Whirlpool gas oven ps/control board burnt resistor

[CapLeaker]

Re: Whirlpool gas oven ps/control board burnt resistor

its a viper12a, post #14

[R_J]

Re: Whirlpool gas oven ps/control board burnt resistor

I must have missed that, so the board could be a universal input, if that's the case the main filter should be rated at 450v. but it is only connected across L1 and neutral, according to the diagram so that would be 120vac. A simple check of the ac input to the board could confirm it.

[CapLeaker]

Re: Whirlpool gas oven ps/control board burnt resistor

I actually think there is nothing much wrong with that little supply. Maybe that L3 that has a crack and needs to be replaced. I believe that something draws too much from that supply causing r71 to open. Instead of looking at the PSU, we should be looking at whatever uses this supply.

[R_J]

Re: Whirlpool gas oven ps/control board burnt resistor

There is nothing else that uses the supply other than the controller itself, the oven temp sensor would be minimal, the door position switch would be nothing, the only extra current draw would be when a relay coil is energized and that would only be a few milliamps extra. The fan motor, oven elements etc. are only "switched" by the relay contacts, and don't draw current from the controller. If it works on the bench it should work in the stove.

Maybe it was being installed with the stove live? and something touched ground during the install?

[redwire]

Re: Whirlpool gas oven ps/control board burnt resistor

All outputs from the board are done with mains relays. Bake, Broil, Convection fan, Oven Light.
Only the board's inputs- door lock switch and temperature probe input are the other connections that could cause trouble.

If the board does power up OK on the bench, then I say there is a ground fault in the inputs, or a wiring mistake when installing the board.

I'm not sure what Q14 (TO-220) is doing. It's the only other power component. Must be a 7805.

Whirlpool W10349742 Rev. FV3.12, SF5113
Robertshaw LCC190 Electronic Range control

[CapLeaker]

Re: Whirlpool gas oven ps/control board burnt resistor

I dunno... maybe there is a wire somewhere pinched to the metal grounding it out and it has to be an input, not anything that is hooked to the relays. Only thing one can do is to just put the board in by itself and nothing connected, then plug in one thing after the other, until r71 blows again. I am not sure what Q14 is doing either.

[sam_sam_sam]

Re: Whirlpool gas oven ps/control board burnt resistor

If the controller board runs off of 120 volts and works fine on the bench

I would strongly recommend that you check and make sure that you have a good neutral because most controller boards are 110 volts I have only seen a few of them that were 220 volts

Most of the time the board will tell you what voltage they are if this one does not then check the two wires that power the controller ( on the oven or range ) and see what voltage you are getting

I would check the neutral wire with a 100 watt incandescent bulb not a meter because you might get fandom voltage feedback you want to test this way ( L1 to neutral ) and L2 to neutral ) to know for sure that you have a good neutral on the outlet

Next ( the power cord going to the range or oven ) ———>

Use Caution doing this part———>

on the back of the unit be careful doing this one because the power cord ( lugs ) most power cord are very short most of time and may not give very much room to test it this way with out using a lamp cord hook on the power cord lugs

If it test good then you need make sure that you do not have a short to ground on the range or oven that is hook to the controller board

Or you could do this that was suggested earlier but I would use a bulb that is used in small night light old school ( incandescent ) in place of the resistor that keeps burning out because this resistor in this circuit the way you show it in your diagram is no more than a fuse

One note if this light bulb is very bright then you have a big problem you need find out why you are pulling this much current

Only thing one can do is to just put the board in by itself and nothing connected, then plug in one thing after the other, until r71 blows again. I am not sure what Q14 is doing either.

I hope this helps you

[greezmky]

Re: Whirlpool gas oven ps/control board burnt resistor

We need not speculate any further and I APPRECIATE everyones contributions!!!!

Ultimately the procedure was similar to what we all have discussed in the last few posts. I plugged in the board with a hot and neutral in the stove. All the connectors are spades in molded plastic so I hooked up the dc side plug only and began testing voltages out as my brother picked bake, broil, etc. The light showed hot no matter what but only like 70vac, so I proceeded to desolder the K1 relay. We tested it with a 9v battery and it was good, that left us scorching our heads, soldered it back in and it had 110vac out?

At this point we decided it was time to sacrifice another R71 but I got to watch as my brother used a power strip (so that we had a switch). Upon turning on the switch there were sparks and a burnt resistor but the sparks were from the door light switch ??????. I had tested that all and even had that connector plugged in so all the dc stuff was powered with not ac stuff powered. I replace R71 and unplugged the switch for the door light and tested, now it is working!!!!

We decided for now it was best to jump out the switch and tape it up so that my mom still has a switched light just no automatic on light when the door opens.

Why this caused too much draw on the ac side I do not know as it is controlled by dc seems as if it would have killed something on that side?



The Issue:


Exploded:


Normally I would take it all apart and clean/fix but not taking the chance here.

Thank you ALL VERY MUCH!!!!!!

[sam_sam_sam]

Re: Whirlpool gas oven ps/control board burnt resistor

Well I am glad that you figured out what was causing your problem

What happens when you hook the two wires together with out the switch does it still burn out the resistor

If the inside the switch has a crack and has a carbon track to ground that would explain why you were having this problem

[greezmky]

Re: Whirlpool gas oven ps/control board burnt resistor

Well I am glad that you figured out what was causing your problem

If the inside the switch has a crack and has a carbon track to ground that would explain why you were having this problem

Thank you

I see no crack but the carbon track could be it, who knows it is the most actuated switch in the system. My dad was never behind the stove when trying it so he could not see it but it lit up pretty good.

I'm just glad I got it fixed and saved them $250, the switch is an expensive little bugger at $50-$70. I may try to find some other switch though. This one takes a rod from the front to the switch, kind of dumb if you ask me but maybe it gets to hot right under where you would expect the door switch to be.

[R_J]

Re: Whirlpool gas oven ps/control board burnt resistor

I can't see the switch itself causing a problem unless it was shorting to the stove metal chassis. I would check the two wires between the switch and controller, one might be shorted to ground. That could blow the resistor because the power supply is not isolated.
You could check the resistance between each switch wire to metal ground, it should be almost infinite. Check with a used appliance shop, they might have a good used part.

Just a note regarding the switch, the oven self clean feature may not function without the switch.
It looks like there may have been some arcing between the conection and the ground clip, if you choose to reassemble it use the other two holes.

[sam_sam_sam]

Re: Whirlpool gas oven ps/control board burnt resistor

I would not recommend using just any kind of switch for this application because that switch is an input for the controller board if you can use it with out the switch it might be better if you do not want to spend the money on it

The switch case might be made out of Bakelite if this is the case then that would explain why it is exspenive and it is used because of the heat so do not use just any kind of switch for this use a switch that is rated for heat

[redwire]

Re: Whirlpool gas oven ps/control board burnt resistor

Wow, I see where the door switch back-plate carbon-tracked. I would say the lightning arc'd across the bakelite insulation, but not sure what grounded metal is nearby? The mounting clip it did not arc to, it was something outside.

Gotta admit it's a weird problem, door switch shorts and takes out control board.
Parts for this oven are silly expensive. $52 for a door switch and I'm seeing the control board sell for $380! OUCH! You saved the oven from needing to be replaced just due to ripoff repair costs.

W10627802 Range Oven Door Switch is replaced by WP9757262, a newer part.

OP, if you still have electrical problems in the house, it might be getting big overvoltage transients. This failure I would say is due to lightning or repeated spikes on mains and other items in the house might get damaged. A bad neutral can also do it, or bad earth ground in the service. Something to keep an eye out for.

[stj]

Re: Whirlpool gas oven ps/control board burnt resistor

that shit switch would be illegal in europe, the clearance between the contacts and the clip is too small.

[CapLeaker]

Re: Whirlpool gas oven ps/control board burnt resistor

finally! Congrats fixing the range! I never seen a bad door light switch going bad like that. Weird.

[sam_sam_sam]

Re: Whirlpool gas oven ps/control board burnt resistor

I have seen carbon tracking to ground before but it not a common problem but most of the time it happens at higher voltages but if lightning hit near the house that would explain how this could happen

Carbon tracking is something to keep in mind it does happen

It has taken out my garage door opener two different times by lighting hitting near the house and both times it fried the photo electric eyes to the controller board and I ended up having to buy another garage door opener both times because it also fried the controller board as well

It also had carbon tracking in parts of the controller board

[R_J]

Re: Whirlpool gas oven ps/control board burnt resistor

Just a note in post #31 I mentioned the self clean may not work, I was wrong about that, this switch is only for the oven lamp, and not the door lock.

[redwire]

Re: Whirlpool gas oven ps/control board burnt resistor

that shit switch would be illegal in europe, the clearance between the contacts and the clip is too small.

In North America there is one multinational mega-corporation making appliances under a ton of brand names.
Whirlpool Corp. makes Whirlpool, Maytag, KitchenAid, Jenn-Air, Amana, Hotpoint, Sears Kenmore, Inglis, Acros, Diqua, Estate, Brastemp, Bauknecht, Indesit, and Consul etc.

So this oven switch (with a bad design) ends up in a zillion appliances, world wide. I would not be surprised to see it in European appliances.

[greezmky]

Re: Whirlpool gas oven ps/control board burnt resistor

I will not be using the old switch, just not worth the chance of actually killing the board. I have checked all the wiring. I feel like the carbon track is the most viable explanation and that it was arcing on the metal clip which is chassis ground. I guess, sort of tracing the whole board out that the increased load drew too much for the resistor on the ac side.