Air Pressure Test for Water System (Failed at Water Heater Over Pressurization Valve)

[Kaajot]

Hi all-

So, I've patched up two pex tubes to the shower that had become disconnected and broken with new hardware, so my next test was to pressurize the water system with an air compressor and see if it would hold 30-40 psi.

Well, I'm attaching first the contraption I built to plug my pancake compressor into. It's probably not perfect and could have used some plumbers tape around the threads, but it did a decent job pushing air into the system.

http://www.sunlineclub.com/forums/at...3&d=1558111367

Here is the "Contraption" hooked up to the RV Water Service Hook-Up.
http://www.sunlineclub.com/forums/at...1&d=1558112117


Anyway, I pressurized and had water come out at the Water Heater. Here's a movie showing the first result (quick 18 seconds).

Here's a second video showing the same result, in action during the test, plus a dog helping at the end with the water drops.

And finally, a third video showing my test running the hot water heater and it appears to ignite just fine and ran for a few minutes with no issues. Also, more dogs, chickens, and off-grid stuff at the end.

All photos and video of this process are located at this google drive link.

Initial thoughts: Either the Hot Water Heater is ruptured internally around the Over pressurization Relief Valve OR I need to install a new Over pressurization Relief Valve and seal? I'm not 100% certain, but the water coming from BEHIND the relief valve's orifice at the point it should "connect" to the hot water heater has me very worried the water tank is cracked.

What's the best way forward here? I cannot check for any other leaks at this time because the hot water heater is losing massive amounts of air (and would have been water, glad we checked this).

[ggrvguy]

I guess I would unscrew the pressure relief valve first and make sure it's not split. But it sure looks to me like your tank is cracked somewhere around that outlet. Those aluminum tanks split open pretty easily if they are left with water in them over the winter.

Gary G

[Kaajot]

Originally Posted by ggrvguy

I guess I would unscrew the pressure relief valve first and make sure it's not split. But it sure looks to me like your tank is cracked somewhere around that outlet. Those aluminum tanks split open pretty easily if they are left with water in them over the winter.

Gary G

Yeah, that's what I'm worried. I thought the water was out (new to RV ownership 4 years ago, not as handy at that time too). But I'm guessing that nut on the left side opens the tank and dumps water out at the water heater?

Do I need to disassemble a lot of stuff to get the pressure relief valve? LIke, the whole system?

IF the tank is cracked, do they make replacement tanks or do I have to buy an entire new water heater system? If it's aluminum, can I patch it with rivets and solder? I don't think I can tig weld aluminum?

[mainah]

The heater tank valve is both thermal and pressure if the tank is not full the air space at the top of the tank maybe be too much for the valve. Generally the tanks rot out on the bottoms seldom at the top. If it froze there would be a big leak. I made the mistake once buying a tank for just a bit more money I could have bought the entire heater it wasn't much like maybe $20. The heater comes with everything brand new.

[Kaajot]

Originally Posted by mainah

The heater tank valve is both thermal and pressure if the tank is not full the air space at the top of the tank maybe be too much for the valve. Generally the tanks rot out on the bottoms seldom at the top. If it froze there would be a big leak. I made the mistake once buying a tank for just a bit more money I could have bought the entire heater it wasn't much like maybe $20. The heater comes with everything brand new.

So, I've got a new tank price around $140-$180 from various online sources and then I'd just have to retrofit all the components (and maybe a new pressure relief valve) into the tank.

So, do I disassemble it? Did you see the second video where I showed the water coming out? It was about 20 psi blown in and just produced a leak but it looks like the water is coming from behind the pressure relief valve's mounting point, ie either it's not tight or it cracked or its seal just wore out?

Given it's a 2001 Sunline, it would be probably an 18+ year old tank and may just be a smart idea to replace it and scrap the old one, but the furnace lights up and was throwing plenty of heat for the water heater, so all the parts SHOULD be good besides the leaking pressure relief valve/seal and the water heater tank itself.

[JohnB]

Hi KJ,

You are correct, the plug in the lower left is the drain plug for the water heater. To drain the heater, pull that plug and let it drain out until it stops. Also as fyi., that plug looks like a metal plug the prior owner put in it. Ideally that plug is a nylon one rated to potable water and the right temperature. They sell an Atwood (now Dometic) 2 plug kit of them on Amazon. Reason is, the tank is aluminum and the metal plug can easily cross thread the tank and create long term issues. The nylon plug, it is cross threads, the plug is toast but the tank is good. Getting that plug in and out for the times it needs to be drained, sooner or later in that location, it will cross thread.

Now to your leak. It does appear to be a crack of sorts in the tank. You can unscrew the safety relief valve (that is what it is called) and have a look at the threads etc. of the tank. Odds are high when the valve comes out, the valve may be damaged getting it out, so a new valve would be needed.

To get a wrench in there, it helps to take the sheet metal gas exhaust shield off. It allows more room for the wrench to turn. Those valves can be corroded in pretty good, especially if the prior installer did not use enough teflon etc to coat the threads good to help not corrode the valve to the tank. Being that hard to get it out, the valve can crush sometimes.

Here are a few pics. The gas tube exhaust shield is removed.


You can see the silver of the tank under the brass valve and what looks like white pipe thread sealant. The black sheet metal is just a cover and not the actual tank.

This one was stuck in pretty good, but it came out and the tank was OK. The valve was not reusable but is was leaking bad so that was why it was changed. This friend of mine has real hard water where he uses the camper.


Here is the old next to the new. As mainah said, these are both temperature and pressure relief valves. Pressure is 150psi max, the temperature I cannot recall exactly. I think around 190F. I can check if you need it.


They make these in 1/2" NPT and 3/4"NPT. Make sure you get the right one. This 2007 Sunline had a 3/4" NPT, the 2006 Sunlines and older many had 1/2" NPT. Atwood must of upsized it in the late 2006/2007 time frame


The valve you have in yours looked like a Cash Acme inplace of a Watts. Both brands are good but make sure it has the temperature relief feature.

Do you get a new tank or a whole new heater? Think through this decision. How many years into the future do you want to use the heater? If it is 18 years old now, how many years do you think the rest will be OK? If you are only going to use it a year or so and then sell the camper, then a tank only would be a something to consider. If you want to use it 5 plus years, that is more towards replacing it. But just a tank and safety relief valve will get you started. Your choice.

It will be the same work to pull out the water heater to replace the tank as it will to put a whole new heater.

To pull the heater out,

You need to unhook the piping on the back of the heater and the wiring inside on the back first. Then the gas line outside and tape the end of the gas line to dirt and bugs do not get in.

Take all those screws out around the outside flange face. You may need a heat gun to warm up the old putty around the flange to siding take to have it release from the siding. Then just pull the entire heater back out of the camper. There will be a wiring harness with wire nuts on it as you pull the heater out of the camper. You will have to stop and unhook the wires. Take a picture of the wire colors of that wire harness so you know how to hook it back up. Sunlines colors and Atwood colors are not all the same.

Then on the bench you can take the heater apart if you are changing the tank only.

Hope this helps

John

PS, do not run the heater very long with no water in it. A test fire on gas with no water for a few seconds is OK, but not minutes. And do not test it at all on electric with no water in it. If yours has the electric element. They burn out in seconds with no water in it. And if you have one, you will need to move the element to the new tank if you are not getting a whole new heater. The old element may not like coming out of the tank. They are in the inside back side of the tank if you have one.

[mainah]

Originally Posted by Kaajot

So, I've got a new tank price around $140-$180 from various online sources and then I'd just have to retrofit all the components (and maybe a new pressure relief valve) into the tank.

So, do I disassemble it? Did you see the second video where I showed the water coming out? It was about 20 psi blown in and just produced a leak but it looks like the water is coming from behind the pressure relief valve's mounting point, ie either it's not tight or it cracked or its seal just wore out?

Given it's a 2001 Sunline, it would be probably an 18+ year old tank and may just be a smart idea to replace it and scrap the old one, but the furnace lights up and was throwing plenty of heat for the water heater, so all the parts SHOULD be good besides the leaking pressure relief valve/seal and the water heater tank itself.

Furnace has nothing to do with the water system they are separate systems. If the water heater fires that's a good thing but I would still price the entire heater the price it not much different if indeed there is a crack in the tank. The tank is not a lot of fun to replace and the entire assembly has to come out to do it. I don't remember what heater it was but it required a special tool to remove/replace the ring holding the tank to the heater framework. I kind of doubt the tank is cracked at the top. The valve is a 1/2" tapered pipe thread it is exactly the same as one in the house except it is 1/2" instead of 3/4" What I would do is retry your test this time with water hooked up to the house turn on the water then open the pressure valve by lifting the small lever until water comes out close it and recheck the valve fitting.

[Kaajot]

Originally Posted by mainah

Furnace has nothing to do with the water system they are separate systems. If the water heater fires that's a good thing but I would still price the entire heater the price it not much different if indeed there is a crack in the tank. The tank is not a lot of fun to replace and the entire assembly has to come out to do it. I don't remember what heater it was but it required a special tool to remove/replace the ring holding the tank to the heater framework. I kind of doubt the tank is cracked at the top. The valve is a 1/2" tapered pipe thread it is exactly the same as one in the house except it is 1/2" instead of 3/4" What I would do is retry your test this time with water hooked up to the house turn on the water then open the pressure valve by lifting the small lever until water comes out close it and recheck the valve fitting.

The water heater (a furnace for water) does have something to do with it. I might have misstyped, but I thought it was clear from everything I'm doing that I was concerned with leak checks, water heater (furnace-type firing) checks as it's propane-heated, and water pump. In this initial test I determined the water heater fires but has a huge leak around the relief and temperature valve (per video).

Apologies if it confused you! I'll try to be better with nomenclature.

You don't think the tank is cracked? Did you watch the video where I was pressurizing it with air? I have left water in the heater in northern New York (because I relied on "smarter people than me" to tell me the water was out of the camper when winter hit -- they are not smarter than me, btw). So the short of the long is after pressurizing it and seeing water blow out from behind the valve, I most certainly left water in the tank for Winters 2015 through 2018. I'll crack it open later this weekend and film it to show how much water comes out. I'll also follow John's advice about taking the water heater heat shield off and trying to remove the valve to get a better inspection of the area, will post what that looks like once it's off!

[Kaajot]

Originally Posted by JohnB

The valve you have in yours looked like a Cash Acme inplace of a Watts. Both brands are good but make sure it has the temperature relief feature.

Do you get a new tank or a whole new heater? Think through this decision. How many years into the future do you want to use the heater? If it is 18 years old now, how many years do you think the rest will be OK? If you are only going to use it a year or so and then sell the camper, then a tank only would be a something to consider. If you want to use it 5 plus years, that is more towards replacing it. But just a tank and safety relief valve will get you started. Your choice.

It will be the same work to pull out the water heater to replace the tank as it will to put a whole new heater.

Hey John-

Well, the heater fired up when I did that quick test, so I'm pretty happy with that. I "think" the tank is cracked, will confirm soonest so I can make a decision on what to order, but I do plan on using the camper for many years to come.

I also have to say that a new tank with Styrofoam is about $190 cheaper than a new water heater unit. I found a great deal at this link, with new Styrofoam.

https://pantherrvproducts.com/dometi...kaAvxIEALw_wcB

I believe I'll want to replace the pressure and temperature relief valve, no matter what, on the new tank and go from there. If the new tank does not come with a nylon plug for emptying then I'll need to get one of those like you said as well. Yep, doesn't come with one per review of the pictures in the link. So two things to add to it in order to "rebuild" the whole system.

Attaching a picture of the Model/Serial ID to confirm a 91412 Hot Water Heater Inner Tank is the correct replacement tank for this furnace, GC6AA-9E.

Model/Serial of Hot Water Heater with potential cracked tank near safety pressure & temp relief valve.

Also attaching a picture labeled ThingMaBob, it's a drain downspout to the left of the water heater, below the "shower/hose" extension on that side of the camper. I tried "opening" and cracked the turn-dial top (very brittle). Is this an overflow valve, and can I find one to replace/change it out?

ThingMaBob Google Drive Picture.

For the nylon plugs, I found a Nylon Plug Kit on Amazon for about $11, Part # 11633 for the plug. Is that the correct one?

Here's the link to the Nylon Plug Kit on Amazon.


Also, would a Camco Pressure and Temperature Relief Safety Valve work? I found a decent one (rated 150 psi, 210 F temp) at Amazon and walmart for $10.99. I'll measure before I order, but guessing I am a 1/2" (they have a 3/4" too).

Here's the link for Camco Pressure and Temperature Relief Valve at Amazon.

I think that covers all my questions, now I just need to get some measurements and a deeper inspection at the safety valve to see if it is indeed a tank crack or loose threads and worn teflon/plumber tape/adhesive. I didn't try hand-spinning it, will see if it moves freely tonight when I'm out taking care of the doggers.

Best.

-KJ

PS: Thanks also for inputs, mainah! I really think the darn tank is cracked -- it's just very odd to be leaking the way it is when only 20-40 psi is pushed through with a pancake air compressor.

[Kaajot]

Hi All-

Update from an Inspection.

I checked it out, the tank is indeed cracked where the water was running out. Going to buy a new tank once I can confirm I have the right part number, but it looks like it.

Secondary question, should I reuse this Safety Valve? I'm thinking no -- attaching pictures. It has a bit of corrosion on the inside, could clean out, but it's $10 for a new one.

Third, it appears the drain plug, also in a picture, is a 3/4" on OD threads and maybe 5/8" ID, so is it a 1/2" or 3/4"? I always get confused about this, but Safety Valve says it's a Cash-ACME 1/2NCLX-5, so I'm inclined to believe that means it's a 1/2 inch and both my drain and safety valve are 1/2".

Also, one video to watch linked here -- emptied out at least 3-4 gallons of water, so yep, it was full or darn near full.

Inspection Photo/Video Dump right here.

PS: I was able to get both things off with an adjustable 45 deg neck wrench. It helped that they did use Teflon on install, so even with rust apparent at the crack and inside the cap there was not too much binding resistance.

[krazedave]

Just a thought about just buying and installing a new tank or whole new water heater. I noticed you have black potted board, upper right, when that fails your are looking at over 100.00 for a replacement. For the age of your trailer I am surprised that it has not be replaced by now.

[Kaajot]

Originally Posted by krazedave

Just a thought about just buying and installing a new tank or whole new water heater. I noticed you have black potted board, upper right, when that fails your are looking at over 100.00 for a replacement. For the age of your trailer I am surprised that it has not be replaced by now.

NO kidding? What exactly is black potted board, the electronic board?

I saw some tune-up kits that sold things like new boards, etc. It seemed pretty easy to manage and retrofit. Is $100 just the part, or is that if someone else (RV Repair Shop) does it?

I called our local RV Shop and they kind of rubbed me the wrong way, saying their #1 priority was "their customers," ie the people they sold new rigs to. So they kind of lost me at that point, particularly because I can do mechanical, electrical, and machining work. Customer service is demeanor more than anything and they just didn't have it.

[Kaajot]

I just found this, researching black potted board. $75 after Shipping and Handling for my water heater. If this is the item, I'm ok with another $75 in the future. That's under $275 to keep the entire water heater system rolling.

I think I'm a little committed at this point -- received a notification from Amazon that my new water heater tank has shipped as of 2 minutes ago. *_* I was waiting for more inputs, but saw it's still $200 cheaper than a brand new one and hoping I get a few more years before I need to change out the circuit board. May buy a spare and keep it in the camper later this Summer if funds are not tight just to be ready.

[johnnybgood]

Your “thingamabob” is the drain for your fresh water holding tank.

[Kaajot]

Originally Posted by johnnybgood

Your “thingamabob” is the drain for your fresh water holding tank.

That's what I thought. Thanks!

Got a good part number?

[johnnybgood]

https://www.amazon.com/Valterra-A01-...ater+ta&sr=8-7

[mainah]

Guess the only tanks I have seen here in Maine that were cracked were pretty catastrophic they don't like to be frozen and splits them open enough to see inside. Yeah they have gone up a bit on price so a tank is $100 less then a complete unit the last one I bought was like $30 difference for the effort it was far more attractive. I still have got to wonder why it's cracked at the fitting a gorilla with a pipe wrench on the fitting?

[Kaajot]

Originally Posted by mainah

Guess the only tanks I have seen here in Maine that were cracked were pretty catastrophic they don't like to be frozen and splits them open enough to see inside. Yeah they have gone up a bit on price so a tank is $100 less then a complete unit the last one I bought was like $30 difference for the effort it was far more attractive. I still have got to wonder why it's cracked at the fitting a gorilla with a pipe wrench on the fitting?

Well, I recall the previous owner demonstrating the water for me and having some issues with the water system including the pex piping falling apart (breaking) above the Power Center and shorting out everything. There's a chance the hot water heater was also cracked long ago because I remember some water dripping and was brand new to campers.

However, we may have somehow emptied the hot water heater to 3-4 gallons, so it was not completely full and possibly held up against the ice expansion. There's a chance we did put some antifreeze that made it to the hot water heater. I'm not sure, but I don't think it was 100% full. Or I got very lucky and it cracked a little and then emptied out some of its water and held onto the rest. There is significant rust showing on the crack, so it's an old crack.

Yeah, I'll go $200 vs $400 for this and if I have to replace the control board, another $75 - $125 (if I make a dino robotics upgrade, do they make the control board via DR?) will keep the new deal humming along later. It was $176 for the tank, $10 for a new safety valve, $10 for a new set of plugs with the tool. Calling it $200.

Will document when I start tearing this apart in a week or so.

[JohnB]

Originally Posted by Kaajot

I believe I'll want to replace the pressure and temperature relief valve, no matter what, on the new tank and go from there. If the new tank does not come with a nylon plug for emptying then I'll need to get one of those like you said as well. Yep, doesn't come with one per review of the pictures in the link. So two things to add to it in order to "rebuild" the whole system.

Attaching a picture of the Model/Serial ID to confirm a 91412 Hot Water Heater Inner Tank is the correct replacement tank for this furnace, GC6AA-9E.

Model/Serial of Hot Water Heater with potential cracked tank near safety pressure & temp relief valve.

Also attaching a picture labeled ThingMaBob, it's a drain downspout to the left of the water heater, below the "shower/hose" extension on that side of the camper. I tried "opening" and cracked the turn-dial top (very brittle). Is this an overflow valve, and can I find one to replace/change it out?

ThingMaBob Google Drive Picture.

For the nylon plugs, I found a Nylon Plug Kit on Amazon for about $11, Part # 11633 for the plug. Is that the correct one?

Here's the link to the Nylon Plug Kit on Amazon.


Also, would a Camco Pressure and Temperature Relief Safety Valve work? I found a decent one (rated 150 psi, 210 F temp) at Amazon and walmart for $10.99. I'll measure before I order, but guessing I am a 1/2" (they have a 3/4" too).

Here's the link for Camco Pressure and Temperature Relief Valve at Amazon.

I see you went hunting and found some issues.

Yes, hands down replace the temperature & pressure relief valve. The camco one you like, this one T&P Valve 1/2"

It has the right NPT ports, the correct temp and pressure setpoints and the correct probe length. But I cannot find a BTU rating on it. Even on the Camco site. The Watts brand lists it can release 15,000 btu's. If you get it. look on the tag on top. It should call it out.

This is the Atwood one for it, their PN 91604 1/2" NPT . I'm sure Atwood does not make them, but it is carded as their part number and spec. https://www.amazon.com/Atwood-91604-...r=8-1-fkmrnull

The Nylon plugs, Atwood number 91857. See here. I use these folks too from time to time. They are cheaper sometimes then Amazon. Shipping is free over $99 but these plugs come USPS so the shiping is not much https://www.rvupgradestore.com/Atwoo...-p/42-0148.htm

[JohnB]

You are going to need some butyl sealing tape when you install the heater back in the camper. Look for 1" wide, 1/8" thick. You have to clean the siding and the back flange of the water heater very clean. When get all the goo off, do a final clean with a high flash cleaner, even isoproal alcohol if that is all you have, to get any oil reduce off the camper siding and flange. Make sure it is good and dry from the cleaner before putting the new butyl tape on. Do not use Acetone and it will strip the paint off the camper.

I know these high flash cleaners work and do not take the paint off the camper.
isoproal alcohol
Eternaclean
Naphtha (my main go to high flash cleaner.)
PPG DX 330 (very expensive)
Denatured Alcohol (this is not rated as a cleaner, but many use it.
Lacquer thinner

I'm sure there are more, test on a small area first to look for ill effects

Hope this helps

John