- Model Number
- 721.61289100
Title should have been "Kenmore Microwave with no heat"... sorry.
I've been a tech for years so I'm aware of precautions around HV items. I'm not, however, a microwave oven tech, more just general electronics.
This microwave died about 5 years ago and I found a "donor" almost exact model so I swapped in the donor's magnetron, diode, cap, and transformer, and it has worked just fine since then.
The other day my wife heated some water and it worked fine. A few hours later I went to heat a lunch and got zero heat.
With a digital meter, I see the cap slowly charging as you'd expect, I ran current through the diode from a 9v battery and read battery voltage one way, and about 7.4v the other way so I think it sort of "looks like" a diode. The bimetal fuse reads 0 ohms.
I have read that the magnetron filament should read some fractional part of an ohm, say between .1 and .4 - This one reads 1.6 ohms. This is a Toshiba 2M248J but I can't find what the "correct" filament resistance should be.
On power up, I read total wallplug current at just over 8 amps which says the problem is clearly in HV. So I'm looking for a confirmation that my filament reading is definitely proof the magnetron is gone before buying another one.
I've been a tech for years so I'm aware of precautions around HV items. I'm not, however, a microwave oven tech, more just general electronics.
This microwave died about 5 years ago and I found a "donor" almost exact model so I swapped in the donor's magnetron, diode, cap, and transformer, and it has worked just fine since then.
The other day my wife heated some water and it worked fine. A few hours later I went to heat a lunch and got zero heat.
With a digital meter, I see the cap slowly charging as you'd expect, I ran current through the diode from a 9v battery and read battery voltage one way, and about 7.4v the other way so I think it sort of "looks like" a diode. The bimetal fuse reads 0 ohms.
I have read that the magnetron filament should read some fractional part of an ohm, say between .1 and .4 - This one reads 1.6 ohms. This is a Toshiba 2M248J but I can't find what the "correct" filament resistance should be.
On power up, I read total wallplug current at just over 8 amps which says the problem is clearly in HV. So I'm looking for a confirmation that my filament reading is definitely proof the magnetron is gone before buying another one.
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