I am the wife of reVision heat’s Managing Partner, Ryan Hamilton. I’m also big into design, technology and energy efficiency, which makes me a perfect candidate for a Nest thermostat. Don’t let my interests mislead you, Nest is really for anyone who wants a more efficient, easy to use thermostat.

It was also developed by former Apple engineers, so it has those sleek, minimal, Apple-esqe qualities to the design.

When I first heard about Nest, I was indifferent. It’s a thermostat. What’s the big deal? I knew that I hated our then-current thermostat (which was extremely unintuitive), but probably not enough to make a point to replace it. But the more I read about it and the more I saw it popping up in my Twitter stream, and on places like CNET and Swiss Miss, I knew I wanted one. Badly.

Ryan came home from work one day and informed me that he wanted to install a heat pump water heater in our house. His reasoning was so that we could turn our boiler off all summer long and derive our hot water from another source. Bingo. I made him a deal: if he got a heat pump water heater, I got a Nest. Soon after our water heater was installed, Nest arrived.

Ryan decided to leave the installation of Nest up to me. As I unpacked the entire box there were a few things that I was pretty impressed with. The first is that the box contained really everything you’d need to install a thermostat. The box included great documentation and a small screwdriver that has four different bits tucked away in its handle. I was also pleased to see that there were two different sizes of trim plates that could be mounted between the thermostat and the wall to cover the damage that your old thermostat leaves behind.

Before I could take our old thermostat off the wall, I had to turn off the power to the boiler. Then I popped the face of our old thermostat off and unscrewed the base plate that it was attached to. I was really hoping to be able to mount Nest directly to the wall, but no dice. Our plaster walls contained a junction box where the wires came through so I needed to use one of the trim plates included with the thermostat. You can paint these plates to match your wall, but I chose to use the smaller white one without painting it.

With every DIY home improvement project there is always something more to do than you have anticipated. When our wall was previously painted, the painting was done around the thermostat cover so I needed to do a bit of touch up work to the wall prior to installing Nest. Once the paint was dry, I attached the metal plate included with Nest, the trim plate that I chose to use, and the base that Nest attaches to. I ran the wires through the center of it all and made sure that it was level. The Nest base has a built-in level so you can make sure the plate is straight prior to finalizing its placement on the wall.

Nest provides you with labels that you can place on the thermostat wires, but ours were already color coordinated so I didn’t end up using the labels. Nest also doesn’t require a jump wire like our old thermostat did so I just placed the red and white wires where they should go, and after popping the Nest itself on the base and kicking the power back on, I was done with the install.

Once the Nest comes on it wants to connect to your wi-fi. It will show a list of available networks in range and using the dial, you can select which one you want to use. This was the only issue I ran into during installation: the connection to the wi-fi kept failing even though the network and password were correct. I ended up typing in the network name, telling Nest the format (WEP/WPA/WPA2) of the router password, and re-entering the password. Once I did that, it connected with no problems.

Nest will then ask you a series of questions including what the lowest preferred temperature in the house should be while you’re away. You can also turn “Learning” on and Nest will begin learning your schedule.

Nest has also developed apps so that you can access your thermostat remotely. There are iPhone, Android and iPad apps available. Say you’re out for the afternoon and forgot to turn down the thermostat. No worries, you can do it on the fly. You can also warm up the house prior to your arrival and Nest will tell you how long it will take to get the house to the desired temperature. This ability is one of the things that makes Nest so great. This feature comes in handy if you’re away for the weekend and want the house to be toasty warm when you return.

We have only been using our Nest for about two weeks. The apps and the Nest itself will report energy usage, but it’s still too early for us to compare our current oil consumption to our typical past oil usage.

Overall, I’m extremely happy with our Nest. It is much more intuitive and easy to use than our last thermostat, it has a beautiful interface, it looks great on the wall, and the ability to access it remotely is a huge plus for me.

To help you better understand the differences between PowerSaver and PACE, we are posting highlights of the PowerSaver program with notations on how it is different from PACE, listing the qualification guidelines including what reVision heat solutions qualify, and providing Efficiency Maine’s nifty comparison chart for you to print or download to your computer.

Highlights of the PowerSaver program:

• Available to anyone in the state if they qualify (PACE in select municipalities only)
• Loans up to $25,000 ($10,000 more than with PACE)
• Loans smaller than $7,500 (PACE starts at $6,500)
• Fixed 4.99% APR (same as PACE)
• Loans up to 15 years or 20 years with solar energy (PACE only up to 15 years)
• Loans under $7,500 do not need equity or to be secured to property and may not require energy audit (PACE must be secured to property & require energy audit)
• PowerSaver loans are not transferable upon sale of property while PACE loans are.
• Residents will benefit with at least 20% in Energy Savings

Who qualifies?

• Owner occupied single family detached residence (PACE can be used by for single family residence or apartment buildings with 1-4 units)
• To qualify home owners need as much equity in home as they want to borrow plus a 660 credit score or better and a debt to income ratio of 45% (PACE based on home equity but credit score not used)

What reVision heat solutions qualify?

• Natural Gas Conversions
• Air Source Heat Pumps
• Heat Pump Water Heaters
• On Demand Water Heaters
• Smart Controls

PACE vs. PowerSaver Comparison Chart

Want to print the comparison chart? Click the image above or this link: PACE & POWERSAVER Comparison Chart, then print or save to your computer for future reference.

Heat Pump Water Heaters have been available since the 70’s.  reVision heat installed our first HPWH over a decade ago, but recently there has been a surge in new offerings to the market place.

What should you look for when purchasing a Heat Pump Water Heater?

reVision heat has installed at least one of each brand on the market, so we have lots of firsthand experience with what works and what doesn’t.  As with most things, the devil is in the details.  Choosing the right appliance for the application is half the battle. Here are a few things to keep in mind:

Sizing

Heat Pump Water Heaters recover slowly.  An on demand water heater makes between 3 to 8 gallons per minute.  An oil boiler makes 3 to 5 gallons of hot water per minute, and if it has a tankless coil, there is a huge mass of steel and water maintained at 180 degrees ready to provide you hot water.  Resistive Electric Water Heaters make about ½ gallon of hot water per minute, heat pumps make less.  As a result of their slow recovery, it’s very important to size the Heat Pump Water Heater appropriately.  All Heat Pump Water Heaters have back up or secondary electric elements.  Most systems, with the Stiebel Eltron being the notable exception, are digitally controlled, so you can set them to heat pump only, hybrid, or electric only.  If you’re going to all the trouble of installing a Heat Pump Water Heater, you really don’t want it running on resistive electricity at all.  We always recommend turning the electric off, and sizing the system appropriately.  The average American home uses 64 gallons of hot water a day, split pretty evenly between the a burst in the morning and a burst in the evening.  The average American home, with 3 to 4 people, is well served with a 65 gallon tank.  That’s enough for an above average morning without being excessive.  If demand is really strong, with houses of 4 plus, or where there is a large tub that needs filling quickly, more capacity is required.  Households with 2 people are well served with a 50 gallon tank.

Fitting to the space

You not only need to fit the Heat Pump Water Heater into the space, but you need all of the appropriate clearances.  The heat pump draws air in, extracts heat and humidity, and pushes the now cooler and dryer air out the other side.  It’s important to follow manufacturer’s recommendations to ensure air isn’t being re-cycled into the unit, which would reduce the efficiency.  Also, it’s important to note that some Heat Pump Water heaters are designed to be serviced (others are not, which is an important distinction).  For those that are designed to be serviced, clearance above the unit is important, as that’s how a technician is going to fix the system if needed.

Noise

Heat Pump Water Heaters are not all quiet.  The one complaint that we get on occasion from our clients is the noise level.  A Heat Pump Water Heater is far quieter than an oil boiler, no doubt, but it runs for hours in the morning and hours in the evening.  Depending on other noises in the house, the proximity of the Heat Pump Water Heater to bedrooms and how much sound separation there is, they can be annoying.  Also, not all heat pumps are built the same when it comes to noise level.

Longevity

A Heat Pump Water Heater is composed of 3 primary parts that could fail:  the tank, the compressor, and the controls.  All heat pumps could experience controller failure and be repaired with relative ease provided you call the right technician.  A failure of the compressor or the tank will result in the unit being terminated.  If our refrigerators are any indication, the compressor should last a very long time.  If electric water heaters are any indication, life span of a glass lined steel tank should be from 10 to 20 years, depending on the “hardness” of the water, the temperature at which the tank is maintained, if there is a sacrificial anode and IF that anode is maintained.  Stainless Steel tanks should last much much longer than glass lined steel.  Most all heat pumps have a 10 year warranty, so at least that is covered.  The good news is that the payback of most Heat Pump Water Heaters is between 3 and 4 years, so even if they die right after the warranty expires, they’ve still paid for themselves.

Efficiency

Heat Pump Water Heaters use 1 unit of electricity to move between 2 and 3 units of heat into the tank.  The warmer and more humid the space, the higher the efficiency with which they function.  Energy Star lists each Heat Pump Water Heater with an “Energy Factor”, which is a good way to gauge the efficiency of various units.  The Energy Factor is essentially the efficiency that the unit operates at for a “standard” amount of demand, in Heat Pump mode only, after taking into account tank losses.  Most brands on the market score between 2 and 2.5 in the energy factor.  That’s a big spread, and our feeling is that if you’re going through the trouble of installing a heat pump, you might as well try to be on the top of the scale.  If you pay $200 extra for an extra .5 energy factor, it will easily pay for itself many times over.

Pulling it all together.

First and foremost, get a unit that is big enough to meet your needs WITHOUT needing any resistive electric back up.  Second, make sure it will fit in the space, and it will be in a space where it’s not removing heat from the house (basements or attached garages are perfect).  Third, make sure it’s quiet enough for your needs. Once you have identified all of these constraints, make sure it’s as efficient as possible.  Stainless steel is better than glass lined steel and digital controls are better than mechanical controls.

Brand By Brand.

Our overall winner is the Air Generate.  Air Generate is a company dedicated to Heat Pump Water Heater technology.  What we love about the Air Generate is that they have what is by far the quietest Heat Pump Water Heater on the market, the only stainless steel tank AND the second highest Energy Factor.  Coming in at 2.4, the Air Generate is just behind the Stiebel Eltron HPWH at 2.5.  The stainless steel tank comes with a limited lifetime warranty.  They have two sizes, a 50 gallon and a 65 gallon tank, as well as an add-on.  Unless you need more than 65 gallons of stored hot water, we recommend the Air Generate due to the combination of quietness, efficiency, and the Stainless Steel Tank.

If you need more capacity, go with the Stiebel Eltron.   The Stiebel Eltron Acclera is a great unit and its 80 gallon tank stores hot water at 140 degrees, so it’s effectively 100 gallons of storage.  The Stiebel Eltron has an Energy Factor of 2.5, which is the highest on the market.  At 68 dB, it’s one of the louder brands on the market, so bear that in mind when locating.  The tank is constructed of glass lined steel with an anode, and it’s designed for service.  The SE has analog controls, so you can’t turn on and off the Heat Pump easily.

Third Place goes to the State HPWH.  Coming in two sizes, the 60 and 80 gallon size, this is a decent unit.  Its 2.2 Energy Factor is a bit below the AG and the SE, but it’s higher than the Rheem and the GE.  It’s digitally controlled and has a glass lined steel tank with a 10 year warranty.  We still use the State if we really want digital controls on an 80 gallon tank; otherwise, there isn’t any reason to choose it over the AG or the SE.  The state has a lower efficiency and is louder than the Air Generate, and it doesn’t have a stainless tank.

General Electric makes a respectable unit, but limited in size and with a low efficiency.  The GeoSpring has only 50 gallon capacity, and its Energy Factor is only 2 so it’s really only recommended for smaller families.  Compared to the AG, however, it’s louder, less efficient, and has a glass lined steel tank.

There are a number of other units on the market, but none of them have much going for them.  Rheem and Rudd, two major U.S. water heater manufacturers both have a Heat Pump Water Heaters on the market, but they suffer from low efficiency and loud systems.

One of the indoor heating vents.

When the Merriconeag Waldorf School in Freeport, Maine initially planned on upgrading their Handcrafts building, they knew they wanted a super-efficient and easy to heat replacement on their 80 acre campus. They already used both natural gas and oil for various heating systems but wanted to try efficient electric heat or air source heat pump technology in their new 2,500 square foot building.

Air source heat pumps use the same technology as refrigerators for both heating and cooling. They are super-efficient and operate down to -17 degrees. In a building that is both passive solar and super insulated, air source heat pumps are the perfect fit.

reVision heat was one of the contractors requested to place a bid on the air source heat pump heating system for Merriconeag. During that time, Pat Coon, co-founder of reVision heat, picked up on an error that would eventually save the school $10,000 in installation costs.

“reVision heat’s confidence, experience and intimate knowledge of heat pump technology provided the leverage I needed to get approval and funding for our heating system.”  ~Chris Gormley – Project Manager

Two outdoor condensers in the back of the building.

Pat recognized that the heating system was spec’d for summer usage, something that the school did not require, and called for a large cooling load. Once the extra cooling load was removed from the specs, the system was downsized and reVision heat was selected as the installation contractor. Two Hyper-Heat Mitsubishi air source heat pumps were installed along with resistive electric backup.

Kids enjoying a music lesson in the Handcrafts building

The Handcrafts building opened for operation in January 2012. At the time of our visit, we learned that the school is on track for significant monthly savings in their energy bills. The  electricity usage for the new 2,500 square foot building was about the same as the old 1,500 square foot building’s usage. The old building also used oil for heating, which is no longer a factor in the new building. It is estimated they will save over 28% per month on heating expenses but won’t know the full savings until they have more data.

The building itself is spectacular. Walking inside is like stepping into a room filled with sunshine. It’s no wonder the children are comfortable and happy there. On the day we visited, the temperature outside was a chilly 45 degrees but the inside temperature was 68 degrees. Will Hight, the school care taker, said that even on the coldest nights of the year, the resistive heat backup has not been needed. The indoor temperature is set for 65 degrees morning and night so there are no fluctuations in temperature which might cause cold spikes or make the system over work. Overall, Hight has been happy with how well the air source heat pumps are working and looks forward to reviewing the energy savings at the end of the heating season.

If you would like more information on air source heat pumps, we offer the following resources.

Demystifying Heat Pumps
I Thought Heat Pumps Didn’t Work in Maine
Freeport School Saves Before & After with Air Source Heat Pumps
Merriconeaq Waldorf School Photo Gallery
Air Source Heat Pumps
Heat Pump Water Heaters
Which Heat Pump Water Heater to Use

Part 1: showcases Kevin Butterfield’s 6 unit apartment building where he slashed his heating costs in half by switching to natural gas.

Part 2: discusses the concerns regarding the Omega Flex product, one of the major brands of Corrugated Stainless Steel Tubing or CSST.

In regards to your Omega Flex concerns:

The reVision heat difference is that everything is installed to the highest standard of safety and quality; one more reason to have reVision heat help you on the road off oil. If you have any concerns about the installation of Omega Flex in your home, we would be happy to inspect it to ensure that it is installed according to code and the manufacturers recommendations. Please contact us with any questions or concerns you might have.