I agree. The initial BTU calcs for my detached 2car garage indicated I would need something around 17500BTU, since I wanted to go electric that would have been a little over 5000W.
I had been checking Craigslist for a while and saw this Dimplex heater (DGWH4031) come up for $80 - brand new. Decided that since I was in the process of finishing the garage I would just put some extra money into the insulation on the walls (R19) and ceiling (R38) and that I could make the Dimplex 4000W unit efficient enough for my space. On days where the outside temp is down here 10-15degF, I'll plug in a secondary small 1500W space heater if I need to supplement the Dimplex. I also spent a lot of time airsealing the garage, including caulking the sill and top plates interior perimeters. All of that little detail stuff pays off.
But overall, I'm satisfied with the Dimplex. I was able to do the entire install including the $80 for the heater for a little over $100. Found 12' of 10-2 wire at the Habitat ReStore for $1.50 for the coil. You'll pay that much per foot at Lowes for a roll of 25'! Breaker was $15, outlet another $5. Done deal!
If I went gas, I would have spent $100 alone on just the iron pipe for the trench run to the garage. Operating cost is less expensive here in Syracuse NY for electric heat - if I run it for 2-3 hours a day, I'm looking at about a $12 increase in my monthly electric bill.
Prior to completing the insulation for the garage, the Dimplex could raise the garage temp 11degF in one hour. I haven't measured the temp rise per hour now that the insulation is complete and the drywall is up (need to rehang the heater on the wall again)... but just by feel there is a noticible improvement in how warm the space gets in an hour.
