nestork wrote:
You should be aware that ovens purchased within the last 20 years no
longer use thermostats to control their temperature.


My furnace thermostat works just fine.

OK, temperature controller.

Thermistors come in various ohm's, but generally not used for high temps,
but i guess there might be some. Platinum wires or thermocouples are
usually used in high temps, but I don't know what the oven makers use.

Greg

Nowadays, they use a thermistor in the oven. The resistance of the
thermistor varies very precisely with temperature, and the circuit board
in the oven console measures that resistance and determines the
corresponding temperature in the oven.

It's possible that the thermistor is gone and you need a new one. If I
recall correctly, at room temperature, the thermistor should have a
resistance of 1000 ohms. Maybe take the thermistor out of your stove
(it looks kinda like an oil filled capillary bulb, but shorter) and take
it down to your local Frigidaire factory authorized service depot and
have them check it for you. There won't be any charge for that.

While it's possible the thermistor is shot, it's probably more likely
that the someone has programmed the oven to operate at a higher
temperature. You see, one of the most common complaints customers have
is that their new stove "just doesn't bake (or broil) like the old one
did", and the usual cause of that is that the old stove had an oil
filled thermostat bulb, and that thermostat was out of whack by 50 or 60
degrees.

So, to address those complaints, programmable ovens can be set so that
they will automatically add or subtract a certain number of degrees to
the temperature you set the stove at so that it will mimic the behaviour
of the customer's old stove. So, if you're used to baking cookies at
350 degrees on an old stove whose thermostat was so far out of whack
that when you set it at 350, the actual oven temperature would only be
300, then you can program your new stove to subtract 50 degrees from
whatever temperature you set. So, when you set the stove to 350, it'll
actually bake the cookies at 300, just like the old stove did.

I suspect that either the previous home owner or someone just mucking
about with the stove got into the programming menu and changed the oven
offset temperature.

I agree with the previous post to go to Jeff's website at
ApplianceAid.com and get his input on it. Jeff's an appliance repair
technician, so he's probably be very familiar with Frigidaire stoves.

Also, you should know that the temperature within the oven will vary by
a good 25 degrees from the front to the back and from the bottom to the
top. You're always going to get some variation between the temperature
reading of an oven thermometer that stays inside the oven during baking
if for no other reason than the thermometer is located at a different
location than the thermistor. However, if you're using an oven
thermometer that uses a clip that you clip to the oven rack, clip it to
the thermistor instead. That way your oven thermometer will be at the
same location as the thermistor, and both your thermometer and the oven
digital read out should be within a degree or two of each other.

Gregz:
I'm quite sure the temperature sensors in my ovens are thermistors. I don't think they'd use thermocouples because thermocouple voltages gradually diminish with use. This is why the thermocouple is the prime suspect if your water heater or furnace pilot light keeps going out. Thermistor resistance doesn't change that way, and so that predictability would make a thermistor better suited for use as a temperature sensor than a thermocouple.

WRP:
My sister was upset when she used an inexpensive supermarket oven thermometer to check the accuracy of the temperature in a brand new stove she had purchased just about two years ago now. It was off by at least 20 degrees; probably more. I borrowed her my digital oven thermometer, and she clipped the probe to the middle of the oven rack as the users manual for the digital thermometer recommended, but she was still getting readings that were considerably different than those displayed on the stove's console. It wasn't until she clipped the probe to the thermistor inside the oven that she got agreement between the two digital displays as to what the oven temperature was at any given time. But, in that case, she was really using my oven thermometer to measure the temperature of the oven's thermistor. But, that shows that the oven's thermistor isn't reading the temperature in the middle of the oven (where the food generally is), but in the top left rear corner of the oven, where the thermistor is, and she found a lot of difference in temperature between those locations.