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stubborn1 · 11-08-2009, 07:09 PM

Hi,

I need to replace the fan limit switch on my furnace. It's a Honeywell L4064Y1433. Searching the internet isn't helping me find an updated part number. My research is leading me to a L4064B2236. Am I correct in thinking that as long as I choose the right length and know how to read a wiring diagram that I should be okay? I'm looking at a lot of the current models available and don't see that much of a difference.

Plumber101 · 11-08-2009, 07:20 PM

Here's a link

http://www.myhvacparts.com/Catalogue...20Controls.htm

You can google "furnace parts fan limit" to find more. These are pretty common. By the number you provided it tell me you need an 8" one.

To verify measure the stem that goes into the furnace.

yuri · 11-08-2009, 07:26 PM

BE VERY VERY careful how it is wired. Some of them have a jumper between the fan and limit side of the new control which needs to be broken/removed or you will blast your low voltage side with 120 volts and do serious damage. Post a good closeup picture of the inside of the existing one and we can help.

stubborn1 · 11-09-2009, 01:07 PM

Quote:

Originally Posted by yuri

BE VERY VERY careful how it is wired. Some of them have a jumper between the fan and limit side of the new control which needs to be broken/removed or you will blast your low voltage side with 120 volts and do serious damage. Post a good closeup picture of the inside of the existing one and we can help.

Here is a link to my post from troubleshooting the switch which has a close-up photo. I'm at work right now and don't have access to the original file.

Fan limit switch help

Thanks for the help.

**beenthere** · 11-09-2009, 01:51 PM

Plumbers link, is not the fan limit you want.

The L4064B will not work right. And will cause you trouble with that furnace.

You may need to order it from a York dealer.

yuri · 11-09-2009, 01:52 PM

That is a "Timed-On" combo fan/limit control. Not just a basic 8" type. There should be no metal bar/jumper between the blue and orange wire terminals. I am sure those timed on type have no jumper. They are somewhat expensive. Try Johnstones/Grainger. May be up to $100.

hvaclover · 11-09-2009, 03:24 PM

Quote:

Originally Posted by yuri

That is a "Timed-On" combo fan/limit control. Not just a basic 8" type. There should be no metal bar/jumper between the blue and orange wire terminals. I am sure those timed on type have no jumper. They are somewhat expensive. Try Johnstones/Grainger. May be up to $100.

Stopped making them several years ago (so I was told by several wholesalers) but I found this

L4064W1098 HONEYWELL

More Details...

$102.22 Quantity:
This item usually ships: Same Day. HONEYWELL FAN AND LIMIT CONTROL 8" INSERTION. COMBINATION FAN AND LIMIT FURNACE CONTROL TIME ASSIST CLOSES FAN OPENS LIMIT CIRCUIT ON TEMP RISE. 200F STOP SET 50-200 FAN OFF. 100 TO 250F LIMIT RNG. INCL JUMPER. TRADELINE MODELS

luvheat · 12-12-2009, 04:55 AM

Quote:

Originally Posted by yuri

BE VERY VERY careful how it is wired. Some of them have a jumper between the fan and limit side of the new control which needs to be broken/removed or you will blast your low voltage side with 120 volts and do serious damage. Post a good closeup picture of the inside of the existing one and we can help.

sounds like my problem

luvheat · 12-12-2009, 04:59 AM

Quote:

Originally Posted by yuri

BE VERY VERY careful how it is wired. Some of them have a jumper between the fan and limit side of the new control which needs to be broken/removed or you will blast your low voltage side with 120 volts and do serious damage. Post a good closeup picture of the inside of the existing one and we can help.

I think this is the problem I am having on my fan limit switch

I have a Honeywell 8" fan limit switch

Is there any wiring diagram around we can see.

I see a diode jumper between the yellow and black wires on the opposite side of the fan/limit wires. Is that normal?