Heating the garage

   / Heating the garage #31  
Alan, I sent an email to the folks at "Home Energy" (Not to be confused with "Home Power" magazine with a virtual communist editor) essentially to try to get us some professional assistance. Their staff has folks from many respected organizations in the energy conservation arena, places like UC Berkely, Oak Ridge National Lab, Lawrence Berkely (Bezerkely?) National Lab, and so forth. Basicaly, I asked how to heat an intermittently occupied space with a goal of having a "shirt sleeve" environment and a mandatory requirement of working glove free. I gave additional requirements of quick response since advance scheduling was not possible, combustion air not to be taken from heated space for dust safety, and products of combustion to be vented outside the heated space for health and condensation/rusting considerations. Sure hope they get back to us. They may choose to reply in the "Letters" section of the magizine in which case we could get a reply in the Nov-Dec issue (about mid November). They may, of course, not reply at all.

Although intended more for the professional working in energy conservation applications of HVAC, this magazine is written at a level that most homeowners with a technical interest would appreciate. No harder to track than say Pop Mech or Pop Sci.but written a little more soberly (but not withought a little humor once in a while). NOt exactly a "Consumers Reports" of the HVAC world, they nevertheless require all advertisers to provide substantial proof of any energy claims made for products. No snake oil here!

Do not read anything negative between the lines here regarding any of the annecdotal reports of "I did such and such and it worked for me" All responses were interesting but I, for one, would like to get some engineering insight into what the experts think works well. Our collective experiences brobably do not come close to theirs in this area. Not to say that anyone is wrong for doing/liking their current system. If I had a much better income stream I would go in-floor hydronic with some additional radiant measures throughout all my spaces, including outside slabs, driveway aprons, and sidewalks and never shovel snow but it isn't realistic for me. I need to consider total installed cost of ownership/operation as well as performance.

In closing, this latest word from California. It seems that it is now essentially illegal in California for heating/cooling contractors to use duct tape on, dare I say it, DUCTS! The attachment is Alan Meier the executive editor of "Home Energy" with a roll in each hand and in case the writing on his cap isn't clear enough, it says, "Duck Tape Pro".

Patrick
 

Attachments

  • 8-191774-ducttapedelme.bmp
    111.6 KB · Views: 136
   / Heating the garage #32  
Has anyone considered passive solar heat as a supplemental heat source? That, coupled with low energy ceiling fans to distribute heated air, should cut down heating costs by a fair bit.
 
   / Heating the garage #33  
Ozarker, Yup, Ah deeid! Not everyone has a good southern exposure or enough clear days to take advantage of it. I think I do. I have been considering an active system, well sort of... Definition gets foggy when you use a thermosyphon to circulate solar heated water with no mechanical pumping. Solar water heating pannels located lower in elevation than the storage tank or the in-floor hydronic tubing will circulate heated water through the tank or floor anytime the water heating pannel makes water hotter than the coldest water in the tank or small header(footer?) tank for the floor. For any uninitiated folks listening in...
What happens is:

1. The sun shines on the solar pannels and heats the water in them.
2. This water expands when heated and is then lighter than the cold water in the floor or tank.
3. This warmed water rises to the tank/floor while the coldest water (in the bottom of the tank) flows downhill by gravity to the solar pannel.

As long as the sun shines enough to heat the solar pannel hotter than the coldest water in the slab or tank the thermosyphon action continues. When this condition is no longer met a check valve prevents reverse flow and having the tank or slab cooled by the solar pannel being used as a heat sink to cool the fluid. Some folks choose to use a small efficient pump to increase the flow if their layout isn't conducive to sufficient thermosyphon effect. You can use a tank of water to store heat during the day when production may outrun demand and then circulate that water through the floor when you lose the sun.

There are other possibilities for a system like this and one of the ones some folks like is based on the fact that the "system" doesn't care how the water is heated so supplemental heat can come from a wood scrap fired boiler or from burning your old oil or subscribing to all the junk mail you can and burning it or or own little atomic pile or whatever. This heat can be generated when it is convenient to do so, stored as hot water in THE TANK and then used later when you need it but may not want to play with fire. Most ways I've seen folks burn their woodworking scraps etc results in a lot of heat for a little while. Storing it in water levels out production and demand.

In-floor hydronic isn't the only way to take advantage of most of the above... Get creative, plumb some old car radiators up to the hot water and blow a fan through them.

Patrick
 
   / Heating the garage
  • Thread Starter
#34  
Now you went and did Ozarker!!!/w3tcompact/icons/smile.gif Opened a whole nother can of worms. Not much into solor heating but living on top of a hill wind power has crossed my mind. People here in Vermont have had a hard time getting in windmills because of neighbors and noise generation. I do like the idea of solor power for the house because we are right out in the open. The garage is going to be right in the middle of Maple and Apple trees.
My wife is now rolling her eyes because of the last to posts from yourself and PatrickG. She says she thought this was a tractor forum not a heating forum./w3tcompact/icons/smile.gif If she only knew what was discussed on here!!! She'd have me disconnected because most of the projects I come up with cost some of that green stuff.
Thanks again.
 
   / Heating the garage #35  
Just tell her we have to provide a warm environment for our tractors.
 
   / Heating the garage #36  
Sounds like a great system you have planned.

I have southern exposure in my house and have plenty of glass for direct gain in the winter. It works well. I am considering a sun room addition when I redesign and replace my back deck. I think it would pay for itself in energy savings over about 10 years.

When I finally get around to building a shop, I plan to add a system similar to what you describe as well. That with a few windows to heat the floor and ceiling fans to circulate the air should keep the shop comfortable with little additional help.

I also plan to have a couple of dehumidifier out there as well. Metal buildings seem to produce a lot of condensation and condensation = good water for gardens. The dehumidifier in my basement gives me about 5 gal a week. I use that with the rain water I collect from the roof to water gardens.
 
   / Heating the garage #37  
Ozarker, I'm sorry, I don't mean to imply I will build everything I describe. My shop is so voluminous that heating all the air is not cost effective. I have 14x14 rollups at both ends which can exchange the air pretty fast if there is a breeze and that is as close to AC as it has ever had. I was never in the shop when the prev owner ran the overhead hanging gas fired forced air unit as the tank was gone when I first saw the place. He left behind a home brew stove made from thick wall pressure vessel (about 35 gal or so) It has a valve on top to control the drip of fuel oil and he had a pannel with a flue pipe though it he put in the window when he used the stove. I assume, since the shop was used for dozer maint (and insight into his nature from many other clues) that he burned waste oil in the stove. Could have burned diesel but that would be out of character.

I considered that I might separate off a space and put in a drop ceiling with storage overhead (way smaller space than whole shop as the shop is about 35x70 with about 25 at peak and a min eave height of about 16 ft or thereabouts) so I could have AC in a limited area and a place that would heat easily for bench work but as I may build yet another shop bld closer to the new house (This one will be over a quarter mile as the crow flies and in winter, over a half mile) I'm gonna wait and see what develops before starting on that.

Still puzzling over the mechanicals and HVAC for new place. If I go zoned hydronic off a ground source heat pump, I might plumb chilled water to fan-coil units in the new shop rather than putting in a separate pad mounted heatpump.
We are converging on a design for the new house. Down to way less than a dozen candidates now. Two strong contenders and 2-3 maybe sortas. Will be getting prelim estimates for the two front runners asap. If at least one is in our range then whoopee. I will build a shop fairly nearby and I hope to have it close enough to the house to make running chilled or heated water practical (if we go hydronic). Both front running plans are for 1 1/2 story homes with walkout basement that look like a three story from south side and two story from north side but the top floor is about 1/2 or less of the size of the main floor. I will site it with long dimension E-W for passive solar gain and hope to be able to use the southern portion of the wraparound porch as a sun room/screened porch depending on season. Have to check with the mfg of a neat door I saw to see if they will do custom pannels. It was a "storm" door, mostly glass area but with the top part operable by sliding it down. When the top glass slides down it pulls down an internal concealed screen. Looked neat. No screen in the view unless you open the window and then the screen MAGICALLY appears to just fill the opening. Anyway, by whatever means, I want to be able to have part of the wraparound porch as screen room or sun room depending on season.

Given the intermittent need for heat in the new shop and the unschedulability of its use patterns, I'm afraid in-floor, as desireable as it is, will not be practical. So, I will go with fan-coils. Not too bad of a tradeoff, considering I can heat and cool/dehumidify with the fan coil units and the infloor is NOT suitable for cooling. If you chill the floor in summer it would condense water lilke crazy so in-floor heat drives you to yet another mechanical system for cooling. the best trade I could find was the fan-coil approach with hot or cold water from the ground sourced heatpump.

I will be looking into the efficiency of "Heat Pipes" when used in conjuntion with a water based fan coil unit. Heat pipes boost dehumidification efficiencies real well with conventional evaporator coils in heat pumps or mech AC but I haven't seen anything on their use with a chilled water system. I think they may work but I need engineering data to base a buy decision not just my gut. If in the future it turns out that I have considerable wood scrap to burn, I can use it to heat the water coming into the shop, upstream of the fan-coils. I will just need to have exposed connections where a wood fired boiler could be plumbed in, in series. Same thing with propane or whatever. Could plumb in a propane fired water heater as a booster if the house demand took all the capacity of the heat pump and there wasn't enough excess capacity left over to heat the shop at the rate of rise I wanted. Once the shop was up to temp the propane booster would shut down and the heat pump would carry the steady state load (most of the time probably if I do the engineering right). Just set the propane water heater's thermostat to come on when the circulated water from the house was not up to spec. Need to wire in a relay with logic set to prevent the propane water tank from firing when the shop's zone isn't calling for heat. No sense in wasting fuel 24-7 to keep a tank of hot water on standby.

It remains to be seen if I try to incorporate solar water heating. My favored solar pannel for heating water is being mass produced now in China but my contact with them didn't do me any good as they were looking for a stateside rep and I just want to buy enough for personal use. Anyway it is a great water heater. It is like a Thermos bottle. The solar collector surface is in a glass vacuum bottle. The glass passes short wavelengths of light and IR and they are absorbed, heating the collector through which the water flows. The glass does not pass long wave IR very well so it doesn't loose much heat by radiation. The absorber has high absorbtion of visible and short IR but is a poor emitter of long wave IR so it doesn't give up much energy as radiation. Since the absorber/heat exchanger is in a vacuum, it can't give up heat by convection, leaving only conduction as a means of loosing heat. The design uses that conduction to take the heat out of the collector and put it into the water. It has a memory metal thermostatic valve that shuts it down if it starts to overheat the water to a dangerous level. (Like I would have that problem!!!) Who knows, maybe they'll work out their stateside distribution and I can retrofit a bunch of them later. Just have to leave places where they can be plumbed into the HVAC water at the shop. Really couldn't use them in summer as I will get FREE hot water all during the cooling season by recovering rejected heat from the air conditioning.

So many ideas, so little time (so little extra budget!)

Patrick
 
   / Heating the garage #38  
Ozarker,I meant to comment on this earlier but got sidetracked. Sometimes ceiling fans are not the best idea. One example would be with overhead lighting above the fan which can be annoying as the blads make the light flicker which for some folks induces seizures. In pilot training you are taught to never look at the setting sun through your prop, for the seizure reason. (Remember the lady researcher in "The Andromeda Strain"?)

You can however get a benefit of a ceiling fan (avoid pooling the hot air at the ceiling where it is useless to you) by other means. In new construction you put register(s) high in the room where hot air would accumulate and additional registers in or near the floor. use a small low power quiet fan to gently draw the hot air into the high registers and blow it out of the low registers. Retrofits used to be sold. They were like a big soda straw with a small fan inside. One end of the tube is near the ceiling and the other near or on the floor (with side vents at the botom of the tube). The fan sucks air near the ceiling and blows it out near the floor. Takes only a few watts to recover/recycle the otherwise wasted heat.

One consulting job (unpaid) I did for the US Forrest Service was for a ranger station high in the mountains with only solar electricity and not much of that. They had a new office/visitor center building, fairly well insulated rustic looking interior with high ceilings. They heated with wood and had the usual problems. Stove area was hot, good radiation. All the heated air pooled near the high ceilings and anywhere in the main room not near the stove could be quite frigid. My simple solution: Since they had at least some wind most of the time (they had a recording weather station and records over several years so no quess work.) Virtually never any long periods of cold and calm, at least during the day when the place was manned. Simple ceiling fan over the centrally located wood stove to blow in the downward direction. What was different was that the ceiling fan was powered by the outside wind, not electricity. Their stuff was 12 volt and they didn't have an inverter or enough capacity to power a decent one. Small shaft directly out the ceiling straight up through the roof to direct drive the cheap 52 inch 5 blade (K-Mart) ceiling fan (with mods). An inverted cone to keep rain out of the stuffing tube. A nice cheap sealed bearing to take the down thrust, a second bearing at the ceiling inside, and a small turbine of galvanized sheet metal above the roof. Gave instructions for their handy man to do the job and how to trim the area of the turbine to reduce the fan speed if it proved to be too wild. I cautioned them that ballance was very important on the 52 inch blades inside and they promised to follow instructions till it was smooth. Last I knew it was working fine and a concern that they expressed did not develop. The young guy, newly promoted, who was in charge was afraid he would get into trouble for messing with the Government building without authorization. Soon after they got it in and running the district supervisor toured some congresswoman or some such through the facility and no one even noticed. Seems that ceiling fans are so ever present it never ocurred to anyone that it was "out of place". Now had it been blowing the visitors coifure all around then the district super would have been looking for the off switch and trouble might have been a brewing.

Patrick
 
   / Heating the garage #39  
I have a 25x25, 9 ' ceiling. Called aropund all the heating contractros, found a used house forced air (was practically new) oil burner for $450, plus a used 275 gal. tank for $25 and it warms up in 5 minutes. I think it's 100 btu?? awesome way to go, cause it seems i'm only in the barn for 1-2 hour stints. the tank now feeds the tractor too.
 
   / Heating the garage #40  
What I did on my 28 x 34 foot garage was insulate it to the max. I also used commercial drywall. I think it is 5/8 or ¾ thick and comes in 12 foot sheets. I have 2 x 6 wall studs and a poured cement floor.
As a result of maximum insulation I use a single 2400-watt Cadet and maybe a small 1200 watt for initial heat up.
Works great but the secret is you pay for insulation once-electric or gas bill goes on forever
 

Tractor & Equipment Auctions

2001 KINCAID PRO-SERIES 1200V2 HYDRO SEEDER (A51406)
2001 KINCAID...
JOHN DEERE 2150 TRACTOR (A51406)
JOHN DEERE 2150...
Leeboy 8500 Paver (A47477)
Leeboy 8500 Paver...
2025 IR UNUSED Cleanout Bucket (A53117)
2025 IR UNUSED...
2003 GROVE TMS500E MOBILE TRUCK CRANE (A51406)
2003 GROVE TMS500E...
2018 KENWORTH T880 DAYCAB (A53843)
2018 KENWORTH T880...
 
Top