Frigidaire 40 inch range model #REG46NW-2

Check the alignment to see is the door makes a complete closure. If the door sets perfectly, check the hinges on both sides to see if they are tight and make proper connection with the oven opening. I doubt if the door seals using a Magnetic strip, it generally hold fast by spring pressure.

The first thing I'd suspect is a poorly fitting door seal / gasket. This will permit the heat inside the oven to escape. Check to be sure the the one installed is defective (cut, split, frayed, dislodged, etc.) Replacement parts:
http://www.appliancepartspros.com/whirlpool-gasket-door-w10074200-ap3892420.html

Make sure this is the part you need before ordering.

there's a door gasket that seals it not the metal part of the door so you might be able to stick your thumb in there as long as the seal on the door is closing tightly to the frame,when you open the door it should be on a 90 degree angle,before you had new hinges put on the door, most likely the door sagged lower to the floor and didn't close properly,if you think alot of heat is escaping you could have a bad door gasket.so open the door,look at it from the side,it should look like an L or at a 90 degree angle or even up a little,if it is the hinges aren't the problem if you think to much heat is escaping,call whoever did the work for you and have them check the door seal or gasket same thing.you didn't send the model number so i don't know what seal you need,go here and watch video should be similar and you can put your model number in to find correct part
http://www.appliancepartspros.com/whirlpool-gasket-oven-door-wpw10162384-ap6016005.html
hope this helps you out,if heat is coming out with door closed and you have new hinges this is most likely what's wrong

This sounds like a problem with the oven thermostat. If a slow heating problem is reported the element can be the problem sometimes but generally it would be the thermostat which has complete control over the elements heating cycles. It sounds like you may need the thermostat replaced. I hope the the oven door seal it tight. This can cause problems if too much heat escapes through a faulty seal.

Hello- Check these things first-  Door seals tend to get stiff over time. This is normal. Door hinges can become loose or get bent a bit, causing door to not close tight. This little gap can allow heat to escape, causing extended pre-heat times and frequent cycling of elements. If door doesn't seem to pull shut tightly- hinges will need to be replaced. If oven appears to operate normally otherwise, this should solve problem.  Let me know if the info helps- have more if needed- Thanks  - Ed

Unfortunately, dishwasher generate a lot of heat and water vapor. Some manufactures are now including a pressure sensitive mylar / aluminum strip to be attached above the door under the counter to prevent water vapor and or heat damage to wood or composition wood counter tops. However if water vapor is seeping out from the side of the door and causing damage to the adjacent cabinets woodwaork, the dishwasher door gasket may be faulty. Since this might be the problem, it would appear that your dishwasher is used a lot or getting old. New gasket is about $20. If the door closes and there appears to be a lot of play in the closed door,the latch may be in need of adjusting if possible. That is, even thought closed and operational, the seal is not tight and the dishwasher is running without having a tight seal on the sides. If you have a stone counter top, any water vapor / heat escaping from the top would not be apparent since stone is not damaged by the heat or water vapor, but the adjacent wood cabinets are.

Sounds like the oven door hinges have worn. If door is not obstructed in any way and will fully close when pushed but open about half a inch when released then it will be the hinges. Not sure of cost of spairs. I believe this to be a John Lewis Model. If it has a Enr no inside the door or inbetween the door hinges then I could give you price on spares

Normally you should have an appliance spare parts supplier in your area. They generally stock all range of spares for all appliances. You need to pull plug out of the wall and remove the panel covering the wiring to gain access to the oven thermostat. Look carefully on the body of the thermostat and record any numbers you see on a sticker that's present. Then remove knob off in front of thermostat and see if there is a nut attached to the centre which holds the thermostat in position or if there are 2 screws holding the thermostat in place. Use this information to order the thermostat also quoting the oven model number.

THEY NEVER SIT REAL TIGHT,BUT SOME CAN.TAKE A TEMPERATURE (SAY 250)AND SEE IF IT HOLDS.THE IDEA IS TO SEE IF YOUR LOSING HEAT OR JUST BAKE SOMETHING TO SEE IF IT IS UNDERCOOKED.YOU CAN CHANGE THE HINGE IF YOU WANT TO BUT I DONT THINK IT IS NEEDED.

The same thing with mine. I took apart the door today and found the hinges a little bent. I think it should be ok to bent them the opposite way a little with some mole grips......and then I must remember not to move the stove out for cleaning by the oven door handle again (oops).
Door comes off (unlock hinges and lift up). undo 4 screws on the bottom edge and then two on the inside of the door handle then it comes apart - beware as it's heavy. The hinges themselves come off with two screw each.