kbeefy
Well-known member
Bought an old house in a place I've never lived before and am getting a little sticker shock from next months projected utilities cost.
Spring/summer/fall were all about $150/month. My property has 3 gas meters and 3 electric meters, one being commercial so $50 of that is just meter/service fees. It started getting colder last month and my bill was about $300. OK, I expected that.
After looking at the propane price thread I decided to check my price per therm ($0.90, not to bad) and noticed that 7 days in I've already used $100 of gas/electric and my projected bill next month is $800+. Whoa. Even in AK with high electric bills $400 combined was high.
So, I had been intending on adding a mini split or two to replace a couple ancient window/wall mounted AC units that really didn't do the job anyways. Now I've decided it would be best to make them ductless heat pumps, and winter bills are harder to deal with than summer heat so I'm not going to ignore it any longer.
My first question is what is a good load calculator to figure required BTU's for sizing a system?
This house was built in the '60s and is kinda unique. Is there a method to calculate from kWh/therms used? (I just realized Therms are based upon BTU's, so I could probably crunch these numbers. Not usefull for cooling though....)
I am looking to 'condition' about 1250 sq/ft upstairs and 600 sq/ft downstairs. Downstairs doesn't really need AC but some heat would be nice. Currently has baseboard electric heat.
Upstairs could use heat and AC. Currently has 1 wall mounted AC (12k?) thats probably 25 years old, 2 Natural gas furnaces and a bunch of electric baseboard heaters. The furnaces make plenty of heat but distribution is poor. The AC is just silly, it really only helps if your in the room its in while it's on.
That probably works out to more than one question, but heres my second question....
Multiple ductless vs multi-zone units?
I was originally thinking a single 30-40k multi head ductless, but reading a different thread suggested that may not be the most efficient or cost effective way to go. Both upstairs locations will have identical heating/cooling requirements, they are adjacent rooms and have identical construction, insulation and exposure.
Downstairs is a completely different environment, and was pretty comfortable without AC last summer (we had a brief period of 100, and 6 weeks of 90+... the basement didn't get over 70).
Spring/summer/fall were all about $150/month. My property has 3 gas meters and 3 electric meters, one being commercial so $50 of that is just meter/service fees. It started getting colder last month and my bill was about $300. OK, I expected that.
After looking at the propane price thread I decided to check my price per therm ($0.90, not to bad) and noticed that 7 days in I've already used $100 of gas/electric and my projected bill next month is $800+. Whoa. Even in AK with high electric bills $400 combined was high.
So, I had been intending on adding a mini split or two to replace a couple ancient window/wall mounted AC units that really didn't do the job anyways. Now I've decided it would be best to make them ductless heat pumps, and winter bills are harder to deal with than summer heat so I'm not going to ignore it any longer.
My first question is what is a good load calculator to figure required BTU's for sizing a system?
This house was built in the '60s and is kinda unique. Is there a method to calculate from kWh/therms used? (I just realized Therms are based upon BTU's, so I could probably crunch these numbers. Not usefull for cooling though....)
I am looking to 'condition' about 1250 sq/ft upstairs and 600 sq/ft downstairs. Downstairs doesn't really need AC but some heat would be nice. Currently has baseboard electric heat.
Upstairs could use heat and AC. Currently has 1 wall mounted AC (12k?) thats probably 25 years old, 2 Natural gas furnaces and a bunch of electric baseboard heaters. The furnaces make plenty of heat but distribution is poor. The AC is just silly, it really only helps if your in the room its in while it's on.
That probably works out to more than one question, but heres my second question....
Multiple ductless vs multi-zone units?
I was originally thinking a single 30-40k multi head ductless, but reading a different thread suggested that may not be the most efficient or cost effective way to go. Both upstairs locations will have identical heating/cooling requirements, they are adjacent rooms and have identical construction, insulation and exposure.
Downstairs is a completely different environment, and was pretty comfortable without AC last summer (we had a brief period of 100, and 6 weeks of 90+... the basement didn't get over 70).