Semi-OT: shop heater

[Larry Blanchard]

I've got a small well insulated shop that I've heated for many winters using a portable 1500 watt electric heater. Each heater lasted 2 or 3 years and cost somewhere in the $15-$30 range. This year my old one died so I went shopping.

The first one wouldn't allow a temperature below 65F and I like to keep the shop at 40F or so at night. My mistake for not opening the box before I bought it.

I returned it and bought another. It ran up to the setpoint and then never came on again unless unplugged and restarted. Not viable.

Back to the store. This time I splurged on a $45 oscillating one with a shutoff timer and a "no-freeze" setting. Supposedly it would run to 5F over the setpoint, shut off, and come back on at the setpoint. I set it at 60F to check it. It ran to 65F, shut off, came back on at 55F and shut off at 62F. No telling what it would have done the 3rd time - I ran out of test time and patience. What a mess.

I'll call the manufacturer in the morning and see if I got a defective one. In the meantime, does anyone have a particular model that they've used and found reliable?

[Puckdropper]

Larry Blanchard wrote in news: [e-mail]:

I've had no trouble with a Holmes "legs" heater. I'm calling it that because if you turn it upside down it looks like a pair of legs. The lowest temperature is 65 degrees, but that's probably because most people want to keep their space livably warm, not just from freezing.

There's another option, though. You can get a plug in thermostat designed for pipe warp heating. It turns on at 45 or 50 degrees and turns off at about 55. Just set your heater on high and plug it in to the thermostat. I found the one I have at Menards. (I have not tried it yet, due to the offset nature of the device and the fact that the outlets in the shed don't have enough space around them.)

PUckdropper

[John]

My solution, installed in a small, well insulated building, was a little more complex. It used a radiant + fan forced heater (from Sears, vintage 1980) with an unmarked thermostat control, set (by experimentation) at 80 deg as an over temp shutoff. The temperature control was a standard wall mounted thermostat, powered by a 24 volt transformer and operating a relay (just like a standard house furnace) to turn the power to the heater on and off. The wall thermostat had an "off" position (move the lever to a temp lower than the detent) that set the thermostat to around 40 deg. The wiring (including transformer and relay) was in a metal box with a grounding cord (US,

120 volt, 3 wire) to the wall outlet and a standard receptacle for the heater.

When I planned to be in the shop, I pushed the thermostat up to a comfortable working temperature. When I left the shop, I turned the thermostat all the way down.

The entire assembly could have been removed with the only evidence of its existence being the holes where the thermostat was screwed to the wall. When I sold that house, the buyer wanted the shop heating arrangement left in place.

John