using a line-voltage thermostat to drive a blower

Hello,
does anybody have experience using a line-voltage thermostat to drive something other than a heater? I would like to use one to drive a 1/4 HP 115V electric motor, but I am concerned that it might not work. The specs for most of them (for instance, the Honeywell T4700) specify "resistive load only" and furthermore they have a minimum power requirement of 500W. I am afraid that the power supply of the thermostat itself relies on a certain amount of current flowing through the wire.
Thanks Luigi
P.S. What's the deal with alt.hvac? Is it exclusively for people who make a living out of HVAC installation/repair?
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These things work in series with the load. I assume the 500w minimum is a calculation about where you won't be powering a significant part of the load simply to drive the thermostat. It does sound high for any solid state device. Personally I think I would go with a low voltage thermostst and a relay/starter for the motor.
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Yup Greg
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Second that!
~kjpro~
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This is Turtle.
I think your tring to hook a light weight thermostat to a heavy weight electric load. I think you need to rethink this and go here.
For the price of a Honeywell T-4700 thermostat you can buy a Honeywell T-6031A-1029 and run a 1 horse motor and do fine. Or maybe a White Rogers 1609-105 which is the same thing in White Rogers. Also the starting amps of the 1/4 H.P. motor will be working on the T-4700 thermostat a good bite.
Now to your P.S. Question. We're Crazy / Somewhat but we would like to think that.
TURTLE
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From some of your other posts it sounds like you may have part of what could be a really nice system in place, I suggest you should get a hold of a contractor that specializes in industrial HVAC control systems and have him add contactors and some kind of a low voltage zonal control system.

Not exactly true, but for all practical purposes close enough........
== For example, if you wanted me to open up shop after hours and discuss modifications or fabricate repair parts on the cheap for your gyrocopter, wood chipper, dirt bike, ect. etc; then you had better at least bring along some good beer......
...BUT...
If theres 'any' doubt in my mind whatsoever you are wanting me to do something that may present a hazard yourself or others, I'm NOT gonna TOUCH it with a ten foot pole.....and at this point it dont matter how much cash you bring along, whether its during regular business hours or otherwise......
--

SVL



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Thank you for all the suggestions.
I have been using a contractor (Reid Heating and Energy in Marin County) for the major work, but it's not clear to me that the extra cost is justifiable for small, simple things that I can do myself almost as fast. Hydronics contractors are quite expensive. I figure I have being paying for labor at something like $200/hour. That's a fine pay for myself (no taxes either) and right now I have the extra time.
Using a 24V thermostat requires running 24V power to the switch, but it does seem like the cleanest solution. I'll have to cave in an break the walls. Only once I hope!
Thanks again.
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This is Turtle.
Running a line voltage to a thermostat in your home is dangerous to have 120 volts or 220 volt service hanging on a wall in your home. A kid can get up on a chair and pull the cover off and start playing with high voltage to kill him with. If you run a 24 volt system to control the pumps or water system it will be set up to do anything else you want later when changing things over to a new type system or control system. Set up a 24 volt control system is really simple to do.
TURTLE
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