Letting the hot air oil firnace take over while gone....

[Hogwildz]

Opinions please....

I'm going to be vising the lil woman in the next month for 7 days, and will leave the now back up oil furnace(forced hot air), do the job while gone.
I was thinking of leaving it set at about 55. What is the consensus of the lowest safe temp to set it at without having frozen water lines or traps?

Think any more than 20 or 25 gallons of oil will be eaten up, or much less/more?
I think the nozzle is 3/4 gallon per hour, but honestly don't know what that means. I seems to remember that being the max number for usage?

 

[Warm_in_NH]

You know it all depends on the house. I take care of a few 2nd homes and we go with 50 w the water main turned off (just in case) and open all the cabinet doors under the sinks to let heat into the pipes.
If you shut the main valve off just make sure you kick the breaker for the hw heater if it's electric incase u have a slow drip it won't burn out an element.
I also set mine at 50. Just got home today. 5 hours later it's just feeling warm again.

 

[FanMan]

3/4 GPH is the instantaneous usage i.e. what it would use if it ran non stop for an hour... which presumably it won't. So it will never use more than that.

As for a safe temperature, it depends on your house, how much insulation you have, how close the pipes are to the outer walls, whether you have a crawl space or a basement, and how cold it is outside.

To be completely safe, you can either shut off the main (so nothing bad happens if a pipe does break), or leave the water dripping somewhere.

 

[Redbarn]

We go with 50 w the water main turned off (just in case) and open all the cabinet doors under the sinks to let heat into the pipes.
If you shut the main valve off just make sure you kick the breaker for the hw heater if it's electric incase u have a slow drip it won't burn out an element.

x 2

 

[velvetfoot]

I used the wifi thermostat for like the 2nd time when we came back from visiting-nice to come back to a warm house, oil or no. We go with 55-I think that's plenty warm. Believe it or not, we have it rigged so we turn off the water every time we leave the house-just flip a switch on the way out.

 

[peakbagger]

If its an older home with piping near exterior walls, the temp may need to be higher. There are timers that run the circulators every so often so that if there is a cold spot that the water doesn't freeze but that's a long term fix to a problem you may not have. The bigger issue is usually domestic water lines in exterior walls or areas that don't get heat. Most folks have probably figured which ones are the bad actors and have dealt with them. Worst case is turn the water off at the valve and leave the taps open, which normally keeps the line from splitting. I would leave any cabinet doors open in areas with piping.

 

[Hogwildz]

Velvet, how bout a link to that wifi thermo, sounds interesting.
No pipes in any outside walls. Everything runs up from the basement, and straight up to each faucet, etc.
The second floor piping runs though interior walls. and some of those are in a closet semi exposed inside the closet. The closet while not the warmest place in the house, has a louvered door and does not to seemt o get colder than any other cooler area of the house.

Thinking of either 50 to 55 degrees, shut well off, shut water heater off, and not sure about draining the lines. After all, this is why I am running the heater. If I was to drain, no sense leaving the furnace run.
House was a cabin, with the roof and a couple walls ripped out and raised to a full cathedral ceiling second story and prolly over quadrupled in size around 1996. House is fairly well insulated, some air leaks to the addition, until I finish the addition. Basement on coldest days maybe 48ish to 55ish.

I will leave the cabinet doors open, and see what happens when I turn the water back on when I get home.
Actually, think I will have my father turn everything on the morning I fly home.
I feel dumb asking about all this, but it is one thing I have never dealt with. I usually never leave for more than 12 hours or so in the winter. So have no experience leaving the house alone in winter for an extended period of time. Before I moved in and was coming up on weekends, I did shut off the water heater & well pump when I left each time, but that was in the summer and more of a precaution to any water issues while I was gone.

I almost expect a nice downdraft in the liner when I fire the beast back up. Deal with that almost every year at first start up. I am a wood burner, I like the smell to a degree. Adds to the rustic atmosphere.

Edit: No copper lines, all PVC with Pex used at addition(which is off and drained already) and Pex used for any repairs.

I know tough to tell, but any guesses at how much oil will be spent during 7 days at 50-55 degrees with fairly insulated house, but not the tightest like todays houses?

 

[velvetfoot]

http://www.ecobee.com/solutions/home/smart-si/

 

[woodgeek]

25 gallons of oil is about 2.5 MBTU delivered. This is about the same as 1/15th of a cord of hardwood, 1/5th of a facecord. Would that be enough wood to keep your house at 50°F for a week? Probably depends on the weather...we get a cold week, prob not. A warm week, no problem.

I think 45-50°F would be plenty (in our mild climate) to avoid pipe freezing.

You could get a a space heater with a thermostat, and set it lower than the oil stat as backup. Unless you got a very cold week, I'd think 1500W would be enough to keep a house above freezing in these parts....the average daily temp in January is 30°F.

 

[Hogwildz]

Don't forget we are about 10 degrees colder than you pretty much after you go through the tunnel.
I don't go through a cord a month of wood. 1/5th face cord sounds close. And burning wise, that keeps me at 68-70 during the day 66-68 at night sometimes a little lower on the coldest of nights/mornings. Sometimes a little higher on warmer days/nights.
Get some decent passive solar on sunny days, but pretty much loose that back at night.
I have to check, but am pretty sure I have at least a 1/4 tank. I think the tank is 200g, so I should be ok.
I'll have my father come check on the place a couple times during the week.

 

[hearthofgold]

Opinions please....

I'm going to be vising the lil woman in the next month for 7 days, and will leave the now back up oil furnace(forced hot air), do the job while gone.
I was thinking of leaving it set at about 55. What is the consensus of the lowest safe temp to set it at without having frozen water lines or traps?

Think any more than 20 or 25 gallons of oil will be eaten up, or much less/more?
I think the nozzle is 3/4 gallon per hour, but honestly don't know what that means. I seems to remember that being the max number for usage?

Since you have hot air, the registers have to be sealed for the wood stove to be efficient, and usually the return ducts don't have a way to close them so they need to be blocked up any way you can. Makes a very big difference. If you don't know about this, you'll be very surprised, like I was, and damm it to hell it took me 30 something years to realize it. You'll burn less wood and the temp will be more stable, very noticeable difference.

 

[semipro]

I think 45-50°F would be plenty (in our mild climate) to avoid pipe freezing. You could get a a space heater with a thermostat, and set it lower than the oil stat as backup. Unless you got a very cold week, I'd think 1500W would be enough to keep a house above freezing in these parts....the average daily temp in January is 30°F.

Plus one on both counts (temp and electric heater). I think you could even go lower since your pipes are not in the outer walls.