Frigidaire Touch and Cook Range

[frigilux]

I babysat the kids of the local Frigidaire dealer when I was in junior high/high school. They switched out appliances regularly and everything was top-of-the-line. I flipped out when I first saw and used their Touch 'N' Cook; it was so futuristic. In fact, it may be the reason I prefer electronic controls on appliances.

Their washer with the infinitely-variable pulsate and spin speeds was another big hit with me. No wonder I had such a virulent case of Frigidaire envy, LOL.

 

[philr]

Thanks Robert for moving this thread.

 

Tonight I removed the back of the range to see how it looked like, The circuit board has been replaced by a "Series II" which is dated 1975. That's what I expected because the oven sensor is the newer, shorter type that matched with this circuit board.  There was an issue with the right front burner that would turn on full heat anytime I turned on another burner (or this one) and I didn't quite understand that. I had no multimeter with me but I removed the thermal relay that was supposed to be the one related to this burner and everything seemed fine inside, the contacts weren't damaged or sticking.

 

After I reassembled it, the problem was gone.  I completely forgot to take a picture of the back of the range but I took some of the wiring diagram. I'll study that tomorrow! 

 

Anyone can explain me how this works? I don't understand why they use this kind of relay (which looks like a much simplified Robertshaw infinite swicth with just 3 terminals, a single set of contacts and a heater around a be-metal inside and of course, no adjusting knob) rather than magnetic relays.

 

I thought that the surface units were just cycling with a timed sequence from the circuit board. I need to read better the documents I have pictured!

I can see a common thermal relay for the two large burners on the schematic but unless I misread something, it's not for the 4 burners (which is what I would have expected). I'll have to remove the back cover and study that this weekend. 

 

Are the two small burners 118 V and the two large ones 236V? That would explain why no common relay for them?  Then I guess there might be something going wrong with the circuit board as if I pressed on any of the burner controls and left the number 0 on the display window, the right front burner would come on full heat.

 

Also, I haven't tried the timed outlet but I think it's strange that it's also controlled by a thermal relay (which looks normally closed rather than normally open on the schematics). Do these relays have a continuous duty cycle? I mean, setting the timer on would heat the bi-metal strips for up to 12 hours to open the contacts until it's ready to start? That also means having a short power failure early at night would result in having coffee done much too early rather than not done at all or done later as with a regular mechanical timer! 

 

I can see why these ranges were never modified to meet the Canadian standards of that time! I guess they would have required a lot of modifications!

 

 

[henene4]

That range actually has some basic matches UI wise to some cook-tops sold here in Germany.
Electrolux as well as BSH (Bosch&#92Siemens) have a version of their UI where you first press the button for the corresponding burner and then hit the number of the cooking-power you want. Though, they mostly sell these models only as induction versions.

On the topic of power levels: Our first induction unit (Siemens, controlled by knobs) had 18 powerlevels: 1-9 in half steps (displayed as 1, 1. , 2, 2. etc. and a power mode). Which was really nice. With our new E-Lux build IKEA unit and only 10 levels (1-9 plus power mode on 2 of the 4 zones), anytime I cook some pasta, 6 keeps it boiling to strong, while 5 only boils periodicly. The Siemens one held perfect boiling without boiling over on 5. level. (Side note: as usual for induction, on lower levels both models cycle on and off and both had the change to steady heat at 6).

Back on that model:
I personaly love the look of it. Realy modern, yet somehow strangly datable.
The ofen looks quite good size as well.
That wiring diagram really shows off the complexity of this bit of technology.

Question though: As far as I can tell, it uses no extra sensor or guide system for self clean, so it regulates using the standard temperature sensor and the main board for timeing of the heating cycles and temperature control, or am I wrong?
And is there some kind of catalyst for fumes&#92smoke?

 

[philr]

No extra sensor...

That seems right.

My 1967 Frigidaire self-cleaning range has two different sensors. One for baking and the other for the cleaning function. This one has only one sensor for both. I haven't looked closely at the oven vent but it should have a catalyst. The vent is routed at the back of the oven and there's a screen with an opening below the right side of the control panel.

 

[henene4]

Thanks for that info!

 

[jetcone]

PHil

does it have the varistors installed? They are key to protecting the electronics.

The 'PC= "power control"? board must set the thermal relays somehow. 0-9 determine the cut off limit through the relay. So the relay has to send electronic information from the burner back to the PC board. The board must have to match the info from the relay i.e. there must be a NAND gate in the PC board. Setting 9 , if 9 then NO so that cuts the power off to the burner. Setting 9 , if 8 then YES keep the power on till setting matches 9.

 

Thats my guess.

Yeah, those black triangles are connectors to a logic circuit. And the connect to the relays that control power to the burners. I can't quite read the diagram but it looks like relays for  RF and LR connect between 220 volts. Are they the larger burners? It looks like all 4  have a common thermal relay. One side regulates 110 through two burners the other regulates 220 through the other two.

 

 

[philr]

Thanks Jon,

I'm not too good at reading this and I don't have all the service information either. I also might be wrong but I don't think that Frigidaire had any service information for the board itself anyway.

The varistors are there too. I noticed there's a trace of something that went wrong in the centre of the back panel but I couldn't see anything that would have caused that. That was probably caused by a previous failure that was repaired a long time ago!

The other thing I noticed is that some traces at the back of the circuit board had attracted metallic particles like a magnet.

 

[philr]

I tried the range again tonight and everything was fine. Still, I think I'd be interested in getting some of your spare parts John just in case something goes wrong again! I saw the adjustment potentiometers for the oven temperature at the back of the circuit board. One is clearly identified for the bake but I haven't touched it. How important is it to adjust these with a non-metallic screwdriver?? 

 

[jetcone]

Very important to

only use a non metallic screwdriver!!! And these "Pots" will be old so they will probably do a wide swing when you turn them only slightly.

For stereos people spray them with Caigs Gold  and then gently work them back and forth 10-15 times before putting back to where they were and then adjusting them.

 

Non metallic screwdrivers are available at any good Radio Shack. I think I've even seen them at Lowes'. You might try Canadian Tire too.

 

And only use the tiniest bit of Caigs Gold, I mean teenie !!

http://store.caig.com/s.nl/sc.2/category.292/.f