On Wednesday, May 10th, I got a frantic phone call from my wife about 5pm that our basement had flooded and there was water everywhere. I was at the airport in Austin, Texas, on my way home from a work trip. It would begin a 6-day adventure to replace the gas hot water heater with a heat pump hot water heater, sometimes called a “hybrid electric water heater”. I hope there are some lessons in here that will help others make this upgrade, and it also poses some questions about how we can make this process easier.
Prevention
The first thing to talk about is prevention. Everything would be easier if you could plan the upgrade and not deal with a flooded basement, ruined carpet, no hot water, etc. The water heater was 19 years old. I knew it was old. I didn’t know how old, but I should have. I thought it would give some kind of warning. Brown water or something. It didn’t.
I had two water sensors in the basement for exactly this purpose. One next to the water heater, and one behind the washer about 20 feet away. They are — err, are supposed to — tie into my home automation system which is Home Assistant. The one next to the water heater alerted at 7:30 am. Unfortunately, I didn’t have the alerts set up properly in Home Assistant, so I’m sure it beeped but no one heard it. At 1:30 pm water must have reached the washing machine. The other sensor alerted. My wife got a push notification about a water leak. She texted me asking what it meant. I was in meetings, she was in meetings. She didn’t go down there until 5pm, but the water had reached half way across the room by 1:30. Lesson: get water sensors and make sure they can alert you properly.
Remediation and Insurance
By the time I got home around 10pm, very kind neighbors had helped her turn off water to the water heater, turn off the gas, drain the tank bucket-by-bucket, and clean up a lot of the water. We’re in their debt.
The next morning I called the insurance company and started a claim. (I barely knew who it was but found it on some mortgage docs). There’s a $1,000 deductible, which they said is standard. They have a list of mitigation companies. Apparently this happens a lot. After some very quick googling we picked one off their list and they came that day. Their job is to get rid of the moisture so it doesn’t turn into mold. They thought they could pull back the carpet on the edge and put the fans around the edges. That wasn’t enough. They wound up cutting out half the carpet. Because they had access to both sides of the affected walls, they didn’t feel the need to cut out the wet drywall. They left about 8 fans and 2 dehumidifiers that ran from Thursday until Monday.
I would later find out that insurance won’t cover a new water heater in this situation, which is only fair. We’re still working through it, but it seems like they value the things were ruined (like the carpet), apply a depreciation percentage (for example saying the carpet was 5 years old out of a 10 year lifespan. Also seems fair), and pay out what they call a “recoverable depreciation”.
Plumbers
By this point I knew I wanted a heat pump hot water heater. In fact, I knew it standing in the airport. I haven’t been able to justify ripping out things that were working to make them more efficient. But I certainly had been planning to do efficiency upgrades every time something needed to be replaced. You probably know this by now, but a heat pump water is very efficient because it pulls hot air out of the room and turns it into hot water, running a compressor like an air conditioner or a fridge to do it. It has a resistance electric heater as a backup.
Thursday morning I called every plumber I have worked with previously. None of them could come until the middle or end of the following week. Finally, I called one of the big companies that a friend had used. They would come out the same day.
I also started working my way down the list of plumbers on Rheem’s site. I figured any plumber that went to the trouble of listing there and checking the box for “hybrid water heating” was someone I would like to talk to. I probably made 3 or 4 calls — googling reviews beforehand — before I found an independent company that would come out the next day, Friday.
The plumber from the Big Company showed up. They carry 50 gallon gas hot water heaters on their truck. If I wanted to replace like-for-like, we could have had the hot water back on Thursday. I think my wife had done a little googling on heat pumps and understood my interest and was on board, even if we had to wait longer. “It’s a 15 year decision” I said over and over. Big Company guy quoted 50, 65, and 80 gallon options for gas and hybrid electric. (I’ll get to the $ numbers a little later).
When Independent Company guys showed up the next day, it was a similar conversation. In both cases, they were lightly pushing the gas version. “There’s a real flame down there”. “The hybrid electric is way more expensive. What’s the payback period versus gas? I bet it takes a long time to pay back.” I would mention decarbonizing the economy in my response, but it didn’t seem to resonate. The customer is always right, and they were both willing to do hybrid electric, so it went fine.
Choosing a water heater
I had started googling what model I wanted on Wednesday night. Rheem and A.O. Smith seem to be the two big options for hybrid hot water heaters. Home Depot sells Rheem. Lowe’s sells A.O. Smith.
I have an unusual additional requirement on many home things which is I want them to integrate with Home Assistant natively so I can monitor and control them with everything else in the house. Rheem devices have WiFi and an “EcoNet” app which has an easy existing integration with Home Assistant. For A.O. Smith there are some vague threads where people express interest in reverse engineering the protocol A.O. Smith uses to issue commands to water heaters. Not promising. I decided on Rheem.
Big Company only installed A.O. Smith, which they said about five times they thought were the best. Independent Company had a slight preference for A.O. Smith, but was willing to install whatever I wanted. The Rheem 65 gallon “Performance Platinum” is $2,267 at Home Depot. The “ProTerra”, the next model up which includes a leak sensor and automatic shut off, is $2,491. The A.O. Smith’s are about the same price. The plumbing supply stores, which is where the plumbers shop, charge a couple hundred more.
Unlike the gas hot water heaters, plumbers need to call around and find the right model from their supply stores. When Big Company called me on Friday afternoon to try to close the deal, he didn’t know if or when he could get one. He promised to call me back later Friday afternoon once he found one, but didn’t end up calling me back until Monday, saying he had finally found one and could install it on Wednesday. I had already decided to go with Independent Company.
It took some negotiating, and by this point I had multiple quotes. The price we agreed on (both the unit and installation) was $5,500 for the Rheem 50-gallon or $6,400 for the 65 gallon. I was tempted, and asked, if I could buy it at the plumbing supply store and they could install it for me. They didn’t want to do that. We were on for a Tuesday installation, but I had to have the electrical done.
Electrical
One of the “downsides” of the hybrid electric water heater is it needs electricity, obviously. Whereas the gas line is sitting right there next to the defunct gas heater, I needed a new dedicated circuit for the new hot water heater. We have an old house — built in 1936 — and a finished basement, so it would be a chore to run a new circuit.
Big Company has an electrical division they push on you. Their electrician came on Friday (T+2) to give an estimate. We really liked the guy. He was great. But his quote was $2,000, though he came down to $1,600 as it was clear we weren’t going to bite. It became clear — and I’ve had this experience before — that the big companies pay their guys on commission.
I’ve done a bit of DIY electrical. I love wiring things, it’s just part of who I am. I’ve probably replaced a dozen light switches in the house with smart switches, including one or two three-way switches. And I’ve run a lot of low-voltage stuff, such as ethernet, HDMI, USBs, and coax through an old house. I try to draw the line at messing with the electrical panel itself. Also, my wife wanted a professional.
Friday night I went to Home Depot and got the wire - $300 for 100 feet of 10/3 wire and a 30amp breaker ($25). I got to talking to the guy in the electrical department. His family came from Serbia when he was a kid, and his dad is an electrician. He had confidence I could do it myself, but I got his number and said I might want him and his dad to come and check my work.
Saturday morning I spent 3 or 4 hours fishing the the wire through the ceiling across the basement. It’s a basement so there are some existing access holes. I’ve used the same path for a lot of the low-voltage stuff, so I knew the route. That part went great.
But it’s an old house. The top of the electrical panel was totally full of wires. There was no way to get the wire into the top of the box. I considered cutting holes in the drywall to run the wire down the side and in the bottom of the box. But there is wood everywhere. I was tired so I left the wire dangling in front of the panel and texted my friend from Home Depot. He would come with his dad first thing Monday morning.
When they showed up Monday morning they made quick work of it. His dad, as if by magic, moved the wire to the left side of the box, and in about 1 minute pulled the wire through a knockout hole I hadn’t considered. They were at my house about an hour asked for $180. I rounded up and it’s still the best money I have ever spent.
Install
The water heater install went well. It’s a big machine. Getting it down the stairs was harrowing but ultimately uneventful. They capped off the gas line, and put a cap in the flue.
One other thing to consider: just like an air conditioner, a heat pump generates condensate (water) which needs to find a way out. I have an air conditioner right next to the water heater, and it already has a pump attached. So it wasn’t an issue in my case but many people would need a pump and a way to reach the outside.
It was a full day job. They had three guys who were excellent. Certainly the highlight was connecting it to WiFi. One of the guys asked “what’s ‘M A C address’ mean?” That part I knew.
Takeaways
Here’s are the takeaways on cost:
$6,400 for a 65 gallon heat pump water heater, installed
~$350 in wire and breaker parts
~$200 to the electrician
Probably about $200 in tips along the way
Minus, and this is huge:
$650 in a D.C. rebate because the plumber is a DC Master Plumber
$2,000 (30% of the cost up to $2k) in federal tax credit, thanks IRA!
I think it would be easy to spend a lot more. The newest technology, lots of subsidies available, customers who can afford it — it is easy to see how prices could go higher.
And I certainly found the least expensive electric option that wasn’t 100% DIY.
The biggest obstacle to adoption of heat pump water heaters will be the inertia behind replacing a gas water heater with another gas water heater. Six days without a hot shower [at home] for a full family is a long time. The showers wouldn’t come on at all. The dishwasher didn’t work. I was dedicated to the heat pump, and my wife was on board. It’s easy to image choosing the easy road.
emergency situation and the 6 days this took.