Cold Weather Coming...garage Heater

[landar]

A little off-topic but...I hate freezing my toosh in the winter time working in the garage. So, I usually just delay auto work unless forced. I am thankful for a garage in which to work but would really love to have a decent heater out there.

So, I have been doing a little research and found 3 types that might work. My garage is a three car, approx. 900 sq ft.

1) Electric heater. Since I have 240Vac in the garage at several locations, I could use one of those big 5kW jobbies. The nice aspect of the electric is that I could move it around to where I am located. Although that sounds like a lot, it is actually only about 17-18k BTU/hr (which ain't great).

2) A "Hot Dawg" natural gas conventional heater with fan. Lots of heat...75k BTU/hr. Now we're cookin with gas!

3) A radiant, infrared natural gas heater. Intially more $$ but supposed to be more comfortable.

Anyone ever install a heater? I would appreciate advice as I seek to determine if I buy a heater. I am pretty sure I can sell the "Frau" on this idea.

[LEXIRX330]

Be a man put on a sweatshirt and grab a beer! :) my garage actually stays pretty warm have you insualted your garage door or doors? Loads of heat is lost there also fill cracks around the garage door too!

[landar]

Be a man put on a sweatshirt and grab a beer! :) my garage actually stays pretty warm have you insualted your garage door or doors? Loads of heat is lost there also fill cracks around the garage door too!

Believe me, I always grab a beer when working on the Lex ...hey, wait a minute...that might explain all the half-tightened bolts.

You are absolutely right. I can do w/o the heater. I have for the last 15 years. But I really wanna turn my garage into a man-cave. Gotta have a heater. Got a fridge out there already.

The garage doors are insulated.

Now, if'n I lived in balmy MD, I would not need a heater!

[curiousB]

I put in a vent (ventless) free gas heater a few years ago and ended up taking it out. I hated it. The byproducts of combustion of natural gas are mostly water. As a result ventless heaters raise humidity of a cold space significantly. This contributes to rust (cars, tools,…) and frozen door jams and the like. My main reason to get rid of it was I thought it made me sick. The design of all these vent free heaters is supposed to minimize CO emissions but I don’t believe it. I swear I didn’t feel well after being in the garage for a few hours.

I replaced the heater with a Mr. Heater vented gas unit. It’s the very similar to the HotDawg you mentioned. I put in a 45k BTU unit in a three car garage and it works well (they recommend 75k BTU for 3 car, but my garage is all insulated and a heated room above). I couldn’t be happier. No more odd combustion odors. No elevated humidity. Thermostat driven heating (on a wall mount thermostat away from heater) to ensure whole garage is warm. These guys are very smart with electronics to control the electronic ignition cycle and blower motors, features you see in higher end furnaces.

I went with a vertical gas vent (Vent B pipe) through roof but the beauty of these units is they are power driven exhaust so you can vent out the wall horizontally. My neighbor has the same thing and he vented horizontal, I vented vertical. We're both happy.

I’d spend the extra money for an externally vented gas heater if you can swing it. They are the cheaper to operate vs electric (lower $/BTU) and only slightly more expensive for the unit. An electric heater will require some beefy branch circuit wiring back to your panel so don't forget to add that to the cost equation for electric.

I did the installation myself and lived to tell the story. Nat Gas isn't that difficult to work with.

[LEXIRX330]

Believe me, I always grab a beer when working on the Lex ...hey, wait a minute...that might explain all the half-tightened bolts.

You are absolutely right. I can do w/o the heater. I have for the last 15 years. But I really wanna turn my garage into a man-cave. Gotta have a heater. Got a fridge out there already.

The garage doors are insulated.

Now, if'n I lived in balmy MD, I would not need a heater!

Get one of these it will keep you warm!

Sorry can't attach the pic! It was of a kegerator! :)

Edited November 22, 2010 by LEXIRX330

[billydpowell]

Heater??? move down here in Texas, you can easily put a AC unit in your garage for the summer.

[landar]

Just the kind of feedback I was looking for, CuriousB. I am very leery of the ventless stuff. I also don't want one of those kerosene "jet" heaters. They make me sick and they stink.

I saw a 75 kBTU Mr. Heater at Lowes today for $487. Tempting.

However, I am still kicking the infrared idea around. Maybe a tube/reflector that runs the width of my garage and is mounted at the back ceiling angled down at 45 degrees.

But way more money (2x) initially and probably not worth it.

I put in a 40A subpanel with 6 ga. wire when I built my 3rd car stall a few years ago. But I know the 5kw of a 240v heater is no match for the winters here. I would need to go with a 3 phase heater and about 56A to be effective. Not going to happen. N. gas is too cheap to pass up.

Thanks again for the advice.

[landar]

Heater??? move down here in Texas, you can easily put a AC unit in your garage for the summer.

Billy, good idea. I am saving Texas for retirement living though. Still have a few years to go. Save me a spot.

[pj8708]

Just the kind of feedback I was looking for, CuriousB. I am very leery of the ventless stuff. I also don't want one of those kerosene "jet" heaters. They make me sick and they stink.

I saw a 75 kBTU Mr. Heater at Lowes today for $487. Tempting.

However, I am still kicking the infrared idea around. Maybe a tube/reflector that runs the width of my garage and is mounted at the back ceiling angled down at 45 degrees.

But way more money (2x) initially and probably not worth it.

I put in a 40A subpanel with 6 ga. wire when I built my 3rd car stall a few years ago. But I know the 5kw of a 240v heater is no match for the winters here. I would need to go with a 3 phase heater and about 56A to be effective. Not going to happen. N. gas is too cheap to pass up.

Thanks again for the advice.

Just an add on; my father-in-law has a large garage, holds a double cab pick-up; van; 35 ft. camper & wood working shop. Heats all in winter with LP heater hung from cieling and vented outdoors. At 10 degrees out side it is a toasty 68 inside.

Paul

[dasha1]

Be a man put on a sweatshirt and grab a beer! :) my garage actually stays pretty warm have you insualted your garage door or doors? Loads of heat is lost there also fill cracks around the garage door too!

Believe me, I always grab a beer when working on the Lex ...hey, wait a minute...that might explain all the half-tightened bolts.

You are absolutely right. I can do w/o the heater. I have for the last 15 years. But I really wanna turn my garage into a man-cave. Gotta have a heater. Got a fridge out there already.

The garage doors are insulated.

Now, if'n I lived in balmy MD, I would not need a heater!

I do believe it can be quite warm in the eastern shore of MD. I always wondered why in 1991 then governor William Donald Schaefer compared the Eastern shore to an outhouse. I've never been there, but the comment always struck me as unfair and unbecoming of a governor.

[curiousB]

I put in a 40A subpanel with 6 ga. wire when I built my 3rd car stall a few years ago. But I know the 5kw of a 240v heater is no match for the winters here. I would need to go with a 3 phase heater and about 56A to be effective. Not going to happen. N. gas is too cheap to pass up.

5kW is about 17k BTU so you'd need about 13.2kW to get 45k btu (which will require a 60A @240 branch circuit and 6 AWG wire) or 22kW to get 75k BTU (90A branch circuit and 3 AWG wire, so not really feasible in single phase power). 3 phase isn't an option in most residential areas as the utilities tend to only offer that to commercial customers. Even if you could get it you be subject to extra transformer fees and peak demand surcharges.

So you can see to get equivalent BTU to gas you need major current draw which implies a big branch circuit, contactor to switch load, thermostat to control contactor, heavy branch wiring, big breaker, likely EMT conduit, and enough free capacity in main panel to feed load. Electric is no piicnic at these power levels. I'd go vented gas like the hotdawg. Infrared vs forced air isn't such a big deal. All you want the heater to do is to raise garage temp in a reasonable period of time on the coldest days. I can get from 10 degrees to 68 in a little over 1 hour of heating with 45k BTU.

If you really want electric here is a 1phase 240V 10kW unit. Its $750 without accessories.

http://www.shophmac.com/electromode-euh10b34ct.html

[landar]

The electric is out unless I want a little extra spot heating in the garage. The vented gas is looking pretty good. I can get a 45k BTU Mr. Heater at Lowes for $377. Or a 75k unit for about $100 more. However, the 75k unit might cycle on/off a lot more often once up to temp (I only need 55 F in the garage to work). So, I am leaning towards the 45k unit. The 75k unit is a better price on a BTU per dollar basis but over-sizing is a common heating mistake.

Also wondering about the construction/quality differences between Mr. Heater and Modine Hot Dawg. Modine is a little more but might be worth the extra $ for quality, part availability. Then again, maybe not.

The really good news is that I passed the idea by my wife this morning and she gave me a tacit "ok" for the heater.

[LEXIRX330]

The really good news is that I passed the idea by my wife this morning and she gave me a tacit "ok" for the heater.

Well it is good that you got the approval of the "boss" :)

This is what I tried to attach yesterday! (I didn't ask before I got it) But I did not get in to much trouble...

BEER.bmp

[curiousB]

Also wondering about the construction/quality differences between Mr. Heater and Modine Hot Dawg. Modine is a little more but might be worth the extra $ for quality, part availability. Then again, maybe not.

I think the Mr Heater and the HotDawg are from the same manufacturer just branded differently. Modine is a bigger name and I suspect slightly better quality. They do a lot of commercial heaters you see in service bays and warehouses.

It depends on how much you use it. I just turn on the heat the days I am going to be out in garage. My neighbor leaves his on all winter to take the chill off of the floor above the garage. The heat exchanger is the weak link here. Its tubular steel construction. If its an everyday thing the Modine might be better for longevity but I have zero issues with mine after 3 years.

You can mount the heater directly to ceiling structure (built in brackets provide the 1" clearance required. I ended up using half slot channel from home depot mounted to ceiling, spring nuts and 3/8" threaded rod to suspend the heater from the ceiling to the height I wanted. It also made mounting and leveling easy. This worked fine but the combustion and blower fan vibrations made for noise in the room above. Later I changed it to add vibration isolators which significantly reduced the noise above. Attached picture shows some of these parts. Isolators are optional but I'm glad I went with them.

I seem to recall if you go horiizontal venting you have to use a special double wall vent pipe with a stainless steel inner liner. Also hi temp silicone to seal any seams. Instructions should say. I just used standard 3" B-Vent (double wall) and went vertical through the roof.

[tkbalt]

I have a standard 2 car garage and a Lennox gas heater - not sure of the size. I keep it set on 40 degrees and raise the temp to 50 / 55 when I am out there. It is a small unit than hangs about 1 inch below the ceiling off of rails as described by prior post. Works great, did not see a big jump in the gas bill.