Atwood water heater blowing fuse?

[GraySeal65]

Gas only Atwood water heater was working fine, turned the switch on the other day and it popped the fuse. I wiggled the wires and it ran for a day and popped the fuse on the way home. Any one have a similar problem?

[nothermark]

Have not had one on an Atwood but have done it several times on a home hot water tank. Some water eats the element tube allowing leakage and several failure modes.

[GraySeal65]

Fixed, The temp cut off switch is held in by a lock ring that you push in and turn, it came loose and the spade terminal on the one side of the switch was touching the body of the heater.

[nothermark]

Thanks for telling us! Another gotcha to keep in mind. ;-)

[KenMerk]

I have an Atwood G6A-8E water heater, and had the circuit board replaced a month ago. Shortly after, the 2 amp fuse on the board burns out every 4-6 days and I have to replace it. Any thoughts?

[mel s]

Originally Posted by KenMerk

I have an Atwood G6A-8E water heater, and had the circuit board replaced a month ago. Shortly after, the 2 amp fuse on the board burns out every 4-6 days and I have to replace it. Any thoughts?

KenMerk
Are you sure the fuse is supposed to be only a 2 amp fuse?
My replacement Dinosaur board uses a 5 amp fuse.

Mel
'96 Safari

[Mr_Fixit]

Since that problem is really unusual, can you tell me why the first board was replaced? Any anomalies in any other 12-volt system? All connections are good at the heater on the outside?

Steve

[Mr_Fixit]

You can not compare the fuse size on a Dinosaur. The fuse on the factory board is a 2 amp.

[KenMerk]

Originally Posted by Mr_Fixit

Since that problem is really unusual, can you tell me why the first board was replaced? Any anomalies in any other 12-volt system? All connections are good at the heater on the outside?

Steve

Steve,
The heater stopped igniting. I went to an RV repair shop and the service manager said it "sounds like the circuit board quit on you". I brought the MH in and he replaced the board. It worked, until I was 200 miles away, then it quit and I found the fuse had burnt. I called him then, he had no clue, told me to call Atwood; i did and waited on hold 20 minutes before leaving a message. I received there message the next day, saying they could maybe help me troubleshoot if I could connect the heater to a separate 12 volt battery. All other 12 volt systems are without aberration. Connections are solid.

[Mr_Fixit]

Okay, the first thing you want to do is very simple. Unplug your shoreline and run the water heater so you are using just battery power on your rig. Amp draw through the water heater is very low, so a fully charged battery will have no problem keeping up with the demand. That will remove any possiblity you are dealing with a converter that is starting to fail. Probably not, but let's eliminate that first. That is why Atwood suggested it.

The first rule in troubleshooting an appliance that relies on 12 VDC power is to use another known good 12-volt power source. Your symptoms would, in my experience, be unusual for a board failure (which is normally all or none and continuous).

The task now is to figure out why the fuse is blowing. What is increasing amp draw through the board? Could be a new board out of the box is bad. I have had it happen, but rarely. It does not sound like the new board improved things.

Do you have a multimeter and are you familiar with it's use?

Steve

[mel s]

Originally Posted by Mr_Fixit

Since that problem is really unusual, can you tell me why the first board was replaced? Any anomalies in any other 12-volt system? All connections are good at the heater on the outside?
Steve

Many RV dealers and mobile RV techs have a "control board tester".
Most will test water heater, (or furnace, or refrigerator), boards at no charge... if you remove the board and take it to them.

Mr_Fixit
If your question is addressed to me? the answer is:
I replaced my WH control board with a new Dinosaur board last year because my then 18 year old Suberban SW10D propane only WH would no longer fire every time I wanted it to... (the board tested bad at a dealers shop).

https://www.youtube.com/watch?v=gRBmlIJCehY

Mel
'96 Safari, 145k miles

[Mr_Fixit]

No, I was not referring to the Dinosaur replacement, but it was surely a good choice. I like the boards and like the folks at the factory. Dinosaur makes a great board don't they?

You are absolutely right about using a Fenwal (brand) tester on the board. I was assuming the OP did not want to go back to a dealer until he tried some things himself.

The single thought I have about the tester is, if the water heater is working for up to 4 hours at a time, the component that is failing must be on the front end of failure and I am not sure the tester will pick it up. It picks up ignition and gas valve operation and we know the water heater is doing those things. It is certainly worth a try having it tested, if convenient, and that is an excellent suggestion.

Steve

[mel s]

Originally Posted by Mr_Fixit

No, I was not referring to the Dinosaur replacement, but it was surely a good choice. I like the boards and like the folks at the factory. Dinosaur makes a great board don't they?

You are absolutely right about using a Fenwal (brand) tester on the board. I was assuming the OP did not want to go back to a dealer until he tried some things himself.
The single thought I have about the tester is, if the water heater is working for up to 4 hours at a time, the component that is failing must be on the front end of failure and I am not sure the tester will pick it up. It picks up ignition and gas valve operation and we know the water heater is doing those things. It is certainly worth a try having it tested, if convenient, and that is an excellent suggestion.
Steve

Because my WH problem was intermittent it was difficult to replicate. Repeated bench tests of my board where necessary to determine that my board was bad.
(Fortunately the shop did not charge me for the repeated testing).
Mel
'96 Safari

[Mr_Fixit]

I have two board testers, but seldom use them as, if the board is bad, it is obvious, and if it is intermittent, you have to catch the problem at just the right time. As the factory is fond of saying, "just because the tester says it is good, does not mean the board is good", which was your situation.

I wish this stuff was as cut and dry and folks often think.

Steve