Novak Conversions Jeep Wrangler TJ engine mounts

Heating Garage

I have a 25' x 30' garage with 14' ceilings. No insulation except for the roof which is TPU over 4-8" of foam (8" close to house about 4" as you get away for drainage, probably averages out to R30 insulation). My garage door is really leaky. The last week with the temps as low as 22 overnight, the temperature in the garage never got below 47. I was doing paint and body work and I also don't like being cold, so I wanted to get it into the high 50s or low 60s.

Last week I added this heater since I already had 220 in the garage for my table saw and band saw: https://www.amazon.com/dp/B009NJ6K8K?tag=wranglerorg-20

It worked well, raising the temp about 4 degrees per hour according to a temperature/humidity gauge I can monitor remotely and graph. To me it felt warmer than that.

I did some paint and body work all last week and the paint had no issues with the temperature range the heater provided. It was a very dry heat too since it was electric with the humidity staying in the 30s even when I was etching, wet sanding, and cleaning/degreasing. I'm sure it was expensive to run, using 5600W, but I only ran it 2-4 hours a day. It worked well even when I had the garage door raised about 30" with a fan blowing out to clear the paint fumes.

Over the weekend I added this smart 220v pool switch https://www.amazon.com/dp/B0CZP682FR?tag=wranglerorg-20 so I could have the heater start running about an hour before I go in the garage each morning (I usually spend 430am -6am in the garage before getting ready for work). I used this extension cord https://www.amazon.com/dp/B0DHZVQ7D2?tag=wranglerorg-20 as the leads for each end into the smart switch. I have about 5' going from the switch to the receptacle and the other 20' so I can place the heater wherever I want to in the garage. I think the wire in the extension is undersized a bit for a 30A 25' extension as it is thinner than the 30A extension I have for my RV. It's 12AWG stranded... I think it is a little under 12AWG in reality and the RV extension is 10AWG. The line running from the main panel to the garage sub panel is 8 or 6 AWG. Anyway, the combination seems to work well and while the extension is warmer than room temperature by a good 10 degrees, it is not hot anywhere that would cause concern.

I think I spent a total of $250 on everything.
 
Mini splits are great so long as you can afford the install cost and it doesn't get too cold in your area.
They are half the cost of propane to run in my area.

Word of warning. If you don't get mitsubishi or fujitsu it's a crap shoot on how long it will last or if parts and service will be available.

I won't warranty or work on the dozen or so Chinese brands after the fact if a customer already has one and needs it installed.daiken,midea,mr cool,etc. They are garbage

Surprised to see Daiken on that list....they've been in the heat exchanger game a long time...I have quite a few of them in my shop to cool coolant or oil for my machines.
 
Mini splits are great so long as you can afford the install cost and it doesn't get too cold in your area.

OP is just a little south of me, maybe a two hour drive. Our average winter temps December-March are in the 50s. We usually have a few weeks of arctic blast here and there throughout the winter where daytime temps will be around freezing and nighttime in the teens, but that doesn't last long. Every February, we see at least a few days in the mid 70s. Heat pumps are the norm around here and mini-splits are becoming quite popular.
 
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What the hell is that three mile long link? Good God
It’s a gift I have with technology….i can futz up about anything…

IMG_4742.jpeg
 
Question... when looking to find the sq ft of a 2 door garage (insulated walls & doors) wouldn't you use ceiling height also for BTU's ? In my case... 22' x 21' x 10' = 4620 sq ft . Using 4620 sq ft x 20 (BTU #) = 92,400 BTU's needed. Is this correct or just use the ground measurement of 22' x20' ? Looks like I could heat or cool a full size dairy farm barn with the unit needed when height added. Dam... this Jeep is getting expensive... could of got a fairly new 911 Turbo Porsche and saved some money.
 
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Yeah, but then you'd have to fight off all those chicks! :ROFLMAO:

Got that area covered pretty well even if I did have a Porsche... I dress like the homeless and keep my old looking wallet very thin. The ladies don't give me a second look.
 
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You guys with electric heat be aware that electric space heating circuits are supposed to be sized at a minimum of 125% of the load.
 
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Surprised to see Daiken on that list....they've been in the heat exchanger game a long time...I have quite a few of them in my shop to cool coolant or oil for my machines.

I don't know how many types of products have the daiken name.Or if quarterly profits made them sell out at some point like everyone else, but their heat pumps are made in the same chinese mega factories as cheaper brands. They do try to have tech support and parts but it falls well short of acceptable for either me or customers. "Try a new board for 400$" doesn't fly when trying to diagnose issues. Especially when that cost is on you.

There is a place for the cheaper units.if you are ok with them lasting 5 years can't afford 5-10-20k$ for the 20 year lifespan stuff then go for it
 
Question... when looking to find the sq ft of a 2 door garage (insulated walls & doors) wouldn't you use ceiling height also for BTU's ? In my case... 22' x 21' x 10' = 4620 sq ft . Using 4620 sq ft x 20 (BTU #) = 92,400 BTU's needed. Is this correct or just use the ground measurement of 22' x20' ?
I've been retired a few years, but when I was working, heat loss calculations for residential was simply square feet. I'm guessing there aren't too many residential structures with 14' ceilings.

Commercial calcs took into consideration a lot more. Things like your latitude, time of day, east or west facing, window area, window type, and dozens of other things.
 
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Before I added my electric heater I was using a 210,000 BTU kerosene/diesel torpedo heater. It heated up quickly but sounded like I was filming Top Gun in the garage and I figured it was only a matter of time before I burned something that I didn’t want burnt with it.
 
The one thing I'd change about my setup is going to a Bluetooth thermostat. Then I can preheat the garage to "Mexico hot" before I even go out there. As it is, it only takes 10 minutes to come up to 70°.
 
If I ever build my own shop I think I’ll do a heated slab. Nothing like a 60° shop and laying on a 40° slab under the Jeep.

Heated slabs are the bomb and I don't understand why more homes and garages don't have it. We have wood floors and a crawlspace and I've always wanted to put radiant floor heat under the wood, clean, quiet and no dry air in your sinuses.
 
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Heated slabs are the bomb and I don't understand why more homes and garages don't have it. We have wood floors and a crawlspace and I've always wanted to put radiant floor heat under the wood, clean, quiet and no dry air in your sinuses.

They're the bomb until you get your first utility bill. They are very expensive to operate whether it's electric or hot water.
 
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They're the bomb until you get your first utility bill. They are very expensive to operate whether it's electric or hot water.

I’ve got a heated slab in my 42x30 shop and put in a mini split after a couple of winters. My propane use was off the charts. Now I pay about $60 a month in electricity for air conditioning or heat in the shop.

I use the slab heat only in the coldest days but the mini split can still make heat when the temperature is in the teens.

That warm floor is nice though.
 
Novak Conversions Jeep Wrangler TJ engine mounts