I have a 2-story colonial in CT. The heating system for the house is oil-fired (forced hot air). A couple of years ago, I finished the basement and made it a den. Since there was no heat in the basement, I installed a propane heater made for rooms - the one I installed (a Rinnai) is actually rated to heat 1500 sq feet and the basement room is about 800 sq ft. Anyway, during the winter, no one is home during the day (work and school) and I don't want the oil furnace running to keep the house warm, given the price of heating oil. (We also have a woodstove as supplemental heat but it is difficult to keep it running 24/7 when no one is home during the day). I was thinking since propane is cheaper then oil - and the propane heater has a thermostat - that I could set the basement heater to 70-75 degrees during the day and - by installing floor registers on the first floor - have the heat from the basement also move upstairs to keep at least the first floor at a moderate temperature (say 65 degrees). Since the basement is a much smaller area to heat then the first floor, the propane heater can get that space warmed to 70 degrees from 55 in about 20 minutes and then it has an "Economy" setting to only come on as necessary to roughly maintain that temperature. I would love to be able to turn off the oil-furnace during the day if at all possible. Not sure what someone would charge to install the floor registers ? Anyway, does this sound like a reasonable plan ? Would I need a supplemental fan in each register to draw the heat up to the first floor ? Any advice appreciated !

You can install gravity type floor registers. They are large and have no way to close them off. Naturally the floor joist will have to be cut and headers installed.

You can do this but there is no guarantee that it will work well. Hot air rises so that is one benefit of having the heat source in the basement.

Using to small a register can cause a problem with gravity heat.

Consider a set back thermostat on the main furnace this way you can cut the heat back automatically during the day.

NOTE LP is cheaper than oil because LP does not contain as much heat value as oil. Look up the difference and you will see what I mean.

Burner oil number two is 140,000 btu per gallon

Propane is 91,600 BTU per gallon.

A huge difference.
This is why oil is higher

Thanks for taking the time to respond. I have set-back thermostats already. The problem is I don't want it cold when we get home just a moderate - like 63-65 temp. I can have the set-back thermostat take it all the way down to 50 degrees but then the furnace would just have to work that much harder to get the house heated up by the time we got home. The basement is such a small(er) area compared with the first floor - and it shares the space with the oil furnace so there is also residua heat given off by that - that it just seemed to make sense to share some of that heat with the first floor and turn off the furnace upstairs altogether. The LP heater in the basement wouldn't work very hard because it doesn't take much to heat the downstairs up and I would imagine that even if I put in floor registers to share the heat it would probably still not take alot of LP to keep it at 68 degree down there constantly during the day.

I have also seen floor registers that have fans built in to pull air up - not sure how well these work though. I guess maybe I should just pay someone to keep my woodstove going all day ! Anyway, any more advice appreciated and thank you for the response !

Heat will naturally rise, if you cut in some 14x6 floor registers at the perimeter of the first floor they would have to help, how much they might raise the temperature is a guess. Your idea is well worth trying, they do make floor registers this size with dampers to shut them off if you choose. Good luck, Mike

Thanks Mike - I figure it is worth the effort and the cost - I would probably have a carpenter do this job only because I have nice oak floors on the 1st floor and don't want to take a chance on screwing them up. It may not be *the* answer to keeping the 1st floor comfortable but I think it will help by distributing heat that is already produced by the oil furnace and heat that is produced cheaper by the LP heater. With heating oil closing in on $ 4.00 per gallon that would mean I would need a minimum of $ 4,000 worth of oil to get through the winter which is shocking --- not looking forward to this winter ! Thanks again !

Well the basement heats so easy now because you are using a heat source rated to heat 1500 sq feet and you are only heat 800. My advice would be to install a high efficency propane furnace. this may help cut some of the heating cost. Also, a big hit here (South eastern Illinois) is outdoor woodstoves, if you have the wood, they are very cheap to operate, and they heat you whole house.

How about this as a complex setup.

Install a bypass damper on the furnace. Protects motor. Once the bypass damper is installed, the rest can be tried with cardboard.

Close off all of the return air ducts except the ones downstairs. Let fan run all day for the trial.

If it works, then install motorized dampers on the return ducts. A differential thermostat that looks at "basement temp" - "house temp". If it is positive by some amout and your on LP and there is a call for heat, then run fan and close all the return air grills but the ones downstairs. You may not even need the "if there is a call for heat". That just puts an upper limit on the temperature, but this stat could turn on/off the propane heater.