Turning down the heat at night good or bad?

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Calypso
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Re: Turning down the heat at night good or bad?

Post by Calypso » Fri Nov 04, 2016 5:03 am

* wrote:
Calypso wrote:Insulation thickness on the inner roof makes a big difference in cold climate. Warm air wants to go up.
I put 12" of shredded blow in paper in my ceiling.
Here in Finland we use typically rock wool or cellulose wool. Cellulose wool tends to compress with time and lose some of the insulation. Shredded blow in paper is probably close to cellulose wool we use.

12" (~30cm) does not sound like much. Current requirement here is for new buildings 40cm. It's not uncommon to go to 60cm.

Good insulation works wonders keeping it warm or cool. Just need to be careful with condension stops and structure ventilations.

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Re: Turning down the heat at night good or bad?

Post by midnightbluS10 » Fri Jun 22, 2018 7:29 am

machinedave wrote:
Mon Jan 04, 2016 11:57 pm
Splitter wrote:Less temperature difference (a colder building) means less heat transfer to outside. You should be saving fuel by turning down the heat. And if your shop is colder than your neighbours, you're causing them to lose more heat to you, driving up their heating costs at the same time.

There will be greater savings in lowering the temperature difference if your building is poorly insulated or has a bunch of overhead doors, compared to a well-insulated airtight building.
Those are my thoughts as well. There are many people that disagree with me. They have a hard time with the straight 9 hours of run time of the furnace. It would be intersting to note how many times the furnace cycles in an 8 hour period just maintaining the temperature.
The solution is simple. Figure out which way keeps it on longer. 9 hours straight or 25% of every hour for x amount of hours.


Should be simple math to tell you which is costing you more.

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Re: Turning down the heat at night good or bad?

Post by jred » Sat Jun 23, 2018 2:33 am

also don't forget that if your building is tall a lot of your heat is up there you might try some ceiling fans to push the warmer air back down. although my building is 40x80 my roof height is only 10 feet makes it problems some times because its not high enough to get the 8000 pound fork lift inside..

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Re: Turning down the heat at night good or bad?

Post by stealth » Fri Jul 13, 2018 5:53 pm

Hook up a simple hour meter to furnace motor and you’ll know for sure which is better...

Also will tell you how many gallons of fuel oil used....just mult hours by nozzle size in burner...

I put one on mine...now I never have to guess how much oil is in tank....I know to the gallon... :D
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man.

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Re: Turning down the heat at night good or bad?

Post by econo racer » Sun Sep 02, 2018 4:22 pm

When coming back to work I use a kerosene torpedo heater for at least 1 hr. then use regular heat. Gets the temp back up quick for me. Must be a safe area though.

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Re: Turning down the heat at night good or bad?

Post by SupStk » Sun Sep 02, 2018 7:33 pm

My shop is a pole building with the doors facing the prevailing wind side. The insulation is TF-600 which is foil faced Styrofoam type board with double thickness on the ceiling. Heat is a natural gas radiant overhead tube heater.
I've tried it both ways, cycling the heat up and down and just leaving it at 60°. From what I could determine there was a very marginal savings, if any at all by cycling. If I'm not going to be in the shop several days the heat will get turned down.
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Re: Turning down the heat at night good or bad?

Post by wheelsup330 » Sat Sep 29, 2018 5:58 am

I have a god forsaken 60 year old Stran Steel Building that is 6000 sq ft (60x100) and 14' eve with a 1/12 pitch on a monolithic slab that has ZERO insulation around the perimeter. It was built with the best insulation available in 1962 which was (the EARTH) for the foundation, and the rest of the walls and roof are 2' wide strips of foil backed 2" low density white foam (In Alaska).

It has more gaps than the memory of a sorry democrat whore on a train to memphis and the fit and finish of the more than 2 dozen aluminum framed Zero-E single paned slider windows leaves more cold in the room than any gold digging debutant' from the klondike. The efficiency is horrible and sucks the life outta my checking account.

My American Standard Boiler (I Call it the American Bastard) burns more Natural Gas on just the pilot light than would take to fire a Trailer Hitch Mounted BBQ that could Cook a dozen burgers a side of ribs and a double brisket all damn day - running at just at an idle!! When it fires off the neighbors wonder if theres an apocalypse? My natural Gas Bill is about 1500/month!! Average, and in the winter it can hit 2200 on the high side. Our Utility comps will average your bill, and make it even all 12 mos of the year. Ive tried that and I think its a SCAM.

I found on Craigslist and (temporarly) installed a LanAir Waste Oil Burner Unit and that 140k btu unit keeps my place toasty! I PROMPTLY shut down the "Monthly Averaging" and That little SOB cut my gas bill down to about 800/month and I'm burning all the FREE drain oil I can find. About once a month I have to "tune up" the unit and that entails opening the firebox and running a Vacuum to clean out the ash buildup and change out the basic oil filters. Check the point clearance. It burns about .7 gph when its online and uses less than 1 cfm of compressed air. Pretty Slick and with a little bit of effort it is easily paying for itself. I got one of my sons up to speed pretty quick on keeping it running tip top.

I AM looking into the benefits of better insulation, and most of the profesional shop builders here are saying the BIG DEAL is to spray your BEAMS and Spray your PURLINS with 2" of Urethane. The big heat transfer comes in Alaska from the STEEL (Robbing your building interior heat) and transferring it to the metal sheeting. Any more than 2" or urethane is a waste, and if you spray the whole building inside that 2-3" on the gaps of sheeting etc is also a waste. Best cost efficiency is to use the "blowed in bags of cellulose" to fill in the gaps between the Purlins and make sure your Vapor Barrier is TIGHT!! Take that stretchy Red Vapor Barrier Tape and tape the hell outta all your ceiling gaps. Carry that 4' or at least down to the tops of your doors!! And gap your doors tight. Overhead Doors are the WORST. Set up the "brushes" to sweep the INSIDE gap, and use a soft rubber lip to fit tight on the outside that should stop most of the wind from invading the dead space.

I'm constantly working on improving my old SCAB of a shack, (beats the hell outta nothing) but I will tell you that shutting down the heat at night, NO WAY!! Caused too many Machine Probs in the Morning?? My ways on my crank grinder were WAY OFF!!

Check your stuff boys... Sweep your lathe? Cant be turning out garbage over a 15 dollar a night gas bill. Found a way to make cheap heat and im going with it.

On another note, skylights are saving on my light bill, and these new LED setups? Many can run on DC, which my roof holds big solar panels and keep my shop lit up like CRAZY for ZERO cost from Electric Utility. Coming soon, Windmill... and new Lithium Batteries... and Technology.

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Re: Turning down the heat at night good or bad?

Post by machinedave » Wed Oct 03, 2018 8:53 pm

I converted my entire shop from fluorescent to LED's. 60 watts per 8' section instead of 160 watts per 8' section. 18 fixtures total. The conversion was about $1400. I thought the bill would drop a little more. My average bill was about $235 per month. With the LED's it is now about $220 a month. I'm very happy with the new lights and glad I wont be changing those fluorescent bulbs 14' high in the ceiling. They are also totally silent.

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Re: Turning down the heat at night good or bad?

Post by 68post » Sun Oct 07, 2018 1:45 am

Hello, I have background of 35+ yrs in construction - mostly residential and some commercial. Insulation and venting, factory built fireplaces (formally certified by the Hearth Institute for gas appliances and wood burning fireplaces), sectional overhead garage doors and their electric operators.
If you are successful in sealing a building air-tight,(and you very much want to be, to a degree), you must bring in fresh air if you are combusting the interior oxygen, or setup your heater to use exterior air for it's intake.
Most never seal something 100%.
In this case an "Air to air" heat exchanger is ideal. I'm not well versed on furnaces, sorry, but I do know that a small furnace running at capacity for a long while will be more efficient than a large one that cycles on and off constantly.

High efficiency gas heat is generally the least expensive to heat within most areas, with Natural gas being less than Propane (buy propane in the summer when it's the least expensive if you must).

Do not use "brush seals" only to seal a sectional door, some air will pass thru them. Use any type of "flap seal" or 2 seals combined.
A 2" thick polyurethane foam injected garage door section averages around an R-18 (polystyrene R-10), 3" thick polyurethane - approx an R-25, if you can find an affordable 3" version (or one at all).
Use sectional doors that have an internal compression seal to make the joints air-tight, and true thermal-break btw the interior and exterior steel skins. The only good insulated door has a solid insulation core for it's entire width, interior and exterior skins (99.9 % use painted/galvanized steel), and no internal framework. A pan door ,(single sided steel with frame stiles(vertical posts where the hinges attach) also makes up ALL non-insulated sectional steel doors), with a piece of foam in the framework is an EXTREMELY poorly insulated door (R-0.5 to R-3 ) and leak air profusely , and sliding doors are very hard to seal and too heavy if insulated properly.

When you use spray foam on a building's interior it is to seal and add some R-value , but it's not enough to stop radiant heat loss, you'll need more insulation, but spray foam would be very expensive to gain the R-value needed, extremely heavy, and may delaminate over time.
Supplement with fiberglass or cellulose. Some spray on a 1/2" and go over that with fiberglass batts. It well depends on how the building is constructed on how you CAN insulate it.
Blown-in ceiling insulation cost much less than batts and covers so much better. Our attics looked like a good heavy snowfall had hit ! We used pure white fiberglass and some manufacturers warranty the R-value for years after installation of this product.

You lose most heat thru the ceiling, upper walls, and other leakage.

I'm in Indianapolis and in a seminar I attended approx 25 yrs ago they recommended an R-50 in ceilings to use an electric heat pump in our zone, and a gas or electric "backup" furnace for more heat !! Likely upgraded since then.
R-38 in ceilings should be a minimum anywhere (heating or cooling), our upgrade was to a minimum R-44 , with any more being less cost effective (but utilities never lower pricing - so...). Insulate cold air returns too - if they are not within the envelope being conditioned.

Tim King / Garage Door Service of Indiana, inc., and formerly d/b/a Indy Insulation and Fireplace.

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Re: Turning down the heat at night good or bad?

Post by Dave Koehler » Sun Oct 07, 2018 9:54 am

Wheelsup,
Good post with plenty of descriptive adjectives.
Is that 6k fully open? If so Have you considered walling it off in sections so you have treated air where you work and some cooler storage areas?

While not near your size my pole barn building was not originally built for my purposes and suffers/suffered from the same issues.
Once you get the important insulation figured out I can tell you the best thing I did was to get rid of the gas overhead heater.
Like yours it was a giant gas suck with little effect.
I replaced that with overhead radiant tube heaters.
Marvelous change in comfort, the equipment reaches the same temp and there was a significant drop of nearly 50% in gas costs.
I did try the night and day idea but it gained no savings.
It doesn't take long for the tubes to do their thing but I settled on a constant temp to keep the equipment, floor, etc at the same temp.

These days I have added a mini-split so I have AC in the heat and heat in the cold. I have it set on 70 degrees.
My net results based on thermometers located around the building is averaging 67-69.
When it gets chilly outside it sends out heat and as the day progresses it slowly changes over to AC.
Really a neat deal and makes for consistent equipment and tool measurements year round.

My shop on the north side faces a 200 acre farm field and winter winds whipping across it can be bad to OMG brutal.
The mini split can't keep up all that well in real low temps
If there is little wind contribution they seem to keep up to just below 30. Forget it if it is in the 20s.
I experimented with the radiant tubes thermostat so they come on when the temp gets below 30 around here when wind kicks up.
The end result is my spring, summer and fall power bills are consistent with the occasional low cost month.
It has to do with the way the power companies juggle their numbers but never figured out why or when it happens.
In the aforementioned winter temps my tube heater gas bill has been cut in half yet again as a result of combining the tubes with the mini split.

I am still adding more insulation to the ceiling as I go along.
I have also done the Daylight LED lights replacing some metal halide warehouse type lights.
I also have some variable speed fans that do help. Fast speed to swirl around the AC and slower to move some of the upper heated air down.

I give my used oil to a customer down the street that heats his block built garage with an oil burner.

If I ever build a new shop any doors will be on the east side where wind is at a minimum.

No room here for a preferred windmill but roof mounted solar always looks promising.
Dave Koehler - Koehler Injection
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http://www.koehlerinjection.com
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