Mar 31, 2014 - life    No Comments

A year with a heat pump

Here’s the TL;DR:

Heat pump: Fujitsu Halcyon 12RLS2 

Dealer/installer: Maine Alternative Comfort — they were awesome and I would totally recommend them and not just because I once got a credit for recommending them. Adam is more energy nerd than salesman (and that is a compliment!) and his crew was super nice, didn’t leave a mess or anything, and we’ve been very happy.

Price: $3000 before incentives, which were $600 from Bangor Hydro, $300 on 2013 taxes, and a $25 referral rebate from Bangor Hydro from referring a friend. Net cost: $2075.

Are we glad we did it? YES!

Our heating situation before the heat pump was that we have a Thermopride forced hot air furnace, that is relatively new (10 years) and really efficient, and well respected by our furnace cleaners. We have just one zone, and the thermostat is in the living room where we spend most of our awake time. Being conservative with the thermostat and liberal with the sweaters and fleece slippers, we had our oil consumption to under 400 gallons a year. In the ten years we’ve owned our house, though, the price of oil has almost quadrupled (I keep records – our first oil fill was at 1.57/gallon!) so we are always looking for ways to economize, even with what little we use. A few years ago, friends were getting rid of a propane fireplace, and we replaced a woodstove that we’d been advised not to use with the propane stove. We have a hearth, and it’s a direct vent stove, so we didn’t need the chimney (although we do have one in place, from the woodstove.) That kept us warmer, because we could heat the living room with it, and the way our house is laid out, the stairs acted like a chimney and pulled a lot of that warm air upstairs. However, we only ran the propane when we were home and in the room, because it is an open flame, and we are paranoid. Before we got the propane stove, we’d planned on doing pellets, but a con of pellets is that you need a place to store them, and that would be tough in our small house.

The heat pump came about when friends of my parents looked into one for a camp, and were impressed by the technology and the price, and in our area, they were offering incentives to install one. It happened pretty quickly — I filled out the form on the Bangor Hydro site for a heat pump rebate, and one was reserved for us, and then I had Adam from Maine Alternative Comfort come in to see if we could install one. His initial location idea was on the front of the house, but we were not comfortable with hanging it next to our windows, for aesthetic reasons. When he came back and said it could be installed on the side, we went for it.

The install took a little longer than most others, because they were using our house to show some people from the state (I think?) how an install works and why it would be good to fund incentives for more people to install. (I think, I know we were being used as sort of a “demo house” and that the explaining took longer, but I was fine with that.) Usually, an install is done in half a day. The install process was pretty straightforward – one team installed on the outside, another guy worked on the interior mounting, and an electrician ran wiring to our panel. You do have to have room for a 220v outlet (? Again, I’m fuzzy on the exact language, but I know that we had room on our panel, and sometimes people don’t have room  and it’s more electrical work.) We had ours mounted in the living room, on the same wall as the propane stove, just the other corner. There were some concerns about it being close to a propane tank, which we removed, because the heat pump was essentially going to replace the propane stove for heat. (We have kept the tank and the stove hasn’t moved, though, as it doesn’t need power to run it is our third form of heat, and if we ever needed it, it would be because the power was out and the heat pump doesn’t work without power!)

Once it was in, we shut down our furnace for the year. It was April, so only slightly earlier than normal. One of the perks of a heat pump over a pellet stove is that it also provides air conditioning, which is something we’d never had. Even with hot, sticky newborns clinging to my chest through a Maine summer, we only relied on fans, and it was awful (Dave wouldn’t say so but he also wasn’t the one with the newborns sticking to him.) The first time we used the AC, was  during the first hot spell and Dave had been dismissive of it as a feature, so I was certainly not going to be the one to try it out. I went out for a bit on a hot day, and when I returned, I opened the door and the whoosh of cool air was shocking. Dave was converted. We didn’t run the AC all the time, just when we had to, and interestingly, our power bill didn’t change hardly at all! In fact, it went DOWN in July. I now wonder of the fleet of fans costs more than the heat pump’s AC does.

For heat, it’s been great. It’s been a very, very cold winter, and the pump will run into below-0 temps, but it is definitely working harder and not getting as warm then. Our biggest concern is our basement pipes, the one place the heat pump does not reach. We have temp sensors all over our house, and know that our basement sill can get to below freezing when it’s bitter cold out. When it gets close to freezing, we bump the furnace on to warm the basement. We’d like to insulate that cold wall by pipes a little better and see if that helps for next year, since it does seem strange to use oil to heat one space when we are humming along at 68-70 upstairs without oil. One challenge was accepting that it’s more efficient to set-and-forget, as opposed to tweaking out a custom program on our old thermostat to conserve energy. It operates very quietly, especially the milder it is. When it’s very cold, you can hear it working harder, but in general it’s a quiet white noise when you can hear it. Our house is 1000sf above grade, and set at 70, it keeps the first floor around 68-70 and the upstairs bedrooms, about 64 – much warmer than we’d allow on oil.

So, what does it cost to RUN? Well, back to the spreadsheets again. (And by the way, Emera Maine/Bangor Hydro has a great feature where you can see data at several levels – daily, weekly, monthly, annually, AND compare it to other variables, and see the temps for those times as well – definitely worth checking out, even if you don’t have a heat pump in your future.) For instance:

Here’s a comparison between 2012 and 2013. The heat pump was installed in April, and we didn’t turn our furnace on until near Christmas, I believe.

yearly

Now, look at Jan-March, which anyone around here will tell you has been cold (and the graphs agree). The blue and gold are 2014 numbers, red and green are 2013. So, yes, we are using quite a bit more electricity.

13_14comparison

 

But here’s the daily view, from a random day in March that was about the same as the year before:

Dailyusage

The temps were still colder, but there were parts of the day last year where our energy use was more than double from THIS year. I have no idea why – maybe I did laundry, for instance, but it provides a decent weekday comparison.

Dollar wise:

Well, I have a spreadsheet. 

This winter is probably a worst case scenario for running a heat pump because of the prolonged and extreme cold. If I look at the average monthly temps, for instance, January: in 2012 it was 23, last year 21, and this year 18. February: 27,24,21. and March: 38, 34, 18 (!!!). So, basically our March was like a cold January (isn’t that depressing), and our usage reflects that. If I assumed that March was 34, on average, that puts us closer to December 2013’s average, where we only spent $125 on power. kWh-wise, we should see less usage in a more ‘normal’ year.

On that spreadsheet you can see our power use by month for 2012, 2013 and current 2014 figures, along with average monthly temp. (Thanks, Emera!) While we’ve definitely spent more on power (and I’m not accounting for power supply rate increases if they’ve happened, etc) I look at it as gallons of oil. The most we spent beyond past bills is $139.39, and we last got oil last month. (We were actually worried that our gauge was wrong, and with the unrelenting polar vortex bearing down on us, we decided to get 100 gallons to be safe – we’d planned on waiting til June to fill up) We paid 3.89/gallon, so if I calculate that extra power expense as oil, we spent 35.8 gallons of oil on electric. Assuming we use our super frugal estimate of 350/gal a season, and we only heat from October-April (6 months) then that means we would normally use 58.3 gallons of oil per month, so we are ahead by more than 20 gallons. AND we are warmer. (I’m not even factoring in propane for the fireplace in these numbers, which made us warmer, but also cost over $100 for last winter to do so. (And remember, last winter was warmer!)

So, that is my super-geeky number crunching on our heat pump purchase. I’m not even calculating carbon footprint, etc etc into that, just the bare numbers. I figure our ROI will happen next year, since the install cost 520 gallons of oil (so about a season and a half), but comfort wise I think we were pretty close to ROI when we first fired up the AC part, long before we got to heating season!

Also! We were slackers on cleaning the filter and when Dave finally did (months into using it) the difference was astounding, so now he does it every 2 weeks, like clockwork. The manual says to do so, but it really HELPS to do so. Often manuals say to do lots of things that don’t make a difference, but cleaning the filter is easy and helps efficiency, so do it.

 

Got anything to say? Go ahead and leave a comment!