Garage heater upgrade - efficiency questions

[djb25]

Hi everyone,

I just posted a separate thread looking for some info on replacing the power vent blower on my Modine hanging garage heater.

This has lead me to think about just replacing the heater with a more modern version. I'm not sure how old my heater is (I acquired it second-hand, for free).

Anyway, what I have now is a Modine PV-50, 50,000 BTU natural gas hanging heater. It's rated 80% efficient, and is power-vented. Air circulation is via a large propeller fan.

My garage is 20x28. It has R-19 fiberglass in the walls. The ceiling isn't quite finished yet, but it is a cathedral ceiling with 2" r-13 foamboard. It will eventually have blown-in insulation as well. It will end up being at least R-30.

The newer heaters I've looked at appear to be rated at around 83% efficiency. I'm guessing that a 3% increase in efficiency isn't worth the cost of a new heater. The only thing that seems like it could be useful is the squirrel cage blowers in the newer models. They seem like they would move more air around the garage. No idea if that would actually make any difference, though.

Anyway, it looks like there is no reason for me to buy a newer heater, but I'd like to get some advice from the forum before I make a final decision.

Any thoughts?

 

[Showkey]

If I was going to upgrade .........I would hang one of these from the ceiling horizontal:

http://www.alpinehomeair.com/viewcategory.cfm?categoryID=128

40-60k would be more than enough, get you 96% eff and easy vent with PVC.

 

[1953mercury]

If I was going to upgrade .........I would hang one of these from the ceiling horizontal:

http://www.alpinehomeair.com/viewcategory.cfm?categoryID=128

40-60k would be more than enough, get you 96% eff and easy vent with PVC.

You would have to keep the space heated all the time if you use a condensing unit like that. Mike

 

[finn]

Fix what you have: A 3% improvement in efficiency well never amortize the cost of a new heater. Put the money in better insulation, instead.

As noted, condensing furnaces need freeze protection, so you are condemned to heating the building full time if you go that route. That will eat up any savings from the efficiency improvement too.

 

[djb25]

I have to agree. I can't see a 3% increase in efficiency being worth much of anything.

Is 83% pretty much the top end for a garage heater?

 

[Showkey]

You would have to keep the space heated all the time if you use a condensing unit like that. Mike

Yes ........garage above freezing would be needed and a good thing. I found letting the slab go below freezing is bad thing for heating recovery and condensation issues over the long run.

 

[CNGsaves]

OP . . . . . Update GJ Profile with your LOCATION.

Hard to get best advice when GJer's are guessing at your environment/weather.

Even in harsh climate, that 50K Btu heater will be more than fine for your 2 car garage.

+1 to use what you've got.

 

[djb25]

OP . . . . . Update GJ Profile with your LOCATION.

Hard to get best advice when GJer's are guessing at your environment/weather.

Even in harsh climate, that 50K Btu heater will be more than fine for your 2 car garage.

+1 to use what you've got.

Oops. I thought my location was in my details. I'm in north central PA.