Just bought a home with the electric range. Oven temp is way too hot,
50-75 degrees. Turned it on about an hour ago to 300, and oven
thermometer is consistently reading 350. Seemed on T'giving it varied
more, but there was a huge turkey in the oven and the door opened
regularly. I'm wondering if anyone has a manual that gives the codes
for calibrating the oven temp setting? I've not used the oven a lot,
but have burned a pie and muffins ) Another issue with this range is
that when I opened the oven door to ck the turkey, I got hit in the face
with a blast of steam...never had that happen, gas or electric. I'm all
for getting gas range ASAP, as there is no longer parts avail. for this one.

On 11/26/2012 11:50 AM, Norminn wrote:
....

... I'm wondering if anyone has a manual that gives the codes for
calibrating the oven temp setting?...


http://www.appliance411.com/faq/temp...ibration.shtml

--

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

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.

On Nov 26, 11:50*am, Norminn wrote:
Just bought a home with the electric range. *Oven temp is way too hot,
50-75 degrees. *Turned it on about an hour ago to 300, and oven
thermometer is consistently reading 350. *Seemed on T'giving it varied
more, but there was a huge turkey in the oven and the door opened
regularly. *I'm wondering if anyone has a manual that gives the codes
for calibrating the oven temp setting? *I've not used the oven a lot,
but have burned a pie and muffins ) *Another issue with this range is
that when I opened the oven door to ck the turkey, I got hit in the face
with a blast of steam...never had that happen, gas or electric. *I'm all
for getting gas range ASAP, as there is no longer parts avail. for this one.

Have you pulled the oven knob off the range to see if there is an
adjusting screw opening behind the knob? If there is, give the screw
a 1/2 turn and see if the oven temp is closer or farther away from the
knob indication. Then keep turning the screw in the appropriate
direction until the knob and the temp agree +/- 10 - 15 degrees.

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.

On 11/26/2012 2:56 PM, dpb wrote:
On 11/26/2012 11:50 AM, Norminn wrote:
...

... I'm wondering if anyone has a manual that gives the codes for
calibrating the oven temp setting?...


http://www.appliance411.com/faq/temp...ibration.shtml

--

This link was helpful....I pulled off the knob for oven temp (there is
another, separate knob, for bake or broil or clean). What a rinky-dink
piece of equipment. The knob has two screws on the back which loosen a
little plastic toothy thing to turn to lower or raise the temp. I
slipped it two notches (10 degrees each notch) to lower the temp. Tried
it out....60 degrees too high with oven on for 20 min; forgot about it
for a while, and after about 90 min the oven was 100 degrees too hot!
So much for that....I want a gas range, so just need to convince HWMBO
) Found a source for a whole new regulator...the "sensor", lead and
regulator....close to $300!! Not surprising, but dang irritating...got
lots of baking to do, and then help grandson with stuff he like to bake.
I had my heart set on a five-burner, but would be happy to get a four
burner, basic 60's style range with no
electronic/automatic/mind-reading/internet communicating crap! Thanks
for help!

I'm going to write my congressperson about appliance companies...pass a
law that requires engineers to USE appliances they design for 1 year
before marketing...my new washer is like watching natives beat their
laundry on rocks in the river )

On 11/27/2012 11:14 AM, Norminn wrote:
....

... The knob has two screws on the back which loosen a
little plastic toothy thing to turn to lower or raise the temp. I
slipped it two notches (10 degrees each notch) to lower the temp. Tried
it out....60 degrees too high with oven on for 20 min; forgot about it
for a while, and after about 90 min the oven was 100 degrees too hot! So
much for that...

So, you went the wrong way, apparently. Do the same thing except the
other direction. I'd recommend a single step at a time.

I've never had any trouble getting an electric oven to hold temperature
well near enough to setpoint...

--

On 11/27/2012 12:28 PM, dpb wrote:
On 11/27/2012 11:14 AM, Norminn wrote:
...

... The knob has two screws on the back which loosen a
little plastic toothy thing to turn to lower or raise the temp. I
slipped it two notches (10 degrees each notch) to lower the temp. Tried
it out....60 degrees too high with oven on for 20 min; forgot about it
for a while, and after about 90 min the oven was 100 degrees too hot! So
much for that...

So, you went the wrong way, apparently. Do the same thing except the
other direction. I'd recommend a single step at a time.

I've never had any trouble getting an electric oven to hold temperature
well near enough to setpoint...

--

It had that much variation when I baked pies for T'giving...I'm done )

On Nov 27, 12:28*pm, dpb wrote:
On 11/27/2012 11:14 AM, Norminn wrote:
...

... The knob has two screws on the back which loosen a
little plastic toothy thing to turn to lower or raise the temp. I
slipped it two notches (10 degrees each notch) to lower the temp. Tried
it out....60 degrees too high with oven on for 20 min; forgot about it
for a while, and after about 90 min the oven was 100 degrees too hot! So
much for that...

So, you went the wrong way, apparently. *Do the same thing except the
other direction. *I'd recommend a single step at a time.

I've never had any trouble getting an electric oven to hold temperature
well near enough to setpoint...

--

It sounds lie all the adjustment procedure does is
move the relative position of the know to the shaft.
In which case, it would have to work. Unless something
is screwed up in the thermostat so that it's intermittent,
not consistent, etc.

On 11/27/2012 12:05 PM, wrote:
....

It sounds lie all the adjustment procedure does is
move the relative position of the know to the shaft.
In which case, it would have to work. Unless something
is screwed up in the thermostat so that it's intermittent,
not consistent, etc.

Correct...

The setpoint adjustment will bring the steady-state temp to near the
indicated.

If there is an excessive variation in temperature at what should be
steady-state, that's not a calibration issue.

--

In article ,
Norminn wrote:

On 11/27/2012 12:28 PM, dpb wrote:
On 11/27/2012 11:14 AM, Norminn wrote:
...

... The knob has two screws on the back which loosen a
little plastic toothy thing to turn to lower or raise the temp. I
slipped it two notches (10 degrees each notch) to lower the temp. Tried
it out....60 degrees too high with oven on for 20 min; forgot about it
for a while, and after about 90 min the oven was 100 degrees too hot! So
much for that...

So, you went the wrong way, apparently. Do the same thing except the
other direction. I'd recommend a single step at a time.

I've never had any trouble getting an electric oven to hold temperature
well near enough to setpoint...

--

It had that much variation when I baked pies for T'giving...I'm done )

Go ahead and get the gas range, but don't blame the technology for your
choice. And yes, you did, obviously, turn the adjustment the wrong way.

I actually know something about temperature control, having designed a
few pieces of industrial equipment that use temperature controllers.
Inherent in any control system is some fluctuation above and below the
set point. Fancy word for that is hysteresis.

The thing about gas vs. electric with an oven is that the hysteresis
band can be much smaller with electric, because it's easier to
proportion the heater power. You'd be shocked at the width of the
temperature swings inside that gas oven of your dreams.

The thing about gas vs. electric with a cooktop is that although it's
much easier to precisely set a desired temp with electric, there is a
huge delay in response when you want to change that temperature. With
gas it's instantaneous, (not counting the thermal mass of whatever
you're cooking.)

Many people who love to cook choose the best of both by buying a dual
fuel range: gas cooktop and an electric oven. You might consider it.

On 11/27/2012 1:26 PM, Smitty Two wrote:
In article ,
Norminn wrote:

On 11/27/2012 12:28 PM, dpb wrote:
On 11/27/2012 11:14 AM, Norminn wrote:
...

... The knob has two screws on the back which loosen a
little plastic toothy thing to turn to lower or raise the temp. I
slipped it two notches (10 degrees each notch) to lower the temp. Tried
it out....60 degrees too high with oven on for 20 min; forgot about it
for a while, and after about 90 min the oven was 100 degrees too hot! So
much for that...

So, you went the wrong way, apparently. Do the same thing except the
other direction. I'd recommend a single step at a time.

I've never had any trouble getting an electric oven to hold temperature
well near enough to setpoint...

--

It had that much variation when I baked pies for T'giving...I'm done )

Go ahead and get the gas range, but don't blame the technology for your
choice. And yes, you did, obviously, turn the adjustment the wrong way.

Obviously? You are dreadfully wrong....turned to lower the temp, per
the little arrow markings. This range seems to have very small vent,
below the panel on top of stove....even after reaching high heat,
holding my hand at the vent I can barely feel a difference in temp from
room temp. When I was roasting turkey on T'giving, opening the oven
door to baste the turkey gave me a blast of steam in the face...never
experienced that with any other oven (I've roasted turkeys for many years).

I actually know something about temperature control, having designed a
few pieces of industrial equipment that use temperature controllers.
Inherent in any control system is some fluctuation above and below the
set point. Fancy word for that is hysteresis.

The thing about gas vs. electric with an oven is that the hysteresis
band can be much smaller with electric, because it's easier to
proportion the heater power. You'd be shocked at the width of the
temperature swings inside that gas oven of your dreams.

Well, shucks, I have cooked with gas ranges for.....hmmm....a total of
about 45 years, beginning rather young. No problems. Cooked with three
other electrics, few years, no problems. One gas range I used for a
couple of years was way off temp setting (too hot), but the temp was
consistent so it was easy to simply set oven temp to lower temp.

The thing about gas vs. electric with a cooktop is that although it's
much easier to precisely set a desired temp with electric, there is a
huge delay in response when you want to change that temperature. With
gas it's instantaneous, (not counting the thermal mass of whatever
you're cooking.)

Many people who love to cook choose the best of both by buying a dual
fuel range: gas cooktop and an electric oven. You might consider it.

Thanks, but I much prefer gas.

On Tuesday, November 27, 2012 2:18:43 PM UTC-5, NorMinn wrote:
Obviously? You are dreadfully wrong....turned to lower the temp, per
the little arrow markings.

Yes, obviously. You turned it the wrong way.

The direction you turned it causes the dial to INDICATE a lower temperature for the position of the control. Turn it the other way to cause the dial to indicate a *higher* temperature.

Also, your vent is plugged, which is why you're getting this "blast of steam" you're hell-bent on obsessing about.

But you're gonna chuck the oven anyway, so why cop an attitude over it? You asked the question. Don't act like a petulant know-it-all when someone gives you the answer.

On 11/27/2012 3:00 PM, wrote:
On Tuesday, November 27, 2012 2:18:43 PM UTC-5, NorMinn wrote:
Obviously? You are dreadfully wrong....turned to lower the temp, per
the little arrow markings.

Yes, obviously. You turned it the wrong way.

The direction you turned it causes the dial to INDICATE a lower temperature for the position of the control. Turn it the other way to cause the dial to indicate a *higher* temperature.

Guess I missed you lookin' over my shoulder whilst I did the adjusting.
It APPEARS that the dial setting is not proportional to the excess
temperature and the temp varies a great deal.....a sign the sensor
thingy is shot?

Also, your vent is plugged, which is why you're getting this "blast of steam" you're hell-bent on obsessing about.

Steam burns aren't fun, and opening the oven is like taking the lid off
a boiling pot while facing right into it. I'm not obsessing about it,
just feel it is unusual. Per my uneducated glance at schematic for the
range, there is only a small (1"?) tube venting the oven....can't see
the opening of the vent atop the range, as there is a steel flange
sticking out of the opening.



But you're gonna chuck the oven anyway, so why cop an attitude over it? You asked the question. Don't act like a petulant know-it-all when someone gives you the answer.

Ditto.

most older thermostat controls..........

pull knob, see hole in middle of shaft use small jewlers type
screwdriver to turn that screw buried in hole.....

over the years of my job i have made thousands of adjustments to thse
type thermostats on dry mount presses and t shirt presses

Norminn wrote:
On 11/27/2012 1:26 PM, Smitty Two wrote:
In article ,
Norminn wrote:

On 11/27/2012 12:28 PM, dpb wrote:
On 11/27/2012 11:14 AM, Norminn wrote:
...

... The knob has two screws on the back which loosen a
little plastic toothy thing to turn to lower or raise the temp. I
slipped it two notches (10 degrees each notch) to lower the temp. Tried
it out....60 degrees too high with oven on for 20 min; forgot about it
for a while, and after about 90 min the oven was 100 degrees too hot! So
much for that...

So, you went the wrong way, apparently. Do the same thing except the
other direction. I'd recommend a single step at a time.

I've never had any trouble getting an electric oven to hold temperature
well near enough to setpoint...

--

It had that much variation when I baked pies for T'giving...I'm done )

Go ahead and get the gas range, but don't blame the technology for your
choice. And yes, you did, obviously, turn the adjustment the wrong way.

Obviously? You are dreadfully wrong....turned to lower the temp, per the
little arrow markings. This range seems to have very small vent, below
the panel on top of stove....even after reaching high heat, holding my
hand at the vent I can barely feel a difference in temp from room temp.
When I was roasting turkey on T'giving, opening the oven door to baste
the turkey gave me a blast of steam in the face...never experienced that
with any other oven (I've roasted turkeys for many years).

I actually know something about temperature control, having designed a
few pieces of industrial equipment that use temperature controllers.
Inherent in any control system is some fluctuation above and below the
set point. Fancy word for that is hysteresis.

The thing about gas vs. electric with an oven is that the hysteresis
band can be much smaller with electric, because it's easier to
proportion the heater power. You'd be shocked at the width of the
temperature swings inside that gas oven of your dreams.

Well, shucks, I have cooked with gas ranges for.....hmmm....a total of
about 45 years, beginning rather young. No problems. Cooked with three
other electrics, few years, no problems. One gas range I used for a
couple of years was way off temp setting (too hot), but the temp was
consistent so it was easy to simply set oven temp to lower temp.

The thing about gas vs. electric with a cooktop is that although it's
much easier to precisely set a desired temp with electric, there is a
huge delay in response when you want to change that temperature. With
gas it's instantaneous, (not counting the thermal mass of whatever
you're cooking.)

Many people who love to cook choose the best of both by buying a dual
fuel range: gas cooktop and an electric oven. You might consider it.

Thanks, but I much prefer gas.

Gas ovens produce more kitchen heat, because it's vented into the room.
Electrics have minimal venting.

Greg

On 26/11/2012 4:30 PM, nestork wrote:
You should be aware that ovens purchased within the last 20 years no
longer use thermostats to control their temperature.

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 i
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.
emperature



I checked the accuracy of the oven temperature of a new stove when I
purchased it a few years ago, using a calibrated thermocouple readout
with an accuracy of +/- 2°F. I placed the probe in the centre of the
oven and monitored the temperature to see the variability at set points
of between 250 and 450°F. I was quite surprised at the huge cycle swings
in the oven's temperature.

I found the controller cycled on and off within +/- 25°F of the set
point, with an additional lag of 25°F in the response of the elements,
for at total cycle range of +/- 50°F, over a total cycle time of
something like 20 or 25 minutes. Although it was difficult to measure
with the big cycles, I estimated the average temperature would have been
close to the set point. I wish I would have checked the oven in
convection mode to see how much it affected the cycle profile. If I do
this test again, I'll use a less responsive oven thermometer, as long as
I check its accuracy first. Ovens have their control sensors immersed in
an oil bulb to temper these swings and somewhat mimic the response of
food cooking.

I suspect this is typical performance for an electric range and it works
well for me as my food typically cooks in the expected time.

WRP wrote:
On 26/11/2012 4:30 PM, nestork wrote:
You should be aware that ovens purchased within the last 20 years no
longer use thermostats to control their temperature.

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 i
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.
emperature



I checked the accuracy of the oven temperature of a new stove when I
purchased it a few years ago, using a calibrated thermocouple readout
with an accuracy of +/- 2°F. I placed the probe in the centre of the oven
and monitored the temperature to see the variability at set points of
between 250 and 450°F. I was quite surprised at the huge cycle swings in
the oven's temperature.

I found the controller cycled on and off within +/- 25°F of the set
point, with an additional lag of 25°F in the response of the elements,
for at total cycle range of +/- 50°F, over a total cycle time of
something like 20 or 25 minutes. Although it was difficult to measure
with the big cycles, I estimated the average temperature would have been
close to the set point. I wish I would have checked the oven in
convection mode to see how much it affected the cycle profile. If I do
this test again, I'll use a less responsive oven thermometer, as long as
I check its accuracy first. Ovens have their control sensors immersed in
an oil bulb to temper these swings and somewhat mimic the response of food cooking.

I suspect this is typical performance for an electric range and it works
well for me as my food typically cooks in the expected time.

I don't know how long you waited for the thing to stabilize. You would
normal put the test sensor where the other sensor is. Sensor response
should be fast. Makes no sense to be slow. A good controller will determine
the on/off points, not the sensor. It can also use PID which acts to
control overshoot and would know the response of the heater elements.
Question is, do any models have good controllers.

I don't understand why you didn't test turbo oven mode. I can't even get
even temperature in a beaker of water unless it's being rapidly stirred.

Greg

gregz wrote:
WRP wrote:
On 26/11/2012 4:30 PM, nestork wrote:
You should be aware that ovens purchased within the last 20 years no
longer use thermostats to control their temperature.

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 i
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.
emperature



I checked the accuracy of the oven temperature of a new stove when I
purchased it a few years ago, using a calibrated thermocouple readout
with an accuracy of +/- 2°F. I placed the probe in the centre of the oven
and monitored the temperature to see the variability at set points of
between 250 and 450°F. I was quite surprised at the huge cycle swings in
the oven's temperature.

I found the controller cycled on and off within +/- 25°F of the set
point, with an additional lag of 25°F in the response of the elements,
for at total cycle range of +/- 50°F, over a total cycle time of
something like 20 or 25 minutes. Although it was difficult to measure
with the big cycles, I estimated the average temperature would have been
close to the set point. I wish I would have checked the oven in
convection mode to see how much it affected the cycle profile. If I do
this test again, I'll use a less responsive oven thermometer, as long as
I check its accuracy first. Ovens have their control sensors immersed in
an oil bulb to temper these swings and somewhat mimic the response of food cooking.

I suspect this is typical performance for an electric range and it works
well for me as my food typically cooks in the expected time.

I don't know how long you waited for the thing to stabilize. You would
normal put the test sensor where the other sensor is. Sensor response
should be fast. Makes no sense to be slow. A good controller will determine
the on/off points, not the sensor. It can also use PID which acts to
control overshoot and would know the response of the heater elements.
Question is, do any models have good controllers.

I don't understand why you didn't test turbo oven mode. I can't even get
even temperature in a beaker of water unless it's being rapidly stirred.

Greg

I would not doubt large swings. I never measured a home oven, although I
have done a lot of measurements with lab equipment. A gas oven is most
always on/off, but an electric oven could use pulsed currents to vary the
heating element average wattage. I guess most people are used to averages
in oven timing.

Greg

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.

In article ,
nestork wrote:

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.

Cite? We aren't talking about blast furnaces, here. A type J
thermocouple will hold up just fine for the duty cycle and temperature
range of a home baking oven. I don't actually know or care what's
typically used, but the theoretical aging drift of a thermocouple is a
moot point here.

On 11/27/2012 10:26, Smitty Two wrote:

The thing about gas vs. electric with an oven is that the hysteresis
band can be much smaller with electric, because it's easier to
proportion the heater power. You'd be shocked at the width of the
temperature swings inside that gas oven of your dreams.

This is a case where an older gas oven with non-electronic controls can
be advantageous. As the oven nears its set temperature the gas flow is
reduced but not completely cut off. Contrast that with newer models
where the flame cuts off completely when the set point is reached, then
comes back on at full force when the thermostat calls for heat again.
The same phenomenon occurs with electric, but the temperature swing is
not so abrupt due to the slow reaction of the heating coil.