Hybrid heat pump water heater

Only two of us (plus four furries), so that does make a difference too.

BTW, dense foam is a better insulator (R-7/inch vs 3.5-4)), which is why we used that in our wall construction instead of fiberglass. Unfortunately, it’s also much more costly and virtually impossible to add as a “blanket”.

I’m well aware of the advantages and disadvantages of foam as I’ve had probably hundreds of thousands of cubic feet sprayed. Just about all block buildings these days like schools, jails and box stores have it.
I’m not a fan in residential for one reason, moisture. Where it’s made of plastic and is waterproof, it can’t breath. Which leads to rotting and termites. There is a product called Dryvit that replaces stucco. It came out late 80’s and was extremely popular in million dollar plus homes. After about 10-15 years the troubles began and there were a lot of ruined homes. They have redesigned the installation to mitigate these issues so it’s less likely now. But I know a couple people with houses less than 10 years old now with moisture problems after having spray foam done. Now I don’t know how good there installer was and if everything was done properly but I’m using cellulose in the attic and fiberglass everywhere else for now.
We didn’t have the same issues with block buildings and foam. It also wasn’t the foam that sprays “on”. This type sprays “in” and I think has less density to it.
I’d say dry climates don’t ha e problems. Arkansas and Kentucky are both really humid.
We also had that foam used in shipping stones to us. They would wrap the limestone or cast stone in crates with each piece wrapped in plastic. They would then close the crate and spray the foam in holes to fill the voids. Talk about a job getting them out. The foam is tough stuff. The stones were coming from England so they had to be secure.

@andy
I’m glad you put the name of your water heater
Up. I just went and read about it and it I’m thoroughly impressed.
I was thinking you had a Cadillac of heaters but it’s more like a Rolls Royce. Others can see the brand and model and know what to look for when they need one.

Yes indeed, spray foam has to be done correctly, on properly prepared surfaces. Additionally, since it does dramatically reduce air infiltration, care has to be taken to insure fresh air properly de-humidified (ERVs), even here in NH which is pretty dry. Our home (10 years old) uses a combination of 2” dense foam and 6” of compacted cellulose, providing a R-50+ wall. Ceilings have 3” more cellulose. Blower door testing shows virtually no air infiltration and energy costs for our 100% electric home are pretty reasonable, even with local high prices.

This (and lots of other details) investment in energy conservation was why I was so interested in Sense when I saw it featured on a TOH show two years ago. Unfortunately, it’s inability to function properly in a “noisy” (constant pressure deep well pump) environment has limited its usefulness detecting most of our home…including the noisy well pump itself.

Best of all, payback was pretty compared to local home store models….didn’t have Sense back then, but other indications were less than two years to cover the difference in cost. Sense has detected it and seems to be tracking run time pretty accurately. I’ve cross checked against my Welserver system for run times and power draw shown by Sense matches what I’ve measured by ammeter/voltmeter quite closely…

Sounds like your buttoned USA s right as possible. My blower test wasn’t that good unfortunately.
I see a lot of problems with sense and the well pumps.
I can’t help be wonder why people to move to “cycle stop valves” (CSV). They save more energy and have a proven record of reliability. I’m sure they are not as “noisy” also.

Hmmm, never heard of those…interesting. Maybe next time.

My variable frequency constant pressure pump is 500’ down the well and very expensive, so I’m stuck with it for now despite the fact that Sense finds it so “noisy” that it disrupts detecting almost all devices in my all electric home.

Seems to me that if Sense knows of devices that render their product pretty useless, they could tell people before they buy and invest all that time (and $) in trying to get it to work. Many products have disclaimers right on the top that say “not suitable for xyz situation”, nothing wrong with doing that.

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Their marketing is misleading in ways and too vague in others.

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So to get back on topic, has anyone’s heat pump water heater been detected? Mine hasn’t been found yet and the heat pump startup is sometimes conflated with my pool pump.

Mine has now been found, it is about 75% accurate comparing to the rheem app for just the heat pump. The element has yet to be determined, but it is usually confused with the dryer.

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Are you pulling ~400 watts?

Yes sense picks up the device at 338 watts. I think that’s low, it looks to be more like 380-390.

I just installed the Rheem 50 Gal Performance Platinum Series hybrid unit. So far I am running in energy saver mode. I had been testing the install of a 100 amp tankless unit and a small 12 gal tank for my retrofit recirculating system. The tankless kept going out so I switched to the Rheem which was available locally. Easy install and so far no issues.

This all to replace the 38 Gal Low Boy that was over 18 years old and could not support a family of four. The sense had picked up the original unit very reliably. I do hope the new system is detected at some point. I am really working to reduce all the always on and other devices.

That is a really nice water heater and a real energy saver. I believe the energy guide state about $425 a year but you’ll be lower than that.
If you use it with a recirculating system then I wouldn’t run it in energy saving mode as it will have to catch up too many times a day.
The water heater won’t affect your always on or shouldn’t.
You probably had a lot of scale in your old heater as I just replaced a 19 year old 40 gallon with a 40 A O Smith that is actually 37 gallons. I also have a family of four and it has no problem keeping up. I do keep mine at 135 degrees to combat legionaries which at that high a temperature also users less from the tank each draw.

Sam, I switched to Heat Pump only last night. I still need to run my condensate line so hopefully my bucket isn’t overflowing when I get home! Doesn’t seem to run that much though. I’ll hopefully know more once Sense identifies the unit. I recently had a missing component to my HVAC system identified by Sense 9 months after the rest of the HVAC was identified!

I don’t think there will be enough condensation build up to fill a bucket in a days time. The compressor and evaporators on them are really small. It does depend on the location and relative humidity. This time of year shouldn’t be bad. They only problem running in heat pump only mode is recovery time is greatly affected. It will take a long time to reheat water. The heat pump part of it is best for keeping water hot after the elements have done their job (depends on model).

I have my heat pump water heater on an HS110 smart plug (wired for 240) and it does great. It provides a very nice graph of the heat pump motor usage. It is only running in the heat pump mode. Recently Sense found one leg of the heat pump and called it Motor 2. The signal graph looks very trashy on the first part of the cycle and then a perfectly flat line on the last half. Looks like Sense is confused.

Isn’t that above the upper limit of an hs110? The thought did cross my mind as far as an hs110, since I run it in heat pump only, but if it ever runs both elements it could exceed the hs110s rating…

I have an AO Smith 50 gallon unit running only in the heat pump mode and it draws 428 watts when running, well within the HS110 ratings. We have plenty of hot water.

I also have an AO Smith HPWH that was only detected on one 120V leg, so I was getting half the readings. Detection was also missed a lot, so I got either shorter than actual runs, or no run detection at all. Worked with Technical Support and they finally advised that I delete it and let it be rediscovered, which I did. After a month it was rediscovered, but again only one leg, plus its reporting reliability was even more flakey. Tech Support’s explanation was that Sense was having a hard time detecting the off portion of this device and they were working on a new model. Since I was trying to get accurate measurements so I could calculate savings, I temporarily moved it behind an HS110 switch and am now getting reliable measurable results. Will run it that way for a month to get my readings and then will turn them over to the Data Scientists so hopefully they can better model this device. Interesting enough, this device starts out at 300 watts and slowly increases to 415. Also it looks like it is costing about a third of what my oil hot water heater cost to run. I’m also using the HS110 on a lot of devices that Sense just can’t manage to detect, like my refrigerator and washer.