Brrr. Time to get the shop heat working

[pritch]

We got a few inches of snow the other day, so I guess it's time to get the heaters working. I have several options. When I need instant gratification, I have one of those ceramic units that just mount to the top of a propane tank and burns. But when I anticipate working out in the shop for an extended amount of time, I have this set-up:

A propane water heater with a circulating pump, filled with glycol


Connected to these:


I thought it would work better than it does, propane just don't deliver the heat like natural gas would, but my total cost into this is zero, since I scavenged all the parts from buildings I have remodeled. A 5 gallon bottle of propane will run it for about 36 hours, and it will raise the temp inside the shop to about 60 on even the coldest days. I have a passive-solar system, too. I have about 1100 square feet of south facing black shingles, so my attic heats up quick. I have an exhaust fan mounted in my ceiling at the low side and 2 smoke dampers at the high side and the whole scene hooked up to a line voltage controller so that when the air in the attic hits 70 degrees, the fan kicks on and the dampers open and it blows all that all that warm air down into the shop. This works really well after about February when the sun gets a little higher in the sky. It usually kicks on about 10 in the morning and runs 'till about 2 in the afternoon. Same as the other, total cost to me has been zero for all the parts.





When both of these are running, it is down right comfortable out in the shop!

[ETsC10]

Impressive use of salvaged materials and the piggybacked idea of dual heating systems!

Considering how easy it is to find used gas water heaters and smaller forced-air gas appliances, I would think that even a person who had to buy the materials could be able to build your propane system at a minimal cost when compared to a commercial fixture.

Can you give us further details on the propane systems parts list and construction?

[pritch]

It's all pretty simple. Those 2 unit heaters came out of a high school kitchen I remodeled. I'm sure they were original to the 1958 original construction. They were a mess, though, with 40 years of kitchen grease all up in the coils. After I got that all cleaned off I was amazed at how good they were. My only complaint is that they were designed to have live steam heating them instead of hot glycol. So they don't work as well as they could. One thing I think would help is if I found some slower-much slower-fans. These create quite a windstorm when the slats are all open and I believe that much wind don't let the coils heat up and stay at a decent temperature..



I still have 2 minor drippers that I need to fix before I finish the pipe insulation, but I need to drain it down some to do it, and I fear that the drain valve on the bottom of the water heater will break. I am looking for a big, flat pan that will hold 50 gallons before I attempt that.

As for the pump, it's just a simple Bell & Gosset circulating pump. A plumber buddy of mine had it laying around and gave it to me. He didn't want it for anything, just leftovers that we all bring home from jobs.

[pritch]

The water heater is just Run-Of-The-Mill, pulled out of another remodel. I got 3 of them, but this one was the best. I want to find a little bit better propane regulator to see if I can get a little bit more fire under it. Something adjustable. The hose is long enough that I can put the tank outside. I also built a little table for it to sit on, since propane is heavier than air and will settle. I have a piece of heavy-gage tin plate behind it, too.


I found the really cool combo gauge-pressure and temp-that I will install when I get it drained down for that other stuff.



And of course, in any closed system you must have an expansion tank. Come to think of it, I did have to buy this. I think it was like 30 bucks.



The directions said to mount it on it's side like that, but it don't make any sense to me. I'm gonna change it so it's vertical.

That's about it. I do have a line voltage thermostat controlling the fans:



And an aqua-stat so that nothing works until the pipe is hot enough. This keeps the fans from running on forever if there is no heat:



Mostly, I just love tinkering with this kind of thing.