Dometic refrig,curcuit boards

It is likely the voltage selector board, the smaller of the two, that is bad. In the past Jandy has recommended changing the heater over to 115V as a better option if you keep loosing the board(s). I forget their exact logic as to why but the last one of those I had behave like this was a few years ago and once we replaced all the burned up electronics and converted the power and the heater over to 115 it never failed again.

Perhaps Jandy would explain further if you need additional info, try calling:
1-800-822-7933

There are solder in slow burn fuses located on the circuit board that can burn out if the pump gets clogged or broken and some other reasons that you can buy from Mouser electronics using p/n (mouser) 576-37416300410 or Mfg p/n 37416300410. The fuses are reddish, round cylinders about .5 inch high and wide. Anyone who can solder can easily fix this. Be sure to tag any connections that you remove although all you need to do to get the circuit board out to work on it is remove the small rubber hose and 2 electrical plugs connected to the board through the outside cover. There is paperwork inside the head of the machine (and there is the circuit board) with fault codes to help you determine what your specific problem could be but I had a no power problem recently and replacement of these 2 fuses fixed it. Let me know if you need further help!
Good luck!

Have you tried locating the connectors on circuit board for the AC (hydro) element and removing them from circuit board and see what happens when you turn it on hydro then? Follow them back from element if necessary. If fuse doesn't pop, then I'd suspect a shorted element and change the heating element. Double check fuse is correct amperage as well. If it's a 3 way fridge, make sure it's the AC element and not the 12 volt you remove.

Check the 110 volt wire for flaws. Take a volt meter and check the recep that the fridge plugs into for power, should be 110 volts or so. +/- 10%. If you have power at the recep problem is in the fridge chord or circuit board fuse or circuit board. Also check the 110 volt breaker in the coach at the service panel.

Check to see if your boiler tube is hot. If it is , your cooling unit is shot. Do not plug your circuit board into 110 volt power that will destroy it. To test your heating elements you need to do an ohms reading on the elements. But I can tell you from experience if your boiler tube/ this is the 3-4" diameter sheet metal tube going up the back of the refer/ is hot the cooling unit is no good. If you would like to discuss your diagnostics give me a call.
Jerry
[email protected]
734 777 6432
www.coachtech.info

Most likely your heating element burned out or else the circuit board is bad. To test the heating element unplug it from the circuit board (j6 and j7 usually gold colored) take the two heating element wires and using an ohm meter make sure there is no resistance between them, if there is resistance the heating element is bad, Or can just put a plug onto the heating element and plug it into a 110 wall outlet and see if it gets hot. If it is not the heating element it is most likely the main circuit board. (between 1993-1996 dometic used a yellow epoxy filled circuit board that went out pretty quickly) if you have the yellow filled circuit board rather than the green one it is most likly the circuit board

This sounds like the curcuit board has failed. No repair is able to be made to the board. Just replace the board and all should be fine..

Okay. now what you have to do is plug one crt back in and try it if the fuse doesnt blow then plug in the second CRT and try it again. then if it still doesnt blow with the two CRts plugged in then plug in the last crt if it blows thats the bad crt, and it will need to be replaced. But when you plug in the bad CRT the fuse will blow. Then let me know which tube as I have a good source for mitsubishi CRTs at real cheap prices.

Have him check power suply link, from fuse to wall plug, theres a short some where between the plug and the fuse.