Water heater problem

[Barryfish]

I have a 2008 four winds Thor C5500 Kodiak motorhome.
I changed my water heater control board to a dinosaur board about 6 months ago. It has been working since changing it. Well today I took a shower and didn't have much hot water. Checked the circuit breaker, it was flipped. Tried flipping it and it wouldn't go up. Went outside and checked to make sure the fuse on the board wasn't blown. Seen the yellow light on the dinosaur board that says ac relay. So I went back took the wire our of the circuit breaker and moved it to another breaker to eliminate the breaker just being broke. It popped that breaker too. Put the wire back to the original breaker and put the wire from the one I swapped with it back. Now the water heater breaker doesn't trip but the ac relay light is still on at the dino board. I even swapped the wire again with another breaker that is exactly the same again to see if the breaker is screwed up. But again didn't pop the breaker and the dinoboard still lit up with ac relay. Where is the ac relay and has anyone else had this light go off on their board?

[Barryfish]

Also the light turns off when I switch it to LP. But my LP has never worked so would like to get it running back on AC. We live in this motorhome

[camper8251]

I believe yellow is normal for AC operation.
Sounds like something is bad in Heater.
Call the company you bought the board from.

[Glennabbott1]

Heck voltage at the heating element. If voltage is correct you can then check the element resistance. You may want to google this to help troubleshoot your problem.

[Barryfish]

The dinosaur board has 3 different lights on it. 1 is green for power, 1 is red for open valve and then the yellow light is for ac relay. It's labeled as diagnostic LEDs. I wonder if the yellow is always supposed to be on. I will check to see if I have hot water In a few hours. Hopefully my tank just needs to get warm again.

[Old-Biscuit]

You didn't state BRAND of water heater....sounds like an Atwood
Also sounds like the Dino is the UIB 64 version



Atwood uses 12VDC to BOTH on/off switches which then send DC to circuit board
On Electric DC is sent to a DC relay that when closed allows 120VAC to go to element
Sometimes the AC wire on that DC Relay is bad/loose/insulation melts and causes AC CB to trip
***DC relay and element are on backside of WH Tank under the protective cover.

Caution: 12VDC AND 120VAC present



Dino Board has 3 diagnostic LEDS
Green......Board has DC Power or is in CHECK (after 3 failed attemts to light flame)
RED.........Comes on when DC is on Gas Valve
Yellow....... comes on when board is applying DC to the AC Circuit (should be on when using AC Element....OFF if using GAS)

[Barryfish]

So that yellow light should always be on then? I never run gas on it. There is no flame when you try to run gas but that's a whole different issue. It's been that way for 2 years and I never worry about it cause we stay plugged into shore power. I never noticed the yellow light on when it was working. Do you have to pull the water heater out to change the relay? Yes it's an Atwood sorry, should have stated that.

[Old-Biscuit]

"Do you have to pull the water heater out to change the relay?"

YES --- Maybe --- NO


Depends on if you have adequate access to backside of water heater tank
Rear removal panel, removable panel in a compartment next to it, removable panel from under neath ????
No access.....then have to PULL whole unit out (disconnect propane line, disconnect wiring remove caulking etc.




WHY doesn't propane work?
No Spark?
No gas flow?
Lites off but doesn't stay lit?


Most propane issues are just dirty orifices, dirty burner tube, dirty/obstructed combustion chamber, grounded spark electrode

[Barryfish]

WHY doesn't propane work?
No Spark?
No gas flow?
Lites off but doesn't stay lit?


Most propane issues are just dirty orifices, dirty burner tube, dirty/obstructed combustion chamber, grounded spark electrode[/QUOTE]

No flame, doesn't make a sound or anything. Never looked into why it doesn't work but if it's cheaper to fix the gas portion of it I'll do that.

[Old-Biscuit]

Here is the wiring schematic for your Atwood WH
New Dino Board so GAS circuit should work........easy to follow GAS DC circuit using a voltmeter


Dirty/loose connectors
Spark Electrode bad....connections dirty/loose
Grounds not clean/tight


*Dirty burner tube....remove and clean using small bottle brush

*Dirty orifice...unscrews from gas valve after removing burner tube----soak it in alcohol then blow thru opening to dry (just blow on it using mouth---air compressor can damage the metered hole and no poking anything thru the metered hole)
*Spark Electrode....remove assembly. Clean up electrode using emery cloth, Electrode wire should not be loose in the ceramic insulator (replace if it is or if ceramic is cracked).
Electrode wire connection to transformer on circuit board needs to be clean/tight
Electrode GAP should be 1/8" - 3/16" and needs to be engulfed in flame
Electrode assembly mounting screw provides ground so screw connection should be clean/tight


With water temp below 110*F (point where T-stat closes for heating cycle) turn GAS switch ON and trace the DC circuit/
DC on orange wire
DC on Brown wire to t-stat and back to circuit board
DC on Red wire to ECO and to gas valve....at which time spark electrode should be firing (CLICK, CLICK, CLICK)
***Both gas solenoids have to work for gas valve to open