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Old 04-06-2013, 03:27 AM   #16
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Flue Limit Switch removal safe?

What evidence is present as it's missing is this is a home warranty call, isn't it? Any tech with half a brain will deny you bypassing that safety switch. He was right from the beginning. Now look what you're doing to him, calling him out like this.

I'd of left you without heat.

What you don't understand is that we walk a fine line, that line being understanding your need for operation and what we can and will do about it. It's the inevitable backstabbing of home owners which is why we should leave you without heat and then once we find out the part is available but not on our immediate need which leaves us transparent, for you to do with us as you please.

If it were me, and I'm sure after this dysfunction with you, he'd as well know better than to trust a customer.

He should not have ever winked at you, he put himself on the line for your benefit. And when your benefit didn't work out as you saw fit you complained. That's what we get for feeling for you.


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Old 04-06-2013, 08:43 AM   #17
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Flue Limit Switch removal safe?

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Old 04-06-2013, 09:59 PM   #18
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Flue Limit Switch removal safe?

Doc Holliday,

Sorry to get you waving your pistols, but you may have misunderstood. I did make the "peanuts in a vise" comment because the last poster before my update had used that term for getting the service person or company in trouble. But even if the missing part is considered an integral safety device that should be there (which I honestly don't know yet), I would not be doing anything other than eventually letting the tech and his HVAC company know as a friendly FYI what the part turned out to be and how I replaced the functionality.

I promptly paid my bill, I did not complain to them in the least, and the little bit of follow-up to enlist their help to enable me to find out for myself what the part was, what it did, and if I can replace the functionality, has been completely congenial. (The tech took the fried part, had taken a photo of it, and had written down the numbers that were still readable on it, but unfortunately they weren't able to supply any of that info -- no doubt 'cuz, duh, the fried part was thrown away, the photo deleted, and the paper with the numbers recycled. And I'm sure all that happened only because the part was found to be not available, and they'd figured it wasn't necessary.)

The tech was a good guy and I wouldn't hurt somebody in that way (trying to get them in trouble with some bureaucratic monster). If somebody knew I'd used his/their services and asked for a recommendation, I would say that the guy is probably very very good 99% of the time, but on that particular day doing service for me he had a bad day. If they asked for more of an explanation, I'd fill them in on how it proceeded that first off he was at the disadvantage of working on an old furnace (it wasn't a warranty call, by the way), and due to him connecting some wires wrong from the outset, a 45 minute job turned into all day and an unneeded new "ignitor". And it did turn out that the point I was trying to make to him from the beginning (that the problem wasn't that it wasn't rectifying flame for the pilot light) did turn out to be correct. It would rectify pilot flame right away, and then the check of the electric piece which was bypassed incorrectly in terms of which wires were connected, was shutting it all down.

So the most "backstabbing" I'd do (in terms of saying something to a third party who knows who it is I'm referring to) is to present the truth of what happened in this one case, but that my sense is that the tech is a sharp guy who knows his stuff and usually does good work. Everybody makes a mistake at some point.

If I sound like I'm backstabbing the tech in this post (from which nobody would have a clue who he is or who he works for) it may be because so many comments by others here have focussed on it being wrong, and some sort of license-revoking thing, to bypass a required safety switch. But seriously, I wouldn't do anything to him or his company even if that turns out to be the case. And it is still unknown if that is the case.

I totally hope that the electronic part really is "optional", but via my very congenial follow-up with the HVAC company for assistance to determine that, they have not been able to find out what the part is that's now missing, and based on it being identified as "OPT" on the schematic, they are still of the mind that it is not a necessary safety device. And now I'm just trying to find out for sure.

I appreciated his not leaving me without heat and "caring" - as you say. And had he said, "Okay, I have to disconnect the wires now, and my guess is that part is a last ditch safety device to kick-in in case all others fail and there is a fire going on and the valve has not been shut off yet, so if you want to reconnect them you will have heat," I would have reconnected them. (Some in these forums will no doubt now say it's a miracle I'm alive!) He was supposed to get back to me in a couple weeks, but nobody ever did. He (or they, the HVAC company) should have contacted me and told me the part was not available and by their estimation it's safe to run my furnace. I don't think that's not "caring", but just, uh, not dotting an i or two...

My best to Wyatt Earp...

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Old 10-20-2013, 10:34 PM   #19
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Flue Limit Switch removal safe?

I believe that the part you have in the picture is a time delay control. TDC on your schematic. Mine burned up also (terrible smell) and the fan runs continuously. 60704a0-33 is the number on mine. I think it heats up when the gas valve comes on then makes contact to the blower. When the gas valve turns off, the heat keeps the TDC on which keeps the blower on until it cools and contact is broken. I could be wrong about that though. the important part is what to replace it with. Has anyone found a replacement that is a direct wire?
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Old 10-25-2013, 01:46 AM   #20
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Flue Limit Switch removal safe?

I believe you are correct about it being a "TDC", possibly also called a "sequencer" or "time delay relay". I had no luck finding out what my missing part was or what a replacement part would be going through York, so I took a shot at going to the original old HVAC company that had installed the furnace long long ago. That guy was very helpful, knew what it was (again, "sequencer" was what he said and his explanation of what it did made good sense at the time, though I can't say for sure it was exactly what you describe). And the guy did find a replacement.
I think the replacement is all about functioning at which volts and other hints in the numbers printed on the sequencer, and the replacement he found for me has "H1-20 C40 110 A1250" on it and looks to be this one:
As far as wiring, I did let them install (overall cost after the entire fiasco not much less than had I bought a new furnace, but... well, it's safe now), and the two red wires attach to the top/inside/silver prongs, and the two black wires to the bottom/outside/brass prongs. This matches someone's advice I find via a search for 60704a0-33, so I don't think it matters which red or black is on which side?)
Hope you get yours working again soon.
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Old 10-25-2013, 10:26 AM   #21
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Flue Limit Switch removal safe?

It is a timed on relay/sequencer to keep the fan running a bit longer and start it quicker as you have a reverse flow/counter flow furnace where the air goes down instead of up. the heat rises quickly up when the burner starts and they want the fan to start on a timer as well as the bi metal fan control.

Pictures are worth a thousand words and I could not solve it w/o that pic of the fan with the filters above it.


"Cut it twice and it is still too short".

Last edited by yuri; 10-25-2013 at 11:16 AM.
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