Second thoughts on heatstar hsu 45

[a1machinist]

Recieved my heatstar 45000 btu forced air heater this week and am worried it will not be big enough and maybe I should have went to the 75k. Garage is 28x40 with 8' cielings, r13 in the cielings with drywall and r 8 in the walls with osb. Please tell me this furnace will be adaquate.

[curiousB]

I have a 3 car garage and it is plenty of BTU's for IL. Depends where you live. You look a little bigger but my 45k isn't running much once set temp is reached.

If you are up in Alaska maybe upgrade otherwise go with it. If its undersized you can always sell on craigslist. These are hot sellers. Pun intended.

[jvitez]

1. Where are you located?
2. Are you heating the shop continuously or intermittently?
3. Why so light on insulation?: Old garage?
4. Work/play shop, or working garage? Lots of door openings, or mostly kept closed?

[a1machinist]

1. Central Wisconsin.
2. Want to heat it continuously but may decide not to after my first gas bill if its through the roof.
3. Its what I can afford at this moment currently have about 2k in materials waiting to go up. Its a older pole building.
4. Working garage, one service door and one 12x8 garage door no windows.

[ishiboo]

You cannot heat that continuously with that insulation, your gas bill WILL be through the roof. A 45k may have been oaky if it was well-insulated and you didn't plan on having it hot.

Just FYI, R-60 is recommended in ceilings in Wisconsin. R-49 is the minimum recommendation. The 45k in winter here will run nearly continuously and suck a ton of gas.

I would buy a kero heater and run it when needed until you can afford to do things right. Lowes is blowing out their winter heaters, the 220kbtu is on sale for like $199 or so down from $400.

[a1machinist]

Figured I can always add insulation down the road as funds permit. But wanted to get started now. If I go with R-60 would the 45k be running constantly?

[brewchief]

I did a rough heat load and came out with about 36,000 btu's. Thats with r-11 in the walls since it was easier then setting up a new value in the program.

45k x .80(since that heater will be 80% efficient) is 36k, it looks to me like it will be on the edge. FWIW that's with indoor temp at 65.

[boo coo tracks]

First thing I would do is try to find out how much heat is going up that vent pipe! Then look for air leaks & insulate.
My 2 cents!
Tracks

[jvitez]

I doubt 45K will be enough in the midst of a Wisconsin winter for almost 1200 sq ft with such little insulation. One option is to install it and see what happens, but expect to use a lot of NG. You may need to supplement with a portable kero or propane heater, until you get more insulation up.

[a1machinist]

Well I will be talking with heatstar at some point today as the unit had shipping damage and they want me to ship it back and they can send a new one out I will talk to them about upgrading to the 75k. Just seems like the 45k is going to be too close to borderline.

[Parrish416]

I have a 3 car garage and it is plenty of BTU's for IL.

[curiousB]

Originally Posted by Parrish416

I have a 3 car garage and it is plenty of BTU's for IL.

Insulation standards for the living space and those for a garage are quite different. The living space is conditioned 24x7x365. The garage may not be. Further while it is advisable to put a good amount of insulation when doing the construction adding it after the fact, however, can be expensive and of little effect. The link below shows the rapidly diminishing value of adding R value. R13 gets you 93% impact, the extra R47 to get to R60 would at best get you another 5%. This is not a linear relationship despite what all the insulation company's marketing literature suggests.


So if this is a heat it up for a Saturday of wrenching in the garage I wouldn't do anything about the r13 ceilings unless it is dead easy and cost is no object. I suspect weather sealing garage doors will have better impact than adding R value to the ceiling anyway. If it is blank sheet, new construction then put in as much as you can afford. Its cheap at build time. Just pay as much attention on weather sealing (air gaps, air flows, vapor barrier integrity) as you do with dumping glass wool everywhere.


http://www.buildings.com/ArticleDeta...cleID=6061#top

[Mmfh]

Nice thing about going with the bigger unit is the fact that you will be able to bring up the heat a lot faster. It will take a hour to get it comfortable instead of two or three.

Just sayin