Ok so I have a garage that is 14x28x11 I have bought a space ray cold blocker 50k radiant tube heater works great on objects an cars since I paint dust free. I realized it takes to long to heat garage so I bought another heater a hot dawg 45k mounted it on ceiling its about 11ft high takes awhile to heat since its high an heat rises. So I have a idea to mount a 45 or 90 degree air duct elbow would that work to flow the heat down to floor or would a 12x8 duct in front of heater about 10ft long with 4 vents? At work I detail an we detail in a small two bay garage an to heat it with a house furnace with a 12x6 vent with 3 vents an it heats it nice an hot garage is say 20x25x9 with a hall an another? HEAT THROW I though it was how far the fan would throw heat? The hot dawg said 26ft but I don't feel it from far side of garage so what's the deal? Thanks
Hot dawg 45k need more heat flow
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DPelletier
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Beat me to it; Only blower type unit heaters should have duct installed - propellor types aren't meant to have ductwork and can't deal with the increased static pressure. Ceiling fans are our typical recommendation for this situation.
Dave
nehog
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Same here, I have a ceiling fan to move the air. Also if your unit has deflectors, aim them down too...
I keep my ceiling fan on 24/7 in the winter, low speed.
I keep my ceiling fan on 24/7 in the winter, low speed.
I've got the same size Hot Dawg in a 24X22X8 garage and it works great. Walls and ceiling are insulated. Your cubic footage is about the same, so it should work out. Try the ceiling fans and seal up as many air leaks as you can. I can go from 50 to 70 in under 10 minutes.
I was thinking of installing two fans on each side of garage aim them up so they blew the air back down. Also the vents on heater **** there's only 3 what about I put a 45degree elbow so it forces the heat down more? Reason why yours heat nice is cause u have 8ft ceiling mines 11ft
darkk
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I have a Hot Dawg 45,000 btu propane furnace mounted at about 9 1/2 ft high in a 22x24 garage with open ceiling (vaulted) to about 13 feet. My garage stays comfy even in really cold weather. My garage is also insulated pretty well except the 7x8 door. I keep it at 45 deg most times, I turn it to 55deg when I need to be out there. It takes a little time but will warms up relatively easy. Your heater is mounted way high, I thought mine was but it's doing ok.
About the radiant heater I only use that if I'm working on car or painting as it heats everything up. An I turn both heaters off since I'm using propane cause this is side work the hot dawg makes it comfy but I can't feel it blowing!! Funny thing is about the rods I was just thinking about lowering it 2ft lol also gota ? About the fan I noticed in a few shops there heater throws the heat pretty far an this hot dawg can't really feel it far away
Relax
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Would the same problem exist if it were ducted from the fan side? Would this pull the cooler air from below, drawing the warmer air down to replace it?
Fun pain
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Sounds to me you need some insulation, badly... 14*28=392 sq ft.... and you are useing almost 100kbtu? OUCH
by my calculations if you have NO insulation, no windows and no doors (just a solid enclosed box)
you would need about 70kbtu to maintain a 40 degree difference from outside to inside.... doors, windows will raise this number of course...
buy just adding a 1" of rigid foam to the entire interior, would drop that need down to less then 15kbtu to maintain a 40 degree difference from outside to inside. This is not adding in windows or doors and assumes that the building is air tight... so this won't be exact, just a comparison of no insulation to R-5 continous insulation for your given sized enclosure.
by my calculations if you have NO insulation, no windows and no doors (just a solid enclosed box)
you would need about 70kbtu to maintain a 40 degree difference from outside to inside.... doors, windows will raise this number of course...
buy just adding a 1" of rigid foam to the entire interior, would drop that need down to less then 15kbtu to maintain a 40 degree difference from outside to inside. This is not adding in windows or doors and assumes that the building is air tight... so this won't be exact, just a comparison of no insulation to R-5 continous insulation for your given sized enclosure.
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DPelletier
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ForceFed70
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Instead of ducting, consider installing a ceiling fan. I think you'd be much happier with the result.
DPelletier
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Yep, ducting is a bad idea, lowering is a bad idea; just use a ceiling fan if stratification is an issue.
I thought I might need one with my 12.5' ceilings but my electric unit heater distributes the heat relatively well. It's a little warmer at the ceiling than at the floor, but it isn't a big problem.
Dave
I thought I might need one with my 12.5' ceilings but my electric unit heater distributes the heat relatively well. It's a little warmer at the ceiling than at the floor, but it isn't a big problem.
Dave
I don't understand why lowering the unit would a problem, unless the OP has clearance issues. The Hot Dawg is nothing more than a unit heater and they are hung by threaded rod all the time. The install manual for this unit clearly states that it can be installed that way. I will agree that installing a ceiling fan or two will most likely solve his problem, but lowering the unit would probably be cheaper in the long run.
DPelletier
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It's just not good trade craft. Long hangers aren't as stable (we actually need to install seismic restraint wires too), unit can move around more, looks crappy, venting needs to be extended, gas, wiring, it's more likely to get hit with something, etc. etc.
My cost on a decent ceiling fan is something like $56.00 so I fail to see why someone would live with all of the above just to avoid installing one? I say hang the heater at the proper height (as high as possible while maintaining the clearances stated in the Installation instructions) and install a ceiling fan IF it's needed.
Dave