LB

Larry Blanchard

13/11/2007 4:58 PM

Semi-OT: shop heater

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?




This topic has 2 replies

Pp

Puckdropper

in reply to Larry Blanchard on 13/11/2007 4:58 PM

14/11/2007 1:58 AM

Larry Blanchard <[email protected]> wrote in
news:[email protected]:

> 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?
>

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
--
Wise is the man who attempts to answer his question before asking it.

To email me directly, send a message to puckdropper (at) fastmail.fm

Jl

John

in reply to Larry Blanchard on 13/11/2007 4:58 PM

13/11/2007 10:13 PM

On Tue, 13 Nov 2007 16:58:51 -0800, Larry Blanchard
<[email protected]> wrote:

>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?
>

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


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