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Heatpump water heater etc....

I recently bought the Rheem heat pump water heater and like it so far, I run it in heat pump mode but if you have a family it will need to use the heating elements. I also installed 5 Pioneer mini splits but only needed to use a 3/4 ton unit to heat my 1600 sq feet but I have R60 walls and ceilings. I live in Arizona but it was getting down into the 20s at night. Love the mini split, don't know its even on. Running it all off grid on an EG4 battery rack.
We run at 125F (instead of 120F). The heat-pump mode takes ~3hrs to reheat once the host water is turning cooler as in a shower is not desirable. The direct elements are more like 30mins compared to 3hrs. So we do a bit of planning - e.g. don't expect to take shower till 3hrs after laundry kind of thing - and it works for us.
 
I am considering higher temp with thermostatic mixing valve plus going from 50 gallon to 65 gallon. All to allow longer HP running time. I think there is also a larger diameter tank you get with the larger ones, which I think helps with standby loss via better surface area to volume ratio

There is also a new-ish 120V rheem model, the one for dedicated circuits, that has a double size compressor. I think 1000-1200w draw. I’m hesitant to buy that one sight unseen given that I haven’t talked to anyone with one yet.
 
That's why I was hoping for something with an external input (and getting one with a large tank, possibly 80 gallons) and a mixing valve.

Set the standard temp at 120f
Then when I've got excess production, run the water heater up to 140+ depending on the available sun. This will extend the hot water even further.
 
The link I posted earlier talks about a workflow to get CTA-2045 into MQTT as follows.
- buy a $20 CTA-2045 to WiFi smart app dongle
- hack up DNS to capture the server the dongle tries to reach out to. This then goes into a open source bridge someone wrote, that masquerades as the server and bridges it to MQTT

Ofc this is jankier than having a RaspPi or ESP directly talking CTA-2045, but it does give a quick way to see what the HPWH can do

The person on that thread said:

“Homeseer can change the set point and mode (hybrid/electric/vacation/efficiency) and monitor upper and lower temperature sensors and heating state (on/off).”
 
That's an option, but I think you hit the nail on the head. It feels a little janky, with too many pieces that I'll probably break down the road and not remember/realize what was involved in the set up.

Plus, I've not dealt with DNS much. I had a pi hole set up for a while, but that's pretty straightforward.
I wonder if I can set up a single DNS that redirects one address and sends everything else to cloud flare...
 
If you already have a network that puts the IoT devices in a separate subnet, vlan, other config overall, this probably isn’t a huge jump in complexity.

If you have a basic network I think it adds a new thing that can break.

There is probably an ESP thing for this by now assuming the serial is as standard as I think it is. Or maybe I’m over estimating the popularity of wanting to do this.
 
My old resistive water heater committed suicide so today installed a Rheem 50 gallon HPWH. Its installed in the garage that faces southwest and gets cooked in the Texas afternoon sun. High temp was around 85F today.

Started in heatpump-only mode and within a few hours it switched off and we had 125F water. Was actually disappointed it did not operate longer to get better cooling and dehumidification in the garage.

We habitually take showers in the evening anyway so doubt it will be much of a lifestyle change. Son reported the water was too warn so lowered to 120F. In the rare cold winter days I will switch the heating elements back on.

Next plan is to purchase the optional duct kit and create a better filter for the air inlet. The supplied screen won’t stop much dust from coating the evaporator coil.

Home Depot cost was $1700 + $65 for 5-year warranty (reliability is questionable) + $55 for delivery + tax. Curious what the electric bill savings will be. Master bedroom is above the garage so it should lower my cooling costs a smidge too.
 

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My old resistive water heater committed suicide so today installed a Rheem 50 gallon HPWH. Its installed in the garage that faces southwest and gets cooked in the Texas afternoon sun. High temp was around 85F today.

Started in heatpump-only mode and within a few hours it switched off and we had 125F water. Was actually disappointed it did not operate longer to get better cooling and dehumidification in the garage.

We habitually take showers in the evening anyway so doubt it will be much of a lifestyle change. Son reported the water was too warn so lowered to 120F. In the rare cold winter days I will switch the heating elements back on.

Next plan is to purchase the optional duct kit and create a better filter for the air inlet. The supplied screen won’t stop much dust from coating the evaporator coil.

Home Depot cost was $1700 + $65 for 5-year warranty (reliability is questionable) + $55 for delivery + tax. Curious what the electric bill savings will be. Master bedroom is above the garage so it should lower my cooling costs a smidge too.
Congrats :)

Installed my Rheem 50ga Hybrid (from Home Depot) in Jun 2019 - just finishing 4 years with no trouble. Agree that in heat pump mode it can take a couple of hours to go from 60F to 125F - not that bad but heating element (4500w) is faster for sure.

$1700!?!? Mine was $700 with 50% off - $350 total AND I got a tax credit.

I run in heat-pump only mode all the time, however, it has reverted to 4500w heating element a couple of times.
- Once when I first fired it up for just a moment
- Twice now during heat-pump error mode. I have a humidity drain pipe with a funky p-trap that needs cleaning every 2 years.
 
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