Shop/Garage Heater

[RSKY]

I have planned for years to install a natural gas line to my shop and one of those ceiling mounted heaters. I also want a ceiling mounted heater in the garage. BUT, our local gas utility has very, very strict rules on who can install lines and appliances. This probably was caused by a couple of houses exploding a few years ago after the homeowners changed something on their lines. I know both of them. One of the guys told me he opened the door and flipped on the light switch and his next thought, before he passed out, was "Where is my house and why am I looking at the sky?". The other guy's wife was killed in the blast.

Anyway, the cost will be very high to have the gas line run from my house, around a patio, over field tile, under a sidewalk, and to the shop. The heater for the garage would be easy to install. Just run a line up the garage wall and mount the heater. So I am considering having a 240-volt ceiling mounted heater installed in both locations. I think it would take years for the higher cost of the electricity to overtake the cost of installing the gas lines and heaters. The garage heater would be set on 40 degrees and would help keep the utility room warm and the vehicles not as uncomfortable when starting out in them. The shop heater would be set just high enough to keep anything from freezing unless I ventured out there to work on something.

Does anybody have this? How much power is used? Are you satisfied with them? How about the sizing for the shop? It is a 24' x 30' insulated building with an upstairs that I intend to close off.

Thanks for your advice.

RSKY

 

[RNeumann]

Their are online calculators that will size the unit based on the climate zone, insulation levels of the building and size of the building. The calculator will give you a BTU amount. From there you can convert or size the electric heater based on BTUs.

 

[ovrszd]

Anxious to hear replies of experience.

Electric heaters have increased in efficiency. Curious to hear a realistic account of usage.

At your location I'd think the heating costs would be easy to swallow. Of course that statement doesn't apply today.......

 

[4570Man]

I have a gas heater in my shop and a electric heater in my garage. The gas heater is 70,000btu and the electric heater is 5,000 watt. I think it’s operation cost is about 60 cents an hour. They neither one see frequent use and I think you’re right that it would take a long time to to equal the higher installation cost. Pros to the gas heater. Cheaper to operate.
Warms the shop up faster.
Still doesn’t run without electricity but is easier to run off a generator.
Pros of electric.
Operates quieter.
Cheaper installation.

 

[shui5612]

I live in Canada and have two garages that are close to the size of yours: one is 28 x 32 by 13ft ceilings and the other is 24x29 by 10 ft ceilings.

The smaller garage has a 5000w (wall mount style that pushes air "forward") forced air Heater and the other has a 4500w forced air heater (wall mount) with a secondary 4500w ceiling mount heater ( blows air down).

Consumption wise they are EXPENSIVE. Even though electricity is 0.058$/kwh to 0.085$/kwh, they rack up on their own about 1-3$ a day in electricity with the garages closed and the equipment inside. If you take the things in and out of the garages then the consumption will increase. If you want more specific kw/month consumption and average air temperatures I can look it up for you. The walls are R30 and the ceiling around R50 in both garages.
The only downside is that say when you keep your garage at 5-10C or 40-50f and then you want to bump it up to 17c or 60-65f it takes HOURS.

This year I installed propane overhead heaters, one being a 40000 btu and the other being oversized at 200000BTU, and the time it takes to heat up the garage from 40f to 68f takes 15-20 minutes in one garage and 4 minutes in the other. Price wise propane is 2.50$/gallon in the summer and around 3.70$/gallon in the winter, despite this big cost difference I am saving $ (and time) unless propane reaches 4.50$/gal.

Maybe propane could be a cheaper alternative to natural gas? You'll save on plumbing but will have a slightly increased cost of running when compared to natural gas.

In brief, was I happy with electric heating? Yes, as long as you keep the temperature you want and use them to maintain that temperature. But if you're planning on working in the shop or garage and want to bump up the heat or will open the garage door to get the tractor/car in and out of the garage, you will need to pack almost twice the heating elements. Most calculators only calculate the required wattage to maintain the garage and not to heat it up after a big temperature difference.

For your garage size, depending on ceiling , insulation and how often you close /open the. Garage door I would put a 5000w wall mounted heater or a 4500w ceiling mount to maintain the temperature desired but you'll need atleast 2 more heaters of 5000w if you plan on bumping up the temperature when working.

Consumption wise figure one 5000w heater will work 10-12-14h a day to maintain the temperature (if it can even maintain it, sometimes they overheat and shut off, running close to 20h in a day) and two 4500s will work around 8h a day. Depending on the temperature difference and cfm. Multiply that by the rate that they charge per kw/h and you'll have a daily consumption.

Hope this helps

 

[KennyG]

Electric heaters have increased in efficiency. Curious to hear a realistic account of usage.

My guess is electric resistance heaters efficiency is exactly where it's always been - 100%. :laughing: In a moderate climate, the electric unit may be a good freeze protection option. For actually working, I would add a propane or diesel torpedo heater to quickly bring the temperature up. I think you would have to bump the electric heater up hours ahead to make it comfortable.

 

[ovrszd]

Good stuff shui.

It's my belief that if a garage/shop is going to be used daily, or even two or three times a week it's cheaper to keep it heated rather than try to raise the temp. Maybe a constant of 55-60F degrees for example.

I primarily heat with wood and backup with 70K propane furnace. I keep the thermostat set on 62F degrees. I stoke the wood stove the last time each day at 5-6p.m. Restoke at 8a.m. Last year I burned 115 gallons of propane. Doesn't take much for the propane furnace to maintain a warm shop.

Kind of a side track from the question at hand. But something to consider about maintaining an environment that can be used to work in.

Discard all my comments if all you are after is to keep a temp above freezing, say 40F degrees or so.

 

[plowhog]

My 3,600 sq ft garage is not yet completed, but the spec calls for four Qmark electric heaters. They are for freeze protection, not comfort heating. They will kick on at 40 degrees.

 

[ovrszd]

My guess is electric resistance heaters efficiency is exactly where it's always been - 100%. :laughing: In a moderate climate, the electric unit may be a good freeze protection option. For actually working, I would add a propane or diesel torpedo heater to quickly bring the temperature up. I think you would have to bump the electric heater up hours ahead to make it comfortable.

Yeah, after I said that I realized how stupid that was..... :ashamed:

What I meant to say is their design has improved and they can generate more heat from a kw than they used to. An example is those little Pure Eden heaters.

 

[ovrszd]

My 3,600 sq ft garage is not yet completed, but the spec calls for four Qmark electric heaters. They are for freeze protection, not comfort heating. They will kick on at 40 degrees.

This brings up another complexity.

If I were building a new shop my primary concern would be the efficiency of the building. If I nail that, my heat source becomes much less significant.

If I were modifying an existing structure to create a warm space I would apply the same principle. I'd insulate the snot out of it first, then consider heat source.