Shop heater advice

[Eric C Stoltzfus]

My shop is somewhat long and narrow, as I have said before on here. It is about a 15x40 foot single car garage. I have been wanting to heat my shop as it is getting cold here in pa. The building is pretty leaky, but I am trying to fix that. I am considering the Ceiling mounted workshop heater with 5,200 BTUs and 1500 watts. Is this a big enough heater for my shop?

[Jim Becker]

Eric, before I invested in my MiniSplit, I was using a ceiling mounted unit. (Fahrenheat) It produced good hot air and circulated it fairly well in my shop. Mine is the larger 30amp version and after the on-board "thermostat" (using that term lightly) bit the dust, I installed an external controller and normal wall thermostat. One of the nice things about them is that they can also maintain a very low (40ºF) minimum temperature to keep things reasonable overnight during the coldest times of the year. The only downside to these electric resistance heaters is cost to run. With your "bowling ally" shop configuration, you may need to use an intermediately located fan to help circulate the heat farther down the way.

[Andrew Seemann]

You will want to do a heat loss calculation for the area; there should be online calculators that are close enough. 5,200 BTUs isn't a lot of heat, especially in a leaky area. It will depend on the number of outside walls, the insulation, required temperature rise, etc, to find out what will get you the amount of heat you want.

[Jack Frederick]

In a well built and tight 600 sq ft building, I'd be okay with a 30k btu heater. With a "leaky" building you can easily get into multiples of that. Fix the leaks and bring the load down.

[Art Mann]

I can tell you that a 1500 watt heater of any kind will not be adequate for the coldest days in PA. It was not adequate for my old shop of similar size in AL and the climate there is much more mild. If your shop were well insulated, you might be able to sustain a temperature differential of 30 degrees or so, once the area is heated up by some other means. In my case, I used a 15,000 btu propane catalytic heater to bring my shop up to temperature.

[Andrew Seemann]

For perspective, the lights in the shop are probably putting out 2,000 - 3,000 BTUs.