Ten years ago, my husband and I signed a mortgage for a 150-year-old farmhouse with a little rental cottage. We set out to be responsible landlords, good stewards of the land and our historical houses. Part of that responsibility has meant tackling building energy use. Our energy efficiency measures started when we arranged energy audits on the house and, later, the cottage. In our house, we blew insulation into the attic and walls, sealed air leaks in our basement and invested in quality windows. (You can find additional energy saving tips here.)
Since making these renovations, our house has become more comfortable and it’s great that our bedroom windows no longer sprout interior icicles in the cold New England winter. A few years later, we took another step toward sustainability and installed a ground-mounted solar array— the orientation of the roof and shade cast from mature silver maples made the roof less than ideal for solar panels— to generate as much electricity as my family uses.
This winter, an HVAC professional came to service the furnace in the cottage and he told us it was one of the oldest furnaces he services. At that point, I knew it was time to start exploring new heating options.
Through my research, I learned that an electric heat pump can dramatically reduce home heating costs. An analysis by Rewiring America found that electric heat pumps are less expensive for the average household than traditional heating equipment that use electric resistance, propane or fuel oil. And because heat pumps can run on renewable energy like the solar panels in our yard, they pollute less than the average furnace— let alone the average centenarian furnace.
So, here’s the play by play of my journey to install a heat pump heating/cooling system in our cottage:
I researched and called eight local HVAC companies for bids on the job. I received three estimates. Of those, I would have happily worked with two of the installers because they were responsive, professional, able to communicate with a lay-person like me relatively clearly, and cost competitive.
However, these two installers gave me oddly vague and contradictory information about the availability of rebates. It remains unclear to me to this day. One said I could only get a rebate if we ripped out the old fossil fuel furnace, and the other said we could only get the rebate for the heat pump if we kept the oil furnace and used the pump for supplemental heat.
For now, we’ve gone with the latter approach and kept the old oil furnace and the oil tank in the cottage basement. Although we fully expect the heat pump to keep our tenants comfortable, we’ll probably tear out the furnace and complete our journey to a fossil fuel-free rental property at some point in the next few years. Between the time and cost investments and the maze of different incentives programs, tackling sustainable renovations in phases works fine for us.
Jun 15, 2021
We sign the contract for the work and the installer orders the parts.
July 7, 2021
7:45am - Workers arrive. Three trucks and then two others for the electricians. A packed driveway and all for our tiny cottage!
I give them a tour of the site and walk through the job to make sure we’re all on the same page before the workers unload equipment from the trucks and begin assembling and installing the heat pumps.
All morning, the work site felt quiet and productive. Electricians were preparing to connect the incoming equipment to the electrical panel, installers set up the platforms that will hold the external portions of the heat pumps, and others assembled the heat pumps themselves.
4pm - The workers wrapped up for the day and the external units, two interior heads and wiring is in place. The external unit in our kitchen was also installed.
July 8th - I took the kids to camp today and worked outside our home, so I missed the installation play-by-play, but when I got home, the heat pumps in our house and the cottage were installed! Some pictures below.
I’m still familiarizing myself with all the controls— including fancy infrared sensors between the mini split head, the thermostat and the integration with our furnace— and the difference between using the thermostat versus the controls on the heat pump itself. Those manuals will be some good bedtime reading, and I plan to have the next 20-25 years to practice.
With mild temperatures for the next few weeks, we won’t get a full test of our system. But our tenants did text us and say “The mini splits are great! Sooo quiet! I am so happy with them!”. We plan to run our heat pump mostly on extremely hot or extremely cold days to take the edge off in our kitchen and living area.
July 19th - The weather has become swampy. It rained 4.5 inches last week and everything is soaking wet. We came home from vacation to find mold on the cushions of our kitchen stools. Yuck! Enter our hero: Heat Pump! We’ve put it on “dry” mode and it’s been doing a great job pulling moisture out of our living spaces. So far, it’s passing the test.
August 12th - It's hot! 94 degrees in Amherst today, but with the humidity my weather app tells me it feels like 106 degrees. Ugh. I'm out of town and missing the heat, but I got this message from my husband, who is holding down the fort at home: "Really appreciating our mini-split heat pump on these brutal days. I slept downstairs on the couch last night. Best night of sleep all week. I've found that the "Econo-Dry" setting, not even an explicit "cooling" feature, does the trick, keeps the house at a dry-ish 75 degrees. The drain hose out the back wall of the kitchen drips like a turbo-charged maple tree tap on a warm day. I've thought about collecting the water to see how much there is, but it must be gallons over the course of a day, pulled out of the air inside our house." Thanks again, heat pump. The furnace definitely isn't doing that and it's great not to have to install the loud and inefficient window air conditioner.