Help needed with Frigidaire RIS-39-56 Range

[kevin313]

This past weekend, I finally put into service a range that I rescued a few years ago, a 30-inch white Frigidaire range with wonderful French doors. The range was filthy - grease everywhere! Every evening for two weeks I cleaned a little section at a time, checked all the wires, replaced all the gaskets, light bulbs, etc.

I plugged it in and everything seemed to work (including the clock!) - but there are two issues:

1) One of the six inch burners will only work in "Hi" or "Simmer" - none of the middle settings will get it past luke warm. Is it the radiantube? Or is it the switch?

2) The oven (which does not have the original bottom bake element, but a replacement) runs about 50 degrees hotter than where you set the dial, and then when you open the door to take something out or check on something, the temp falls and doesn't come back up without increasing the temp setting. Any ideas?

If anyone has any info on this range or has any suggestions as to what I should check, I would greatly appreciate it!

 

[philr]

The front 6" burner is a "Speed Heat" on this model. Is it the one that's not OK? If it's the one, you'd have to check a few things. First, I'd suggest looking at the kind of switches that are used (and taking a picture of them) after removing the back panel to see if it's still got it's original switch. Looking at the burner connector to see if it's still a 2 wire burner. You could also read the resistance of the burners with an ohmmeter (with the range disconnected of course!). 

I'm not familiar with these 1956 ranges but if I remember well, 1956 Speed Heat burners are 2 wire 118V burners just like newer ones while the other 6" should be a 3 wire "5 heat".

The problem you describe seems to apply to a "5 heat" burner so it's probably the rear one or maybe someone messed something with the Speed Heat burner/switch/wiring!  The Speed Heat switch flashes the 118V burner for a few seconds at 236V to make it heat faster but then returns to 118V and cycles like a regular infinite switch. But it could have been replaced with the wrong type of switch... I think I have the 1956 Tech Talk manual for it, if you need some info from it, I'll try to send it to you later, just email me to the address in my profile! 

 

As for your oven, is the thermostat cycling normally once it reached it's (currently too hot) operating temperature or does the temp just drops too low before it kicks back on?  Maybe the contact points are dirty/sticking or there's something that doesn't move freely in it. Is this the type of thermostat that makes an audible "clunk" when the contacts close or open or the type that you can barely hear?

 

Can you make videos that show what happens?

 

[kevin313]

Hi Phil - thanks for all the information!

The 6 inch burner that is acting up is the REAR burner. From what I could tell when I was cleaning the range, all the switches seem to be original. I haven't looked at the burner connector, but I will and see if that gives me any clues.

The oven seems to reach it's operating temperature and then cycles off, as it should. I found that once I open the doors (letting the heat out of the oven) it doesn't cycle back up to operating temperature for some reason. The thermostat is very quiet - the signal light goes on/off with the cycle, but it barely makes any sound.

Next time I'm up at the cottage (where I have this range installed) I'll try to take a video of the situation.

Thanks again!

 

[kenmore71]

Kevin, I can say with certainty that the problem is not the radiantube itself or the wiring.  It has to be in the switch.  I can say this because HI uses both the inner and out elements of the radiantube as well as the return element.  If the tube is getting cherry red, both of the elements and the return are working properly and each is getting 240 volts.  The fact that SIMMER also works must be a fluke of the switch in that the contacts needed to produce that wiring scenario are also good.

 

In terms of functionality, any 5 position switch designed for the 3 wire monotube radiantube element will work electrically.  What I don't know is if ANY switch will fit physically since I don't know how many iterations there were of this type of switch over its 10 year run.  The three wire monotube radiantube with its 5 position switch was introduced in the RM series in 1949.  

 

Even after the introduction of the 2 wire radiantube in some of the 1955 models for the SPEED HEAT feature, the 3 wire element continued to be used on the early HEAT MINDER units and the rear burners of ranges with those feature through the 1957 model year and for ALL of the burners on mid and lower-end models through the 1959 model year.  In 1958 the 2 wire, 2600 watt, 8 inch radiantube was first used with the redesigned control circuitry and the Imperial models also got 2 wire radiantube units with infinite heat controls for the rear burners.  In 1960 all burners on all ranges became 2 wire radiantubes with infinite heat controls.  

[this post was last edited: 7/29/2013-18:07]

 

[philr]

Can anyone tell me what the "S" stands for in RIS-39-56? There's also a RIF-39-56., I don't know what the "F" stands for either. 

 

Kevin,

I thought I had the Tech Talk for this range but I don't. I have more stuff for the 1957 and early sixties models...

 

I do have a few parts books that show different part numbers for the same parts.  

 

Here are a few pics that I took with my cell phone of the parts manuals. Sorry for the quality. The first pic is for the oven thermostat, showing a newer part number, then some various pics from parts books. Strangely, some show 3 identical switches and no "Speed Heat" for this model while others do.  Maybe it was an error since the illustration clearly shows the speed heat switch. 

 

I do have a few used burner switches but none with the parts numbers shown. Some don't have part numbers anymore... If your switch happens to be the problem for the rear burner, take pictures of it and measure the shaft and I'll see if I can find something similar to replace it...

 

 

 

[kevin313]

Mark and Phil-

Thanks for the good information and the history!

Glad it isn't the radiantube, but I think it is easier to find a replacement than it is for a switch. I'll see what I can find online. The photos of the parts catalog is a BIG help!

Thanks again!!

 

[kenmore71]

Kevin, another option, if you needed that burner for other than HIGH and SIMMER would be to replace both the radiantube and the switch with a post 1960 2 wire element and infinite heat switch.  I know that this was done with the right front burner on my mother's 1958 RD-38 at some point around 1978 because the repairman claimed he couldn't get parts.