat cold water so I have a water heater..

That said a heavy build up of lime in the bottom of the tank can cause that. If it was electric I would say the same thing or the lower element is burned out

 

[Russ from MN]

Is the water coming out hotter than you like? If not, maybe it's not a problem, or you could have a faucet bypassing internally and have thermosiphon circulation. There are a couple of ways to check for that, when you turn on a cold water faucet the water should not be warm, although there are some new systems to keep hot water at the faucet, and they circulate some hot water back into the cold water line. Have you changed a faucet lately? Are you sure you don't have a leak somewhere? Is the toilet hooked up to hot water? Some are to prevent condensation on the tank. Good luck! You are probably going to get some replies, Why would you need to heat hot water!!

 

[ericlb]

no i havent changed any faucets in awhile the last thing i did was replace a toilet probably 2 years ago, no warm water on any of the cold side of the sinks ect we also drained the water heater, very little calcium build up in the tank,

 

[GordoSD]

Me I is a double pronoun and poor grammar. Verbose. How does that go about glass houses?

 

[GordoSD]

Me I ?

 

[old]

How many times do I have to say leave me alone.

 

[Phil9N3667]

You tell him, Old!! My daughter teaches 8th grade English, so we get lots a corrections at our house!!

 

[Ozlander]

(quoted from post at 11:31:08 11/02/16) Me I ?

Should be Me, I

Everybody knows that.

 

[Steve@Advance]

One way to determine if there is a heat load on the heater is to feel the hot out pipe. When you know no hot water has been used for a few hours, pull the insulation back a couple feet from the tank, if the line is hot there is hot water going "somewhere". If it is cool or slightly warm, there is no leak.

If the temperature hasn't changed, the thermostat valve may have lost it's differential (or "dead band"), the difference in temperature from cut on to cut off. There is a few degrees difference so it won't rapid cycle off and on. I don't think it is adjustable, at least the old ones weren't, not sure what model you have. It probably will need a new thermostat valve to fix it if that is the problem.

 

[Janicholson]

I find your speech patterns quit acceptable. No issue with me. I teach communications at a university, and see much worse. I just put a period between the me, and I Jim

 

[ed will]

Stop fighting. Go on Tales. Ed Will

 

[docmirror]

First, I'm not a pro plumber. I do have a number of rentals which I maintain, and I've come up against this one before. Not a fan of throwing parts at stuff, but it sounds like you've diagnosed it fairly well if there's no thermo circulation going on in your plumbing from hot to cold side. You can also test this by turninf off the inlet from the cold side to the water heater and letting it sit for a few hours. These situations are common where you find a lot of single handle faucets where the water is mixed in the ball at the base handle. They can leak around.

Anyway, that silver thing is the gas control thermostat.

https://hdsupplysolutions.com/shop/p/rheem%C2%AE-propane-gas-water-heater-valve-p737841?gclid=CL6QrersitACFQuSaQodkxcLwg

The brass looking thing sticking out goes into the tank, and the whole assembly screws in with pipe threads on the back of the valve. The brass thing contains a temp sensor which will open and close the gas valve based on expansion of the fluid/gas inside the tube. There are fittings for the LP inlet line, and two or three terminal connections for the pilot thermocouple. Of course, it may be one of those pilotless types, in which case, you're beyond the scope of this discussion. Assuming it's not the pilotless type, there's a thermocouple down in the lower burner area which keeps the gas valve ready for operation, and provides the pilot for the burner to turn on when the gas valve is opened.

The sensing of the water temp is done inside that brass tube, and they do go bad sometimes. The temp setpoint dial adjusts the pin that operates against the expansion gate pin inside the brass tube to regulate the on and off of the heater. Since you've had no luck changing the temp setpoint, it possible that metering pin in the brass tube has gone haywire.

It's not a hard job to replace. Turn off the water pressure in the cold delivery side to the heater. Drain the tank below the level of the gas valve. Turn off the LP supply to the valve. Undo the LP fitting to the valve, and the fitting that goes down to the burner tray and disconnect the wires from the thermocouple. Now, the whole assembly will unscrew from the water heater, but you typically need a massive wrench on the body, or sometimes there is a square or six flat behind the valve body where you can get a large open end wrench in. I've also put a stub of pipe on the inlet, and use the stub as a 'wrench' to turn the whole valve. Remove the old valve, use some thread seal, and screw in the new valve, connect the thermocouple, LP lines, turn on the LP supply and check for leaks with soapy water around the LP inlet and outlet. Fill with water, check for leaks. Follow the manual to start the pilot, and turn it on. Once the pilot will stay on, turn on the gas supply on the valve and wait for the gas to kick on to the burner. Check again for LP leaks on the outlet side of the gas valve. Let it come up to temp, and then take a shower. See if it cycles like before, or if it's too fast again. If too fast cycle, you have a water circulation problem.

 

[GordoSD]

I, myself don't agree. It's pleonasm and redundant.
LOL

 

[tn terry t]

(reply to post at 16:18:55 11/02/16) pretty good article but a little out dated. there is no longer a American waterheater company. they were bought out by A.O. Smith not too long after this was written

 

[showcrop]

Significant increase in burn time would mean both a lot more water being heated and a lot more propane being used. Are you sure that your propane use has gone up? Another possibility, though uncommon, is a partially blocked burner, which would result in more burn time but no more water heated or propane burned.

 

[FBH44]

BE VERY CAREFUL!!!! Propane is both heavier than air, and it will deaden your smell. Working on that, in the basement / crawl space, you can release propane, it WILL collect in a thick invisible layer on the floor, you WILL NOT smell it, and when you go to relight..... KABOOOMMMMMM! I did that, and survived, but never again. Believe me on this one.

 

[Rons b]

I've had to replace my propane heater 2 in 15 years because on the calcium buildup in the bottom of the heater I didn't drain it often enough. I've since learned

 

[bwillett]

"Me" and "I", in Old's usage, needs a comma between the "Me" and the "I".
As in: Me, I try not to correct someone else's grammar or spelling because I am not as perfect as some on here seem to think they are.

 

[showcrop]

(quoted from post at 16:22:37 11/02/16) "Me" and "I", in Old's usage, needs a comma between the "Me" and the "I".
As in: Me, I try not to correct someone else's grammar or spelling because I am not as perfect as some on here seem to think they are.

Aw, come on, putting a comma in there doesn't make it correct to name the same subject twice.

 

[showcrop]

(quoted from post at 15:48:28 11/02/16) BE VERY CAREFUL!!!! Propane is both heavier than air, and it will deaden your smell. Working on that, in the basement / crawl space, you can release propane, it WILL collect in a thick invisible layer on the floor, you WILL NOT smell it, and when you go to relight..... KABOOOMMMMMM! I did that, and survived, but never again. Believe me on this one.

Yes, propane is heavier than air, and yes, per the instructions on every gas appliance made in the last thirty years you are warned to allow time for the gas to dissipate before attempting to relight the pilot, but where do you get this idea about it deadening your smell?

 

[Janicholson]

Fun. Jim

 

[Armand]

Just a quick question. I have a 40 gallon Rheem electric water heater. It is about 15 years old and works beautifully. Because of the age I wanted to change it out . A friend of mine is a plumber and he said the older ones had glass tanks and they rarely leak and it should last quite a while. When I drain the tank clear water comes out, no rust, and it works great. Only had to change the thermostat once, guess it was the minerals in the well water. Should I change it out? Any opinions?

 

[Dean Olson]

That big silver box is the gas control valve. Turn water & gas off and drain. Remove burner,pilot tube, and thermocouple. Valve unscrews. I use a 6" nipple in the gas opening as a "wrench". If it's only 3-4 years old it's likely under warranty. Is the gas control metal or plastic with a indicator light? If it the metal valve it's rare those fail. The plastic valve routinely fails.

Double check the T&P drain and make sure it's not leaking. If you sure you have no leaks and the Temperature and Pressure relief valve is holding, then it may be a failed gas valve.

I'd pressure test your water supply distribution system. Put a gauge on the water heater drain and shut the water off to the water heater. If the gauge holds your good. If not keep looking for a leak.

 

[Dean Olson]

If it's located in a place, such as the attics down here in Houston, where it will do property damage WHEN it leaks I recommend arbitrary
replacement every 10-12 years. The logic is that the 1-2% deductible on you HO ins is far more than the cost of new heater.

If it's located in the garage or basement next to a floor drain let it go till it fails. If it can't do any damage get the most value out of it you can. I
have seen some of the glass line tanks last 30 years.

 

[Armand]

(quoted from post at 20:33:47 11/04/16) If it's located in a place, such as the attics down here in Houston, where it will do property damage WHEN it leaks I recommend arbitrary
replacement every 10-12 years. The logic is that the 1-2% deductible on you HO ins is far more than the cost of new heater.

If it's located in the garage or basement next to a floor drain let it go till it fails. If it can't do any damage get the most value out of it you can. I
have seen some of the glass line tanks last 30 years.

Thanks Dean, I might as well replace it. It will cost just about what the deductible is.