Oven tempature is 35 degrees celcius less than set tempature even after adjusting oven tempature control

You may find that your new oven cooks differently than the one it replaced. Use your new oven for a few weeks to
become more familiar with it. If you still think your new oven is too hot or too cold, you can adjust the thermostat yourself.
Do not use thermometers, such as those found in grocery stores, to check the temperature setting of your oven.
These thermometers may vary 20-40 degrees.
NOTE: This adjustment will not affect the broiling or the self-cleaning temperatures. The adjustment will be retained
in memory after a power failure.
Adjust the oven thermostat-Do it yourself!
To Adjust the Thermostat
Touch the BAKEand BROIL HI/LOpads
at the same time for 2 seconds until
the display shows SF.
Touch the BAKEpad. A two digit
number shows in the display.
The oven temperature can be adjusted
up to (+) 35°F hotter or (-) 35°F
cooler. Touch the + pad to increase the
temperature in 1 degree increments.
Touch the - pad to decrease the
temperature in 1 degree increments.
When you have made the adjustment,
touch the START/ON pad to go back to
the time of day display. Use your oven
as you would normally.
NOTE: This adjustment will not affect the broiling
or self-cleaning temperatures. It will be retained
in memory after a power failure

First of all, most oven thermometers move very slowly compared to the electronic sensors and controls on the oven. To make sure you are getting an accurate reading, the thermometer should be in the center of the oven, the oven should be preheated, then wait another 20 minutes after the preheat beep. If the temperature is less than 35 degrees higher or lower at this point, it can be adjusted via the controls. Usually on GE ovens you press and hold bake and broil at the same time until SF comes up in the display. Then press bake, then use the arrow keys to raise or lower the temperature setting. If the temperature is more than 35 degrees off, you may have a bad sensor, bad control board, or other problem.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/jeffrey_634abadf963e31e5

Hello,

It does vary some by model yet the control can usually be calibratied by;

Pushing and holding the BAKE button until the tempature that is displayed changes to 00 then push the up/down arrows to adjust the temp. +/- up to 35 degrees once ya have selected the ajustment all be it up, or down 30 degrees push the cancel/off button and the change will be saved

One thing you should know about a gas oven is that they do not keep a constant tempature like an electric oven does. So going by a tempature gauge in the oven can fool you. The way a gas oven works is by "average" tempature. In other words if you take the highest and lowest tempature readings and average them out you will get the actual tempature. For example let's say that you set the oven to 350. Well first it will take about 10 to 15 minutes for the oven to properly pre-heat. Once it is preheated you can listen to the gas burner and watch a tempature gauge(flook meter is best). When the gas burner shuts off the oven tempature will continue to rise. When the oven tempature stops rising then you will take that reading. Then wait for the oven burner to come back on again and watch the tempature gauge. When the tempature gets to it's lowest point and stops then take that reading. Do this several times and then take all the tempature readings and add them together then divide that number by the number of readings you took and that will give you the actual tempature. Within 5 degrees is great but anything over 10 degrees can affect your cooking. This will give you an idea if your oven is out of calibration or not.

There is a calibration procedure. The instuctions are located in the owners manual and can be found here http://products.geappliances.com/MarketingObjectRetrieval/Dispatcher?RequestType=PDF&Name=49-85131.PDF

Just go to the "Thermostat Adjustment" section for the proper calibration procedure.

It does not sound like the guy is trying to rip you off. Most mechanical thermostats are adjustable by a center screw in the oven control knob stem behind the knob. The problem is when an oven is off by more than 30 degrees they become almost impossible to calibrate correctly and it is better to replace it. There would not be any danger in just using the thermometers and just living with the problem. It would be a very expensive fix for a Viking and if you can live with it then you are better off. The parts alone will probably be over $300 and then there is the labor charges. The thermostat assembly also includes the tempature probes so it requires major range dis-assembly to replace it. Sometimes the oven control knob will have an adjustment screw on the knob istelf(back of knob) to adjust the position of the dial ring to match the correct oven tempature. This can allow you to change the position of the knob to match the actual tempature of the oven. They usually will only go 30 degrees one way or the other though. So my advice is that if you can live with it and are able to still cook properly then put off fixing it. If you find that over time the cooking tempatures start increasing then you might have no choice but to have the thermostat assembly replaced.

Is this oven gas or electric? If it is gas then it can be normal to see 30 to 50 degrees difference in tempature. The tempature in a gas oven works on the average tempature. For example: The oven tempature may rise all the way up to 370 degrees. Then the burner will shut off. And then the tempature can drop all the way to 330 degrees. Then take 330 and add that to 370 then divide that number by two and the average tempature will be 350. If your oven is electric then the tempature should be much more consistant but can have a 10 to 15 degree variance. Also the standard oven tempature guage that you put in the oven or even the temp guage built into the oven are not very accurate. We us a Fluke meter with a thermocouple to calibrate an oven. So to check your oven for proper tempature regulation you will first need to let the oven pre-heat for about 15 minutes. Then place the thermocouple in the center of the oven. If the oven is electric the take a temp reading every 5 minutes and average them out. If the oven is gas then you will need to take a temp reading when the tempature reaches it's highest and lowest points. Take at least 5 consectutive readings and average them out. You should get an average within 10 degrees of set temp(350 degrees). If it is off by 35 degrees or less you can usually caluibrate the thermostat back to proper temp. This procedure can be different for each range model. If it is more than 35 degrees off or you are getting irratic readings then the thermostat or thermostat components might need to be replaced.

This is from page 13 of your manual:

To Adjust the Thermostat
Put the Oven Temperature knob in
the OFF position.
Press and hold the HOUR +/– pads for
5 seconds until the display changes.
Before display changes back, press
the HOUR +/– pads to increase or
decrease the temperature in 5
degree increments.
The oven temperature can be adjusted as
much as 35°F. or down as much as 35°F.
If the oven adjustment is set cooler
than the factory setting a minus sign (–)
and the adjusted temperature will appear
in the display.
Wait several seconds for the control
to automatically set and return to its
previous setting.

There is a calibration method to adjust the oven thermostat plus/minus 35 degrees if it is a digital display. The method varies depending on the model range. This calibration method is used to adjust the thermostat if it is not keeping proper tempature. For example if you are setting the oven to 350 and the actual temp it is keeping is 325 then you could use the calibration method to adjust it plus 25 degrees to correct the temp. Just so you know electric ovens will keep a pretty even temp but gas ovens will vary by 40 or more degrees to keep an "average" temp. For example the burner will come on when the oven is 330 degrees and turn off at 370. 330+370 then divide by 2=350. So a oven thermometer may not show you the temp you set it at in a gas oven but does not mean the oven temp is off.

You will need to check the oven calibration using a thermocouple based thermometer(the one you stick in the oven is not reliable). Electric ovens should keep a near constant tempature so if you have it set to 350 the oven should stay around 350 once temp is reached. Now gas ovens are a little different. Most use a on/off thermostat and that means the temp can vary from 320 degrees to 370 degrees to keep an average tempature of 350. So if it is a gas oven you will need to let it warm-up for 10 minutes then start taking the lowest and highest 5 consectutive readings. Then add the 5 reads together and then divide the number by 5 and it should be within 10 degrees of the set tempature. If it is off by more than 50 degrees then you might not be able to get it back to proper calibration. The calibration methods are different for each range and depend on the type of thermostat you have digital(push button controls) or manual(knob). The owner's manual for your range might contain the instructions or consult the manufacture's website for the instructions.

next to last page in your manual


Adjusting Oven Temperature
Oven temperature has been factory calibrated and tested. If
oven consistently over or under cooks food, adjust thermostat.
Oven temperature can be increased or decreased 35°F. To
avoid over adjusting oven, move temperature 5°F each time.
1. Push BAKE pad.
2. Press + pad until an oven temperature greater than 500°F
shows in display.
3. Immediately push and hold, approximately 5 seconds,
BAKE button until “00” appears.
4. Press + or - arrow pad to adjust oven temperature.
• To increase oven temperature (for a hotter oven), Press
pad until a positive number appears in display.
• To decrease oven temperature (for a cooler oven),
Press pad until a negative number appears in display.
5. Press OVEN CANCEL pad to save adjustment.
• Setting is saved if power fails or is disconnected.

heres a link to the entire manual if needed
http://shop.amana.com/assets/pdfs/literature/32103601.PDF