Magic Chef Gas - No Light

Magic Chef gas - no light

Chris -- Tuesday, 17 December 2002, at 11:52 a.m.

My Magic Chef propane oven quit igniting after I tried to use with a generator during power outage.

Local repair shop replaced the ignitor bar (which I already new wasn't the problem). Now they want $185 to replace the valve. No one has yet arrived with a volt meter. I don't want to pay for every part until they find the bad one.

Broiler works. I have power out of digital control board when I turn oven ON. No power at ignitor. I don;t understand how the valve works. Do you have any advice on troubleshooting it? I have power to it, when I turn oven ON. What tells it that the ignitor is hot and to turn gas on? Terminals on other side of valve get no power and both seem to be grounded(??).

Does this valve control power to ignitor bar?

I assumed that the control board was the most likely thing to be damaged by a generator but it seems to be ok.

Thanks
Chris

Re: Magic Chef gas - no light

Dan O. -- Tuesday, 17 December 2002, at 2:10 p.m.

: My Magic Chef propane oven quit igniting after
: I tried to use with a generator during power
: outage.

: Local repair shop replaced the ignitor bar
: (which I already new wasn't the problem).
: Now they want $185 to replace the valve. No
: one has yet arrived with a volt meter. I
: don't want to pay for every part until they
: find the bad one.

Were they a Magic Chef authorized service company? If not, that is whom I suggest you have service that product. BTW. Magic Chef is now owned by Maytag so one of their agents would likely be authorized for Magic Chef brands as well.

: Broiler works. I have power out of digital
: control board when I turn oven ON.

There may (very likely in fact) be separate power relays for the bake and broil circuit so just the broil working does not necessarily mean the control is good.

: No power at ignitor. I don;t understand how the
: valve works.

If you have an Adobe Acrobat .PDF file reader, you can read how bake/broil valves on hot surface ignition ovens work at the following link:

LINK > How a gas range's bake/broil oven valve works

: Do you have any advice on troubleshooting it?

You can see a simplified wiring diagram with test procedures at the following link:

LINK > Hot Surface Ignitors Troubleshooting

: I have power to it, when
: I turn oven ON. What tells it that the
: ignitor is hot and to turn gas on?

When the ignitor reaches a specific temperature, its resistance changes to that which will allow the proper current to flow to the oven valve to allow it to open.

: Does this valve control power to ignitor bar?

The ignitor is like a big resister that is in series with the oven valve. The oven valve does not power it.

: I assumed that the control board was the most
: likely thing to be damaged by a generator
: but it seems to be ok.

There is very likely to be separate power relays for the bake and broil circuit so just the broil working does not necessarily mean the control is good.

I guess the oven valve could be susceptible to power functions but I would think the electronic control would be the most likely to be affected.

Dan O.

Maytag Parts, Service, Dealer Locator

Re: Magic Chef gas - no light

Chris -- Wednesday, 18 December 2002, at 7:41 a.m.

Dan,

It does have a Maytag id on it, and yes, there are seperate relays for bake and broil. When I said the controler seemed ok, I meant that I get power at the BAKE terminal of the board when I turn the bake function ON. I also have power to the BAKE side of the valve, so the wires are good, at least.

Thanks very much for the links! Very informative.
Just what I was looking for.

If I end up replacing the valve, I'll dissasemble it, to see what went wrong. (No core charge)

I called the Maytag guys first, but couldn't afford them... also couldn't wait that long for my oven... Christmas baking and all. They have, however agreed to get the part for me.

Thanks again,
Chris

Re: Magic Chef gas - no light *LINK*

Dan O. -- Wednesday, 18 December 2002, at 2:39 p.m.

: It does have a Maytag id on it, and yes, there
: are seperate relays for bake and broil. When
: I said the controler seemed ok, I meant that
: I get power at the BAKE terminal of the
: board when I turn the bake function ON. I
: also have power to the BAKE side of the
: valve, so the wires are good, at least.

Sounds like the control may be Ok too.

: Thanks very much for the links! Very
: informative. Just what I was looking for.

Glad to hear it.

: If I end up replacing the valve, I'll
: dissasemble it, to see what went wrong. (No
: core charge)

You can see an animated illustration of how they're suppose to work below.

: I called the Maytag guys first, but couldn't
: afford them...

That's what a lot of people think until they call the cheapest company they can find and it ends up costing them more (higher parts mark-up, more labour, etc.) or taking longer because of inexperience (how long has it been so far?). I'm not saying all independent servicers are, but...

: also couldn't wait that long for my oven...

Understandable but there are usually several authorized factory service outlets in any town (see the link below). If one is too booked up to come quickly, try another.

: They have, however agreed to get the part
: for me.

That's a deal. Let us know how you make out.

Dan O.

Maytag Parts, Service, Dealer Locator

Re: Magic Chef gas - no light

Chris -- Thursday, 19 December 2002, at 9:23 p.m.

Ok Dan, here's an update.

On further inspection, I notice a sticker on the valve (dual valve, by the way) that says DO NOT HOOK 120VAC TO VALVE. It says it's a 3.3V valve.
This valve has 2 gas outlets, and 4 terminals... 2 on each side. On one side is a white neutral and red going to the BAKE ignitor. On the other side is a white neutral (also jumps from BAKE side) and a yellow going to the BROIL ignitor.

The BAKE side of the valve has 3V on it when OFF & 120 when on?!? The BROIL side (which is the side that works) has 0V when off and 3.3V when on.

Same deal at the BAKE and BROIL terminals of the control board (they are marked).

Am I missing something here, or does it sound like the control board is bad?

Thanks for your patience... I'm trying to learn something here.

Re: Magic Chef gas - no light

Dan O. -- Friday, 20 December 2002, at 2:12 p.m.

: The BAKE side of the valve has 3V on it when
: OFF & 120 when on?!? The BROIL side
: (which is the side that works) has 0V when
: off and 3.3V when on.

: Same deal at the BAKE and BROIL terminals of
: the control board (they are marked).

: Am I missing something here, or does it sound
: like the control board is bad?

I'm not familiar with your exact model or know how you're testing for voltage, but if the ignitor glows when the oven is turned on, it must be getting power from the control which I would think would mean it is good. If it were bad, it wouldn't provide power to the ignitor so the ignitor shouldn't even glow.

Dan O.

Re: Magic Chef gas - no light

Chris -- Friday, 20 December 2002, at 2:15 p.m.

: I'm not familiar with your exact model or know
: how you're testing for voltage, but if the
: ignitor glows when the oven is turned on, it

Broil ignitor does glow (and light)... Bake ignitor doesn't.

: must be getting power from the control which
: I would think would mean it is good. If it
: were bad, it wouldn't provide power to the
: ignitor so the ignitor shouldn't even glow.

: Dan O.

Re: Magic Chef gas - no light

Dan O. -- Friday, 20 December 2002, at 6:27 p.m.

:: does it sound like the control board is bad?

: Broil ignitor does glow (and light)... Bake
: ignitor doesn't.

You said previously,

When I said the controler seemed ok, I meant that I get power at the BAKE terminal of the board when I turn the bake function ON. I also have power to the BAKE side of the valve, so the wires are good, at least.

If power is getting to the bake side of the valve when bake is selected, the board must be providing that power which I would take to be a sign that the board is Ok.

Dan O.

Re: Magic Chef gas - no light

Chris -- Friday, 20 December 2002, at 7:04 p.m.

: If power is getting to the bake side of the
: valve when bake is selected, the board must
: be providing that power which I would take
: to be a sign that the board is Ok.

It is getting power... 120v. I had assumed this was normal until I saw the sticker on the valve about not connecting 120v to it. Now I'm having second thoughts because the broil side gets 3.3V.
See what I'm getting at?

I would hate to install a new valve and have an improper voltage (120 instead of 3.3) fry it.

Re: Magic Chef gas - no light

Dan O. -- Friday, 20 December 2002, at 11:06 p.m.

: It is getting power... 120v. I had assumed this
: was normal until I saw the sticker on the
: valve about not connecting 120v to it. Now
: I'm having second thoughts because the broil
: side gets 3.3V. See what I'm getting at?
: I would hate to install a new valve and have an
: improper voltage (120 instead of 3.3) fry it.

The 3.3 volts is achieved by running the current through the ignitor which is basically just a big resistor. The only way I can see the full 120 volts getting to the bake valve is if the ignitor was totally shorted or there was a short elsewhere in the circuit.

As I stated previously, I don't know how you are testing for voltage. Normally, at least one line of the circuit should be disconnected and voltage tested between it and the rest of the circuit bypassing the component in question. Otherwise, you may be reading a backfeed through the rest of the circuit.

For example, if the voltage at a dryer's element was in question, the wires would be disconnected from the element and the voltage between those 2 wires would be tested.

Dan O.

Success! Magic Chef gas - no light

Chris -- Saturday, 21 December 2002, at 8:57 p.m.

: The 3.3 volts is achieved by running the
: current through the ignitor which is

: basically just a big resistor. The only way
: I can see the full 120 volts getting to the
: bake valve is if the ignitor was totally
: shorted or there was a short elsewhere in
: the circuit.

*Doh! (slapping forhead) NOW I get it!

: As I stated previously, I don't know how you
: are testing for voltage. Normally, at least
: one line of the circuit should be
: disconnected and voltage tested between it
: and the rest of the circuit bypassing the
: component in question. Otherwise, you may be
: reading a backfeed through the rest of the
: circuit.

Yes, and I bypassed the ignitor, not even considering it's effect on the voltage. It all seems so simple now. For some reason it seems alien to me to see an AC circuit in series like that. Your first line above FINALLY clicked the light on for me.

Danno, thanks a million!
Oven works great, saved a buck, and the best thing about it, is that I understand it now!

Your website is an unbelievable resource.
Thank you for being so patient with me.

Chris

Re: Success! Magic Chef gas - no light

Dan O. -- Sunday, 22 December 2002, at 12:39 p.m.

: *Doh! (slapping forhead) NOW I get it!

: Yes, and I bypassed the ignitor, not even
: considering it's effect on the voltage.
: It all seems so simple now. For some reason
: it seems alien to me to see an AC circuit in
: series like that.

One of the fist illustrations I linked to showed exactly that.

: Oven works great, saved a buck, and the best
: thing about it, is that I understand it now!

Glad to hear it. Have a happy holiday.

Dan O.
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