Water heater keeps blowing fuses!

[ezzywave]

Hello everyone, new guy here.

I have a 2019 FR Salem toyhauler. The water heater worked normally until last weekend. Propane only heater. When I hit the water heater switch it immediately blows the fuse. I have tried unplugging everything under the outside cover and it still blows the (new) fuse. Then I unplugged the on/off switch and manually connected the wire ends, same result.

I must have a short to ground somewhere. Is this a common problem? If so, where does the short usually occur?

Any advice is appreciated. Trailer is still under warranty, but the dealers are backed up a month or more.

[bikendan]

Since you are new, you may not know that you can use an independent RV shop or mobile RV technician for warranty work. You just have to get pre-approval from FR and be willing to be reimbursed.
One question, how can a 2019 still be under warranty, since FR only offers 1 year factory warranty?

[Thomas ho]

under the rubber cover top of water heater left side front, are buttons , to reset water heater. remove cover left side of each switch is a small wire running top to bottom. if missing/ burnt away, replace 15.00$ . 1 is 12v 1 is 115v. then buy a element socket @ hardware store pull element , look for blistering , off color as in hot cold spots. replace if not good. need more help GOOGLE IT / UTUBE. suburban water heater.

[5picker]

Originally Posted by Thomas ho

under the rubber cover top of water heater left side front, are buttons , to reset water heater. remove cover left side of each switch is a small wire running top to bottom. if missing/ burnt away, replace 15.00$ . 1 is 12v 1 is 115v. then buy a element socket @ hardware store pull element , look for blistering , off color as in hot cold spots. replace if not good. need more help GOOGLE IT / UTUBE. suburban water heater.

Thomas... Thomas... the OP says it is a PROPANE ONLY water heater!

To the OP... you are going to need to do some wire tracing. Check the feed from the fuse panel to the switch. (with switch disconnected) Does it still blow the fuse? If so the problem is between the fuse panel and the switch. If not, since you mentioned eliminating the switch and disconnecting everything outside at the water heater (did you unplug the control board?) then the issue is in the wiring from the switch to the water heater.

It could be anywhere along that path. You'll need to trace the wiring somehow.

[wmtire]

Originally Posted by ezzywave

Hello everyone, new guy here.

I have a 2019 FR Salem toyhauler. The water heater worked normally until last weekend. Propane only heater. When I hit the water heater switch it immediately blows the fuse. I have tried unplugging everything under the outside cover and it still blows the (new) fuse. Then I unplugged the on/off switch and manually connected the wire ends, same result.

I must have a short to ground somewhere. Is this a common problem? If so, where does the short usually occur?

Any advice is appreciated. Trailer is still under warranty, but the dealers are backed up a month or more.

Couple questions about what is emboldened in red above just to be absolute sure of something. You say it's propane only water heater. What/where is this switch you are referring to?

[ezzywave]

Bikendan --- Wife made me buy an extended warranty.

wmtire --- The on/off switch located in the trailer. The pump switch is to it's left and a tank heater switch to it's right. Above the switch are the lights to show how full the tanks are.

--- Ahhhhhh... control board? I really hate to ask this, where would I find it?

[aceinspp]

I'm curious also as is this a propane only heater i'm guessing its both electric and gas. You may have burnt out the electric heating element which will cause unit to short out and trip fuse. Later RJD

[ezzywave]

propane only

[wmtire]

OK, I have pointed out some things in your pic. I recall you saying you have disconnected much stuff, and this may be from that.


The red arrow is pointing to your electrode assembly (it makes sparks to ignite the propane). Usually the black boot covers this electrode more so than yours is in the pic. Can you pull the boot back a little and make sure the spade connector is firmly on the electrode. This spade connector will be on the end of the orange-ish wire I also have a red line going to.


Can you also make sure this orange-ish wire, where it comes out from behind the water heater, is not frayed or bare and possibly shorting out on the water heater metal?



Now on the left hand side, where I have the other red line. Can you make sure this brown wire is not frayed by the gas solenoid. It may just be the angle, but it almost looks like the wire is crushed.

[ezzywave]

wmtire--- I closely examined the wires you pointed to and can see no damage to them.


I did find the controller on the back of the hot water tank. I unplugged the controller, then (using a multimeter) measured the resistance between the end of the power wire (that goes to the controller) and ground. Zero ohms. The wire is colored the same as the wire that comes from the water heater power switch on the wall panel.

Apparently I have a short between the water heater switch and the water heater controller.

BTW, why is it called a hot water heater? It's a cold water heater!!!

[Larry-NC]

Originally Posted by ezzywave

wmtire--- I closely examined the wires you pointed to and can see no damage to them.


I did find the controller on the back of the hot water tank. I unplugged the controller, then (using a multimeter) measured the resistance between the end of the power wire (that goes to the controller) and ground. Zero ohms. The wire is colored the same as the wire that comes from the water heater power switch on the wall panel.

Apparently I have a short between the water heater switch and the water heater controller.

I agree. It sounds like a shorted control board. When you remove it, see if there is a burned spot on the back side. There was a bad lot a couple of years ago and they all failed that way. If that's what you've found, call Suburban (the manufacturer) directly and they will probably send you the board for free, for you to self-install.

More work than the warranty, but gets you back on the road quicker.

[nomad297]

Originally Posted by ezzywave

BTW, why is it called a hot water heater? It's a cold water heater!!!

Technically, it is a water heater, but hot water is defined as water that is 110 degrees in the plumbing world. So, since most of these water heaters have a cutoff high temp of ~130 degrees, they can become a hot water heater once they begin heating the 110 degree water to more than 110 degrees. They are a water heater at first, then they become a hot water heater.

Bruce

[5picker]

Originally Posted by ezzywave

wmtire--- I closely examined the wires you pointed to and can see no damage to them.


I did find the controller on the back of the hot water tank. I unplugged the controller, then (using a multimeter) measured the resistance between the end of the power wire (that goes to the controller) and ground. Zero ohms. The wire is colored the same as the wire that comes from the water heater power switch on the wall panel.

Apparently I have a short between the water heater switch and the water heater controller.

BTW, why is it called a hot water heater? It's a cold water heater!!!

It shouldn't be.

Manufacturers don't call them that.
Experienced trade people don't either.

Water, (in its liquid form) regardless of temperature is.... water!
So no matter at what temperature you begin to raise water temperature. you are simply heating water.

Those that call them hot water heaters are incorrect.

ON EDIT: I got so zoned in on the hot water heater comment, I forgot to comment on your diagnosis.... I don't believe you have a short in the wiring. (your test explanation is confusing to me). Like Larry, I'd bet you have a bad control board.
Put in a new fuse, connect the wiring back to the switch as it was and leave the board unplugged. Turn on the switch and see if the fuse blows. I'd bet it doesn't.

[mac1_131]

Originally Posted by ezzywave

wmtire--- I closely examined the wires you pointed to and can see no damage to them.





I did find the controller on the back of the hot water tank. I unplugged the controller, then (using a multimeter) measured the resistance between the end of the power wire (that goes to the controller) and ground. Zero ohms. The wire is colored the same as the wire that comes from the water heater power switch on the wall panel.



Apparently I have a short between the water heater switch and the water heater controller.



BTW, why is it called a hot water heater? It's a cold water heater!!!

Sounds like your wire is pinched somewhere between the switch and where it attaches to the control board. I guess the good news is the water heater itself is probably ok.

[Larry-NC]

Originally Posted by mac1_131

Sounds like your wire is pinched somewhere between the switch and where it attaches to the control board. I guess the good news is the water heater itself is probably ok.

Why did you guess that?

The OP, ezzywave, stated that he had removed the control board and measured its terminals from +12 to ground and got zero ohms (dead short). That points pretty well to the control board as the failure point.

I suppose he could put in a fuse while the control board is removed, to prove that there's not a pinched wire or other short, but the likelihood of TWO short circuits on the same path is pretty small.

Read this again and see if you don't agree.

[mac1_131]

Originally Posted by Larry-NC

Why did you guess that?



The OP, ezzywave, stated that he had removed the control board and measured its terminals from +12 to ground and got zero ohms (dead short). That points pretty well to the control board as the failure point.



I suppose he could put in a fuse while the control board is removed, to prove that there's not a pinched wire or other short, but the likelihood of TWO short circuits on the same path is pretty small.



Read this again and see if you don't agree.

He said he measured from the end of the wire he disconnected towards the switch. No guessing involved. Thank you for your concern.

[Larry-NC]

Originally Posted by mac1_131

He said he measured from the end of the wire he disconnected towards the switch. No guessing involved. Thank you for your concern.

Ahh. I understood he was measuring across the terminals of the disconnected board--because that's what I might have done. I shouldn't try to respond when I'm rushing.

It's likely to be a short in the hot lead anywhere back to the fuse panel. If you look at the schematic, the hot lead goes through both the Hi-Limit switch and Thermostat first, before it gets to the board. See https://www.rvupgradestore.com/v/vsp...stallation.pdf , page 7.

They are both behind a big rubber plug at the top (outside) of the unit which covers both the limit switch and thermostat. If there's nothing obvious when inspecting, the OP should disconnect them and see if the short is still present.

[5picker]

Originally Posted by Larry-NC

Ahh. I understood he was measuring across the terminals of the disconnected board--because that's what I might have done. I shouldn't try to respond when I'm rushing.

It's likely to be a short in the hot lead anywhere back to the fuse panel. If you look at the schematic, the hot lead goes through both the Hi-Limit switch and Thermostat first, before it gets to the board. See https://www.rvupgradestore.com/v/vsp...stallation.pdf , page 7.

They are both behind a big rubber plug at the top (outside) of the unit which covers both the limit switch and thermostat. If there's nothing obvious when inspecting, the OP should disconnect them and see if the short is still present.

I usually don't have much problem following along but I guess I'm still confused as to what the OP actually tested with the meter? The wire?

[Larry-NC]

Originally Posted by 5picker

I usually don't have much problem following along but I guess I'm still confused as to what the OP actually tested with the meter? The wire?

After re-reading his post, I concluded that he pulled the hot and ground wires from the control board terminals and measured across the two wires. (At first I thought he measured across the board terminals.)

That likely exonerates the control board but is otherwise not very diagnostic. Within the water heater it could be the Hi-limit switch or thermostat or the wires connecting them, or it could be 12v wiring all the way back to the distribution board or it could be other appliances on that same fuse circuit, if any.

Since the OP said post #1) that when he disconnected the interior switch, the fuse didn't blow.

That isolates the fault to the segment from the switch, to the heater, and through the Hi-Limit and Thermostat and on to the wiring leading up to the control board. Next step is to break this segment down. The schematic is very simple. See page 7 on the left.

Since the OP has already measured the wiring at the board terminals, he could make the same measurement with the thermostat or high-limit disconnected. That would indicate whether the shorted segment is between switch and thermostat/hi-limit, or between thermostat/hi-limit and control board.

[5picker]

Originally Posted by ezzywave

Hello everyone, new guy here.

I have a 2019 FR Salem toyhauler. The water heater worked normally until last weekend. Propane only heater. When I hit the water heater switch it immediately blows the fuse. I have tried unplugging everything under the outside cover and it still blows the (new) fuse. Then I unplugged the on/off switch and manually connected the wire ends, same result.

I must have a short to ground somewhere. Is this a common problem? If so, where does the short usually occur?

Any advice is appreciated. Trailer is still under warranty, but the dealers are backed up a month or more.

Originally Posted by Larry-NC

After re-reading his post, I concluded that he pulled the hot and ground wires from the control board terminals and measured across the two wires. (At first I thought he measured across the board terminals.)

That likely exonerates the control board but is otherwise not very diagnostic. Within the water heater it could be the Hi-limit switch or thermostat or the wires connecting them, or it could be 12v wiring all the way back to the distribution board or it could be other appliances on that same fuse circuit, if any.

Since the OP said post #1) that when he disconnected the interior switch, the fuse didn't blow.

That isolates the fault to the segment from the switch, to the heater, and through the Hi-Limit and Thermostat and on to the wiring leading up to the control board. Next step is to break this segment down. The schematic is very simple. See page 7 on the left.

Since the OP has already measured the wiring at the board terminals, he could make the same measurement with the thermostat or high-limit disconnected. That would indicate whether the shorted segment is between switch and thermostat/hi-limit, or between thermostat/hi-limit and control board.

I thought the OP already did that but I guess I'm not sure any more.

Seems the OP has enough information to make tests on the wires, the board and anything within the water heater. Hopefully they can find the issue.