Research Overload

[Ramper]

I have been researching how to heat my 30 x 40 detached shop in MN for what seems like FOREVER. I have insulated the walls 3" of EPS foam, then an air gap then Prodex then the walls will have steel barn roofing installed. The ceiling has 6 incheds of EPS foam, air space, Prodex and also the roofing material. I have 2 insulated overhead doors and 2 man doors (with storm doors) and two small windows. The have gone back and forth with heating ideas.

I have propane or electric as options. I have a 7.5 KW Dayton unit that I have not installed yet. I THINK I want as infrared overhead tube heat, but I really am lost. The heat loss calculators have me at about 60,000 BTUs, but I think that is low.

PLEASE HELP

 

[Jackfre]

Trust the numbers. I just looked at the bin numbers for Minneapolis and it shows that you will have about 175 hrs/year below 0*, 800 from 0-20, and around another 3500 from 20 up. It's freakin' cold there man! The heat loss number in your well insulated structure says 60k. If you oversize it you end up with short cycling equipment that starts and stops all the time and is not as efficient. What is it that wears out equipment? Starts and stops! IF, your heater is a bit undersized you may find that on those coldest days that you may drop into the 50's with it perking right along. Put a sweat shirt on. With your radiant tube heater over your primary work area you will be in good shape.

Most heating equipment is grossly oversized by design and then oversized by selection. You are below zero 3.8% of the heating year and your heating equipment is selected to satisfy that condition, meaning 96.2% of the time it is in various stages of gross oversizing. Then we are oversized by selection. As you said, "I think it should be bigger". Everyone knows that is for her to say

 

[bullnerd]

I'm in the same boat! Same size shop too.

Thinking too much!

I have a plan and am sticking to it!

Except for the unit or IR heater part! Damn it!

 

[Ramper]

As you said, "I think it should be bigger". Everyone knows that is for her to say[/QUOTE]

I have NEVER heard that from anybody!!! That is my story and I am sticking to it.

 

[NXGTS]

Same here. I bought a 75,000 BTU propane heater last year that is still sitting in the box taking up space. I've been doing some reading on here and it looks like heating with electric might be a little more efficient than propane. Now I'm thinking of doing 2 5000watt heaters or possibly a 10000watt model and only installing one. Too many decisions.