How long does it take you to raise your house temp by 10 degrees?

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MrEd

Feeling the Heat
May 9, 2008
426
Rural New England
I am curious for those of you heating with wood, how long it takes to raise the temp of your house by 10 degrees (approximately). When heating with oil, it was never really an issue, set the thermostats and forget about it. My storage is not on-line yet (will be in December), but right now by morning the house is down around 60 degrees when I start a new fire, seems to take 2-3 hours to get it close to 70, and I am surprised it takes so long. FWIW I have all cast iron baseboards, which I assume take longer to start throwing heat then fin baseboards (but also seems to hold heat longer).

When the storage comes on line I look forward to waking up to a house that is still 65 degrees or so, and only needing to bring the house up 5 degrees, i.e. smooth out the curve a bit.

So how quickly does your house respond?
 
I have fin tubes in 2200 sq feet, and an old simplex boiler. But even pumping full 180 degree water continously, it takes 3+ hours to move the temp 10 degrees, assuming it's still cold outside (which caused the 60 degree resultant morning temp.) I don't mind flicking on the oil to get the water temp to 180, then cutting it, and let the wood keep it there.

Storage would likely raise the low temps, which I don't think I'm going to do. My next step is to further insluate the cellar walls, to get their average temp up 3-4 degrees to 68 or so, and hope that mass helps to moderate the temp dips.
 
I don't really know - I've never had to raise it that much. It's very dependent on outside conditions.

I made a serious blunder in designing my house - I basically created my own version of the Slantfin spreadsheet (anticipating them by a few years). I calculated the number of feet of baseboard needed to make up the heat loss, and rounded up to the next standard length. I ended up with 52 feet of baseboard for the whole house. Worked fine, but there's NO extra capacity to actually change the house temperature.

I've since added some extra in the basement zone, and I'm adding radiant under the main floor.
 
I'm with nofoss, as I have about 50 feet downstairs, and the same upstairs, which I hardly ever turn on (unless we have souther houseguests).

This is an '84 design, so all outside walls have BB, except doorways, kitchen cabinets, and where the new French door is that I put in this summer. So, this design was for a steady heat flow, with no nightime set back. I have to go to that when it's in the serious neg numbers. But more radiation could kick the recover rate up. But it might take a lot more BB, or maybe some nice radiant panel. Basically, it's not the boilers fault that it takes so long.

I've looked at doing a radiant floor in the Kitchen, but haven't been impressed with it enough yet. I'm not interested in dropping my water temp so that I can use "cheap" pex under some plywood/finish floor, etc. I'd be more likely to go with a panel under the breakfast bar that we sit at anyway, if it can take 180 water, run by a non-elec valve.

It seems to me that that is where we sould be headed for the next gen system. Non-elec valves, on radiant panels, all done by thermosyphon, out of massive storage, solar and wood heated, oil back up that heats house, not storage. Hmmm, sounds like another thread.... I have met a Solar installer that is headed that way, from Thetford, VT or thereabouts.

Al
 
Im sure its completely dependant on the size of your house, heat load, heat loss and boiler output but heres us.

Our house is a cape with about 1300sqft, a good cents home so well insulated. Ive got the oil boiler completely turned off (havent burned a drop of oil this month)

We were out late and when I got back (around 9:00 the house was 62 degF. We fired up the wood boiler and it was 68 deg by 10:30. About 3:30 am I got up and saw it was at 70 and cooling, I filled the wood boiler again and was at 72 at 5:30am. So in 1.5 hours we gained 6 deg.

Its nice knowing we arent burning any oil at all. Im sure by December we wont make it through the day and will need the oil boiler on to bridge that gap...


~ Phil
 
It takes me a little over an hour to raise it from 55 to 72
 
I have my thermostat set backs from 68 to 62 in a two story cape with addition for a total of 2400 square feet.
Yesterday afternoon with 135 degree water in the tank it took 55 minutes to bring up the temp 6 degrees when it was 30 outside. This morning with 170 degree water it took less than 20 minutes and it was 17 outside. There are lots of variables but so far I am thrilled with the Tarm performance
 
While away for Christmas I set my thermostat to 50*. when we got home I reset to my regular program 61* at night 65* for days. We got home at 10 pm, by 3:30 am the house was up to 58* with the circulator on most of the time. House hit 61* before 6:45 am and then it went up to day temp in the normal amount of time.
 
10 degrees in my house with the wood furance only would take 2-3 hrs.(kick on the gas fire place with the wood furance about 1hr)
 
I went down to florida for the holiday so i shut down the wood boiler and set the oil boiler to keep the house at about 60. when i got back 10 days lateri cleaned the ashes out of wood boiler top and bottom. raised the temp on the tstats fired up the wood boiler so between the 2 heat sources I got the house up to 70 in about an hour or so. took me a while to get good coals again after cleaning out the firebox so most of my warm up was due to theoil burner. dont know if that will help or not but thats my recent experience
 
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