floor mounted forced air heater

[duderjay]

Hey guys I had a floor mounted heater installed made by empire comfort systems. I listened to the salesman and basically got screwed

Anyways 35000 btu 270 cfm It sits on the floor and takes air in from the top thru the exchanger and shoots it down at the floor.

Doesnt work great and I am pissed, brand new garage and he put a hole through the side of the wall for the exhaust vent and the cumbustion air intake.

He came over today and said that it appears the heater doesnt seem to be adequete for the garage. I told him I got a camaro I want to restore and I like working in 20 deg c.

Now he is talking about putting in a 55000 btu unit for 200 bucks more and he will take the unit he put in back.

Does anybody have any experience with these types of heaters?

I am kicking myself in the *** for not going with a unit heater hanging from the cielling.

 

[Torque1st]

Call your local codes enforcement department.

 

[oldgoat]

It does seem pretty small but how big is the garage? If it is a double the 55K would be the smallest I'd want to go with. You say that it was mounted on the floor? I believe that most places require it to be something like a foot off the floor so that fumes won't be ignited as easy. I had a friend that put his furnace in a little building on the back of the garage and ran a duct in along the floor. Kept the floor nice and warm and didn't take the space up. With the intake at the top and he had some vents that let it also draw some outside air in he didn't have a problem with fumes being ignited.

 

[dodgeram2500]

If he's a pro he should have done a heat loss calc to ensure its the right size. Are you planning to leave the heat on all the time or just when you need it? What's the size of the building/insulation?

 

[stitch]

Figure out how much heat you need using this heat load calculator.

 

[duderjay]

r 12 insulation in the walls and r20 in the attic which is getting doubled up with left over insulation. I have vapour barrier and drywall up. It is a brand new garage and it is built tight. I actually have a problem with humidity in it right now.

Over night temp dropped from plus 6 c to -17 c and with the heater off all night I lost 5 deg c only over a 9 hour period in the garage and when I checked today at 5pm it was 5 deg c in there with the heater off also the wife drives in and out so she came in at 3 with a warm mini van. I am not worried about heat loss.

I'd like to keep the ehater off most of the time or just to maintain a temp above freezing and when I want to work in there I want to be able to turn a heater on and have it warm in 30 minutes.

The garage is 22 by 24 with 9 ft cielling.

The fella told me today he would give me my money back and take the heater or put credit towards a type of my choice. He was talking about a gas fired cielling mounted 50 to 60 k btu A renzor or a stirling heater.

I tell you tho that floor mounted heater throws all the heat at the cement slab I think that the heater is too small and also that for what I want to do like shutting it off it wont work for me

 

[duderjay]

hmmmm I am wondering if he used the right sized piping for the gas going into my garage.

he had to run 55 feet of it

 

[IanF]

I'd like to keep the heater off most of the time or just to maintain a temp above freezing and when I want to work in there I want to be able to turn a heater on and have it warm in 30 minutes.

Define "warm". In addition to heat-loss, the other very important part of the "BTU's required" equation is your Delta-T (change in Temperature). If you want it to go from below-freezing to t-shirt temps in 30 minutes, you're going to need a ****-load of BTU's.

Do you put down insulation under the slab? Is the slab insulated against the foundation? If the answer is "no" for either or both, then keep in mind you have a pretty big heat-sink that will be very difficult to get warm and keep warm.

And while it depends on the building and heater, sometimes it's no more costly to keep a space at a certain temperature than it is to make big temperature changes.

The heater specs will tell you how big the gas line needs to be. Hopefully, your contractor oversized it a bit. Line pressure can also make a difference in heater effectiveness.

 

[duderjay]

ok last night i had the sucker up to 24 c using the forced air heater and a 240 volt 30 amp 16000 btu construction heater. outside temp was -17 c.

then i shut the construction heater off and with in an hour with the furnace going full bore i lost 10 degree c in temp and called it a night.

these btu heater and heat loss calculators are ******* me off one calculater says I need a 24000 btu heater and the other says I need 55000 btu heater.

So the gentleman who sold and installed the heater said he would take it back and install what ever of my choice and give me a credit on the heater which would go towards a different one or he would give me my money back. I told him since he was being fair about it I would continue doing busness with him.

He gave me a choince between a Renzor and a Sterling 60000 btu unit gas fired heater. Also he would install it. Now I have to choose between the two. I figure 60000 btu with an eff of 81 percent would give me 48000 btu out put and last night I had 43000 btu combined output so the 60000 btu unit would serve me well.

Also a heater expert helped me out and said my line size was good