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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 7823
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have nineteen feet of electric baseboard heaters ran

Customer Question

Customer: I have nineteen feet of electric baseboard heaters ran through a thirty amp breaker using ten gauge wire. I've been using regular 22A thermostats and they don't shut off properly when the room reaches temperature. Would a 30 amp thermostata resolve this and, if so, where can I find such a thermostat? I've scoured the internet and all residential thermostats seem to be limited to 22A.
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Submitted: 1 year ago.
Category: HVAC
Expert:  Phil replied 1 year ago.


The 22 amp limit is because higher amperage, on a full time load would require #8 wire in most (but not all) applications, and that size wire is not compatible with wall mount thermostats.

You can how ever use a standard 24 volt thermostat, wired to control the coil on a 40 amp rated contactor that powers the baseboard.

Let me know if you want me to engineer that for you and provide a CAD drawing of the wiring diagram, along with materials list or not, That will take me longer than a simple question deposit covers however. I will submit an additional services request for that service, allow 3 hours.

Or I can give you a verbal description of such a layout for the amount you have offered,

Let me know, we can go from there.

Customer: replied 1 year ago.
This is pretty confusing to me. I have paid twenty eight dollars and really don't feel as though you've answered the questions as I was led to believe was going to happen. I'm not willing to spend any more money until I see something for the money already spent.
Expert:  Phil replied 1 year ago.

I will opt out so that other of our experts here can see your question.

Unfortunately some engineering will be required, and a CAD drawing, and parts specification, that will take 2 hours or so, so you may not get any takers.

Since there are not any 30 amp rated wall mount heat only thermostats, there is no simple answer. In that case I am opting out. Others here may have the answer you seek.

some design services will be required for a remote contactor conversion, that is the best solution that I personally am able to provide,

I hope that addresses your confusion. (the difference is between just a single answer, and an engineered solution)


Now here is the verbal description I promised you:

1. Mount a 24 volt transformer, and 40 amp contactor in a 10 x 10 x 4" electrical box near the source of power for the base boards.

2. Bypass the existing thermostat wiring by using wire nuts so that the base board gets power 24/7.

3. Then wire the contactor to interrupt that power, and control it with a 24volt thermostat mounted in the room with the baseboards.

I will opt out, so that you owe me nothing for that solution, let me know however if you want me to provide you with an engineered drawing and parts source specifications by accepting my offer.

Good luck with it,

Customer: replied 1 year ago.
OK. I just wasn't understanding the mechanics of the site. Probably didn't research that well enough but I think I now understand. You read the question and submit an offer to me to resolve the problem. Explain exactly what I'm getting now for the thirty bucks and I may very well be interested. I'm mechanical enough to get a rough grasp on what you're saying. Sounds like, in essence, it's creating a relay in the 240 circuit triggered by the 24 volt thermostat. Also, is my twenty eight bucks gone? In the original submission it said something about a five dollar deposit but then charged me twenty eight. It's not a huge amount of money and isn't going to make or break the deal. I'm just wanting to understand how this works.
Expert:  Phil replied 1 year ago.

Hello again, your understanding of the 40 amp contactor solution is accurate,

Customer: replied 1 year ago.
Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
Customer: replied 1 year ago.
Not sure what I just did. I thought I was setting up a phone link to you. Anyway, Phil, I'm in. Tell me what I need to do to get the drawing and the material list. And thanks for the time already invested.
Expert:  Phil replied 1 year ago.

Hello again,

Just accept the additional services offer you already have from me, I will begin working on your drawing and specifications in the morning

I need a photo of the breaker panel in which the breaker switch for the 19 feet of baseboards resides showing the panel and 3 feet around it in all directions. Use the paper clip icon at the right end of the tool bar above to attach the photo

A phone call is included in the additional services offer.

Customer: replied 1 year ago.
I'm just not seeing something here Phil. Sorry to keep bugging you. I want to accept your offer but there is nothing in any of our correspondence that tells me how to go about accepting the offer or how to send you the photo. Getting late now. If you haven't given up on me maybe tomorrow we can figure out how I'm to accept your offer.
Customer: replied 1 year ago.
It may be because you referred me to another tech?
Expert:  Phil replied 1 year ago.

I submitted the issue to management, the site software would not let me submit a duplicate additional services offer,

Customer: replied 1 year ago.
OK. Just wait for them I guess. Thanks for bearing with me Phil.

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