Viewing a single comment thread. View all comments

UniWheel t1_j0960l3 wrote

You mini split is probably cheaper for maintaining temperature most of the time.

Your boiler may be cheaper for raising the temperature, or on the days when it's coldest out, which is when the mini-split's effective efficiency (of "pumping" rather than "creating" heat) drops from almost 400% down towards 200% and may no longer overcome the inefficiency of the original electric generation (which in MA is largely from burning fuel)

Either way key is also going to be using only the heat you absolutely need in the parts of the house where you need it. Though do be careful if you close part of a building off entirely to consider the risks of pipes freezing - including heating pipes. Hot water heating systems often control the return, actually, so if they freeze they'll happily send huge quantities of heated water into the break.

18

wkomorow t1_j09j1hw wrote

Great advice. I leave my main thermostat at 61 in the day and 59 at night. My living room splits (where I spend most time during the day) is set at 65 during the day and off at night. My bedroom split is off during the day and set at 63 at night. With humidifiers, it is quite comfortable. I added a zigbee temp sensor in the basement to warn me if the temp in the basement goes before 40 at night.

6

UniWheel t1_j0c8jnb wrote

I'm personally trying to avoid running the heat pumps (mini-splits) during the coldest part of the 24-hour cycle, because the colder it is outside, the more energy required to produce the same amount of heat.

So I've been turning them off when I go to bed, and then trying not to turn them back on again until mid/late morning when it's had a chance to warm up outside or at least the sun is on the compressor. It's close enough to the bedroom window that I can just hear it in the silence at night, and it's the sound of money being spent.

Many would argue that you shouldn't adjust the setting on heat pumps at all, but just leave them. I don't quite agree with that, because the same heat is more or less expensive during the colder/warmer parts of the outside day, and my home cools slowly enough that I can meaningfully average those.

But I would argue against turning up heat pumps "for comfort" during a particular part of the day, especially if that's a time when it tends to be cold out, like first thing in the morning - so for someone who's leaving the house to go to work or school, trying to wake up to a warm space is fairly expensive.

2

wkomorow t1_j0cckbu wrote

Thanks, I just got my monthly gas bill $86 for furnance and indirect water heater. It was $207 last year this time. Heat pumps really help. My electric went up to $68, it was $47 last year this time, and last month it was $18. I am on a city electric pool, so my rate is .09 per kw, which helps There wasn't a lot of really sunny days, so my panels could only do so much. Snow covered them for a day even though it was sunny after the last storm. I may just set my main thermostat to 61 and keep it there and not run the splits in the bedroom. My bedroom is on the second floor of a cape so it accumulates heat from the first floor. Having a warm mist humidifier really makes a big difference. I also put down the shades and close the drapes before sunset and open after sunrise. (They are automated, so I really don't do much.) And I keep the door closed on rooms I am not in.

I appreciate the advise, Jan is always the real test.

1

UniWheel t1_j0d2bn3 wrote

>I am on a city electric pool, so my rate is .09 per kw

Damn you are lucky :-)

With those rates, I'd use the heat pumps exclusively.

2

wkomorow t1_j0d6kcx wrote

Don't know what happens Jan 2024, but Pittsfield contracted with Dynegy Electric Services a fixed rate at $0.09603 per kWh for all rate classes for 36 months (January 2021 to January 2024). The mayor deserves a lot of credit for this deal. Great Barrington just went wit Dynergy and their rate is $.22. Salem is locked in at $.11 to the end of 2024.

3

No-Bug3247 t1_j174mf0 wrote

Just kidding but who are you people with 63F? My wife won't be comfortable until the house is at 75F!

1

wkomorow t1_j187is1 wrote

At night, I can not sleep if it is warm. During the day, I wear a pair of chunky socks over my socks and typically a chunky sweater or sweatshirt. I hate hot weather. In the summer, I garden before 9 AM because I am worthless once the temp gets just south of 80. I run the air conditioning a lot in the summer. With the splits and solar (which I own not lease), it costs me nothing for the air condition. Normally my electric bill shows a credit from Mar-Nov.

1