my idiot electrician... (limit switch problem)

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j7art2

Minister of Fire
Oct 9, 2014
545
Northern, MI
So my electrician helped me get my wood furnace going a few months ago. He cleaned the chimney for me in early fall and gave me info, and after days of dialing in the limit switch perfectly, I finally got it working how I want it and I've been using it daily since.

I had him do some work for me over the weekend (went from 15A service to the barn to 100A! WOO HOO!) and he walked by the wood furnace and said "hey, you get this thing going yet?" Then immediately stuck his screwdriver into the limit switch and wound it before I could even respond to him. Now the dial sits too high, and it doesn't work right.

This is what it used to look like:

IMG_20141005_110030_407_zps4542648d.jpg



This is what it looks like now:

[
IMG_20141215_185929_536_zpsbcflihnp.jpg


As you can see, the dial is 'turned' significantly higher. This is causing all of my temperature settings to not work. The limit switch is supposed to tell the normal furnace when to kick on the furnace blower to pump air throughout the house and it doesn't. HOWEVER, if I take a screwdriver and force it back down to where it should be, it kicks on and functions like normal -- until I let up on it, and it springs back to the wrong place.

What are my options here? Can I bend it back, or am I forced to get a new one to the tune of $85?
 
Did he offer to replace it sense he was the one that broke it? I don't think you're going to be able to fix it enough to really trust the thing. I've replaced one on my furnace and when they go, they usually go. They're extremely fineky.

I think he owes you one.
 
No, he doesn't even know he broke it. Hes a 23 year old kid who barely lives above the poverty line and has had a really rough life. My parents were his parents landlords as a kid. His mom was severely schizophrenic and his dad is mildly mentally retarded. Hes a new journeyman electrician and is always looking for work, so I traded him $1500 worth of electrical work for $150, a truckload of box elder and a truckload and a half of ash. I also bought the materials. He doesn't have the money, even if I asked.

Right now it's set on manual mode, but it still doesn't seem 'right'.

How easy are they to replace?
 
No, he doesn't even know he broke it. Hes a 23 year old kid who barely lives above the poverty line and has had a really rough life. My parents were his parents landlords as a kid. His mom was severely schizophrenic and his dad is mildly mentally retarded. Hes a new journeyman electrician and is always looking for work, so I traded him $1500 worth of electrical work for $150, a truckload of box elder and a truckload and a half of ash. I also bought the materials. He doesn't have the money, even if I asked.

Right now it's set on manual mode, but it still doesn't seem 'right'.

How easy are they to replace?

I've been in your shoes and I definitely respect the way your handling this. I get it and I apologize if I came across a little too harsh. I understand the circumstances :)

I'm not sure just how easy it is but I've watched them being installed and it didn't take long at all. You might try searching YouTube for an install video and I always hate spending other people's money but I don't think you're going to feel quite right unless you have a new one installed, been there many times over!
 
I've tried bending it back, and it won't stay. Unless I take it off and force it, I don't think I'm going to have much luck. If I take it off, I may as well put another one on.

Since it took him a lot longer than he anticipated to do all the work, I offered to take my log splitter over there Saturday to split the rest of his large rounds that he had laying there. He also wants me to take down 5 trees and offered to split the wood with me 50/50. Red oak.

I think after that, I'll likely be all done with him. He's a good kid given the circumstances, but one thing I've noticed both with this job and another that he did for me earlier in the year was that he has very little regard to other people's property. He does a good job and everything is up to code, but he doesn't really take his time to make things neat and tidy, etc.
 
If you replace it yourself buy the exact model, take pictures of how it's wired before removing anything, kill the power at the breaker, then install. Set it to the manufacturers settings. On mine you are suppose to hold the dial to prevent it from turning then you adjust the tabs. Hope this helps a bit.
 
Are limit switches model specific? I was under the impression they were universal, similar to thermostats. If that's the case, I'm likely screwed. This thing is 40 years old, and Energy Mate is out of business. The ones sold at the local farm store though look identical. Honeywell limit switches.
 
I just suggested exact model for swapping simplicity. Another brand with the same electrical rating and same connections should work perfectly. Looking at mine it's a Honeywell and there's no way I'd pay someone to swap this out...If you've found one identical you're 99% there
 
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The one installed is a honeywell and the one i'd be installing is also a honeywell, so I think I'm golden there. Hopefully they haven't changed much in 40 years.

The only issue I'm seeing though is that apparently there are different lengths of limit switches. Maybe there's a standard length for most of them, and the other lengths are rarities. Without pulling mine out (and rendering at least my wood furnace useless and MAYBE even my normal furnace) there's no way for me to tell the length. I guess I could buy one, see if its an easy swap and the same length, and if not, pop it back in and run it on manual until I find one the proper length.
 
You can find them cheap online, and they are very easy to replace. Just make sure when the temperature is adjusted, the dial isn't rotated. It appears he rotated the dial when trying to adjust it, damaging the control.
 
He wasn't even trying to adjust it! It was already working. He just stuck his screwdriver in there to see if he could get the blower to turn on and verify it was working. (DON'T TINKER WITH STUFF RANDOMLY FOR NO REASON!)

ugh. I'm glad they're easy to replace. Is there a model number on them anywhere? I didn't notice one, but it's also dark down there.

On another note, nice choice in saws layness. lol
 
Duh, I didn't even see that lettering until you pointed it out. Thanks.
 
The word "control."

However, closer inspection shows numbers on the top of the box, above the dial in the pic. Black lettering.
 
Now the big question is, will the model number today be the same as it was 40 years ago?

I shall NOT be calling Honeywell customer service if I can help it to match numbers if they don't properly align. I recently had an incident with them in which I ended up writing them and calling demanding to speak to a manager a few days later and reporting the customer service guy that hung up the phone on me, refusing to help me with a thermostat install or give me any info on it. He left me stranded in a 47 degree house for nearly 2 hours before I just 'tried it' and ended up getting it correct.

Worst customer service I've ever dealt with in my entire life.
 
The ones like yours are all relatively the same, close enough to make work anyways.
After making a note of which wires go where you can just snip the wires or stick a small flat blade screwdriver in the small slot above the wire connection to release the wire, now remove the wire conduit from the switch body. Then you can remove the 3 or 4 screws holding the switch to the furnace, once the screws are all out you can pull the switch assembly straight out of the plenum, BTW, the heat sensing part that sticks inside will be ~6-16" long.
About the only variables I have noticed on the Honeywell limit switches are if it has a manual switch (the white push button) or not, and if the high limit temp is permanently set or adjustable.
Once you have the switch out and you can see how long it is, do like laynes said, go on fleabay or the like, you can buy new or used much cheaper than the local HVAC supply house. I bought a "used" one a few years back, it looked like new and only $20 delivered to my door.
 
The one at Family Farm and Home (similar to TSC) is L4064B2228, the one I have is L4064B2236. Are these compatible? I'd rather buy it in store than online if possible. I don't want to wait a week for shipping.

Trying to figure out the difference. Its getting cold again tomorrow. Manual mode will work in the mean time, but isn't ideal.
 
The major difference that I see is yours is has a 8" insertion depth and the TSC one is 5. I see no reason it shouldn't work fine
EDIT: Yup, I compared them side by side on Grainger, depth is the only difference, go for it.
 
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Look at your high setting, that's important if it has a forced draft or draft control. Some have a high limit of 200 degrees, while some are 250. Just make sure you can set the same temperature settings, on/off and limit if needed.
 
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Just curious as to what the depth does. I can order one on Amazon used in like new condition shipped overnight for $5 less than a new one in stores.

Provided it wasn't twisted...
 
Dunno on the depth/length. I have used different length switches on my own stuff in the past, seemed to operate exactly the same...I know, big help, right?! ::-)
 
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