I'm buying a new house that has a Bryant oil furnace with conventional air conditioning. I only casually looked at it, but tomorrow afternoon I'll be making a much more detailed inspection of the unit as well as trying to fire it up. The indoor unit looks beautiful, but the condenser looks 20 years old. The house was built in 93 so it's very likely the system is original. The house is a bank owned property so there is no history with the house.
I was thinking of adding a heat pump to the system and running dual fuel to save costs. Right now the unit will cost about $32 per million BTU output where as a heat pump will be about $18. Based on degree days if I switch over at 40 degrees to oil I'll have an average cost of about $20 per million BTU. If I can find electric for cheaper than Peco I'll do even better.
The ductwork is fiberboard and they used an uncased coil and used the fiberboard plenum to house the coil. I was going to cut the fiberboard up high enough and slide in a cased coil above the furnace. I normally work on heat pumps with electric backup or natural gas furnaces. This will be my first oil/HP hybrid. I'm looking for some pointers so I get the best efficiency. For one I saw that there can be an issue with the temperature rise when in defrost when running the oil furnace for heat. I saw that I could run a temperature limit switch or possible space the coil further away from the unit. Is the problem the temperature load on the coil when it's in A/C mode or is it the combined temp when it exits defrost and begins producing heat?
What thermostats would you recommend? I'd like a 7 day programmable with an OAT sensor and a lockout so I can prevent the oil from coming on when the temperature is above say 40 degrees outside. Will that cause the unit to send cold air out the ducts if it goes into defrost mode? Or would the oil kick in then? Can/should I put an electric coil in for use with defrost or is that getting too complicated?
Another option would be to simply rip out the oil furnace and go with all electric. The cost per million BTU would be slightly higher at around an estimated $22 based on the DOE calculator but it's not that far off and it's certainly cheaper than the oil costs. Lastly, since I have propane for cooking I could convert to a high efficiency propane furnace with HP and split the cost difference and be at about $21/million BTU.
i'll have specs, pictures and more information tomorrow afternoon when I do my inspection and I'll post them here.
EDIT: I can add that it has a Beckett burner with an outside combustion air setup.
Until then, Thanks
I was thinking of adding a heat pump to the system and running dual fuel to save costs. Right now the unit will cost about $32 per million BTU output where as a heat pump will be about $18. Based on degree days if I switch over at 40 degrees to oil I'll have an average cost of about $20 per million BTU. If I can find electric for cheaper than Peco I'll do even better.
The ductwork is fiberboard and they used an uncased coil and used the fiberboard plenum to house the coil. I was going to cut the fiberboard up high enough and slide in a cased coil above the furnace. I normally work on heat pumps with electric backup or natural gas furnaces. This will be my first oil/HP hybrid. I'm looking for some pointers so I get the best efficiency. For one I saw that there can be an issue with the temperature rise when in defrost when running the oil furnace for heat. I saw that I could run a temperature limit switch or possible space the coil further away from the unit. Is the problem the temperature load on the coil when it's in A/C mode or is it the combined temp when it exits defrost and begins producing heat?
What thermostats would you recommend? I'd like a 7 day programmable with an OAT sensor and a lockout so I can prevent the oil from coming on when the temperature is above say 40 degrees outside. Will that cause the unit to send cold air out the ducts if it goes into defrost mode? Or would the oil kick in then? Can/should I put an electric coil in for use with defrost or is that getting too complicated?
Another option would be to simply rip out the oil furnace and go with all electric. The cost per million BTU would be slightly higher at around an estimated $22 based on the DOE calculator but it's not that far off and it's certainly cheaper than the oil costs. Lastly, since I have propane for cooking I could convert to a high efficiency propane furnace with HP and split the cost difference and be at about $21/million BTU.
i'll have specs, pictures and more information tomorrow afternoon when I do my inspection and I'll post them here.
EDIT: I can add that it has a Beckett burner with an outside combustion air setup.
Until then, Thanks
I haven't looked at the cost difference between electric/oil/propane/HP hot water - yet... There's an electric tank there that works.
