To be or not to be, that is the question

[Scheinin]

Whether is it better to turn heat off while out for the day, and bring the temperature up from 40 degrees to 66 degrees when I return, or, to leave the heat setting at 66, and let the furnace maintain the temperature through out the day? Which is better for less consumption of propane?

[SeaDog]

Myself I always turn it off have I ever measured the difference no. Probably so small of a difference in a few hours it makes no real difference.

[SailorSam20500]

I tend to split the difference. Lower the thermostat in cold weather and raise it in summer then leave the HVAC running. I figure I'm saving some both ways.

[Reverse_snowbird]

I would think, but cannot prove, that turning it off when you leave would save propane. It's going to have to continue to heat the unoccupied space.
If you're going to leave it on, consider lowering the temperature to save propane. The furnace is going to work less to bring the temp to 55 than 65.
Have you considered a temperature controlled space heater?

[NMWildcat]

This what I know from recently spending almost two months in our RV in freezing overnight temps (8 to 18 degree avg).
If you turn the heat off while out, the RV walls, floors, furniture, etc is all cold when you return. It takes any heater a long while to warm it all back up.
If you just turn it down a few degrees, it takes much less run time to warm things up to a comfortable level. Which method saves propane? No idea. We were more interested in comfort and keeping things from freezing.
You don't say if you are at hookups or not. If at hookups, keep an electric heater with a thermostat running to keep it at a reasonable temp during the day. We would set our electric heater at 72 while out, and our propane heater was kept at 62. That way at night when the electric couldn't keep up with the temp drop, the propane would come on and keep everything (including pipes in underbelly) from freezing. During the day, the electric kept the RV warm w/o using propane. In two months we went through 2 30lb tanks of propane doing this, and that was with propane only on demand water heater usage also.

[Larry-NC]

Originally Posted by Scheinin

Whether is it better to turn heat off while out for the day, and bring the temperature up from 40 degrees to 66 degrees when I return, or, to leave the heat setting at 66, and let the furnace maintain the temperature through out the day? Which is better for less consumption of propane?

To solve this equation you need to specify how long you will be gone.

Obviously, if you leave for several days it's better to lower the temperature.

If you leave for an hour, it doesn't matter much, as long as you minimize the door-open time.

My intuition is that for short times it doesn't matter much and for long times it's always better to lower the temperature. So if you need a single rule for all time periods, the rule is "always lower the temperature."

This does not take into account DW's preference. She HATES coming into a cold place and is always vocal about it.

[Scheinin]

Originally Posted by Reverse_snowbird

I would think, but cannot prove, that turning it off when you leave would save propane. It's going to have to continue to heat the unoccupied space.
If you're going to leave it on, consider lowering the temperature to save propane. The furnace is going to work less to bring the temp to 55 than 65.
Have you considered a temperature controlled space heater?

I use a space heater when I am here, but since we are staying at a site because of the CV on a monthly bases, we have to pay for electricity, last month $265.00. Propane is $80.00 for a 100 lb tank. Plus, I think space heaters are too dangerous un-attended.

thank you.

[Scheinin]

Originally Posted by Larry-NC

To solve this equation you need to specify how long you will be gone.

Obviously, if you leave for several days it's better to lower the temperature.

If you leave for an hour, it doesn't matter much, as long as you minimize the door-open time.

My intuition is that for short times it doesn't matter much and for long times it's always better to lower the temperature. So if you need a single rule for all time periods, the rule is "always lower the temperature."

This does not take into account DW's preference. She HATES coming into a cold place and is always vocal about it.

Thank you,

We live in our RV full time. We will leave for the day to do other things, usually 8-12 hours.

[bikendan]

Originally Posted by Scheinin

Plus, I think space heaters are too dangerous un-attended.

thank you.

Why would you think an oil-filled radiator space heater would dangerous?

[Scheinin]

Originally Posted by NMWildcat

This what I know from recently spending almost two months in our RV in freezing overnight temps (8 to 18 degree avg).
If you turn the heat off while out, the RV walls, floors, furniture, etc is all cold when you return. It takes any heater a long while to warm it all back up.
If you just turn it down a few degrees, it takes much less run time to warm things up to a comfortable level. Which method saves propane? No idea. We were more interested in comfort and keeping things from freezing.
You don't say if you are at hookups or not. If at hookups, keep an electric heater with a thermostat running to keep it at a reasonable temp during the day. We would set our electric heater at 72 while out, and our propane heater was kept at 62. That way at night when the electric couldn't keep up with the temp drop, the propane would come on and keep everything (including pipes in underbelly) from freezing. During the day, the electric kept the RV warm w/o using propane. In two months we went through 2 30lb tanks of propane doing this, and that was with propane only on demand water heater usage also.

Thanks, Scott, that makes sense. We are spending the winter in Maryland and are on a riverbank. Temperature this last month is mid 40's during the day and low to mid 20's in the evening. We started with our 2 30 lbs tanks, which would last 2 weeks, one week on each tank. We then got an 80 lb tank. For some reason, maybe because I was "home" more, it only lasted 16 days. I am going to follow your suggestion and not turn the temperature down to 40 when I am not home, but leave it around 60.

Thank you.

[Larry-NC]

Originally Posted by Scheinin

I use a space heater when I am here, but since we are staying at a site because of the CV on a monthly bases, we have to pay for electricity, last month $265.00. Propane is $80.00 for a 100 lb tank. Plus, I think space heaters are too dangerous un-attended.

thank you.

We have a couple of oil-filled radiators. They are really expensive to operate and it results in two warm spots in the 38-foot trailer and the rest chilly. We only use them if there's a furnace problem or to use to heat the cabin.

We believe there's no safety issue with them. It's a little tricky to manage them in a 30-amp trailer--one on the GFI circuit and one on the General circuit. If we need to do anything else, we turn the appropriate one down from 1500 watts to 900 or 600.

[Attila the Pun]

The longer it's off, the colder everything will get and the harder it will be to get the place warm again. The contents will lose heat and need to be brought back up before the thermostat will realize that you've gotten back to your "occupied" setting.
FWIW, when I had a new heat pump installed at home a couple years back, the installer said it'd be MUCH more efficient to leave it at a constant temperature than to let things cool down and then have to heat them back up. We used to set our programmable thermostat to let the temperature drop 5-6 degrees during sleeping hours.. He said that was actually inefficient - making the system work harder at wake-up time.

[Jim in Halifax]

Furnace on battery power will "die" in no time!!!!!!!!!!!!

[NMWildcat]

Originally Posted by Jim in Halifax

Furnace on battery power will "die" in no time!!!!!!!!!!!!

True, but depends on what you consider "no time". Most boondockers (including myself) have two batteries and when the heater is set to a moderate temp (60ish), the heater easily lasts through the night and until I make coffee and feel like going outside to start the generator w/o going past 50% discharged (usually).

[TitanMike]

For stick and brick houses it's recommended that the thermostats be set back 10 degrees from regular temp ehen leaving as well as at bedtime.

I use 65 degrees as my regular temp in cold weather, wear flannel shirts, and use sleeping bag on top of regular bedding.

Nothing freezes, furnace doesn't drain batteries overnight, and I'm comfortable with the 10 degree setback..

Propane seems to last a long time too.