Heat Pump water Heaters

[sinoba]

Well I'm the orginal poster from nearly a year ago I posted this thread-I live about 3 hours round trip from a Home Depot out in the boonies of Humboldt county.
I was looking at the Home Depot store site at the 50 gallon reem hybrids and they had only one and it was listed as a close out -normally 1,699 and the close out was $850.I called the store and bought it over the phone that night. I looked up that model number on golden state rebates for our state and that model qualifies for a $700 off the purchase price at the store so in the am I called again and they ran my coupon number and said it was valid but I needed to be there in person to clain the discount so later that day I drove up and had them cancel my sale and start fresh and bought that Reem hybrid for $162 dollars inculding tax. So when the weather warms I will wire my lean to shed on house that contains my water heater ,I’m in the process of installing a solar hot water tank from roof water panels (80 gallon) and water mineral tank, along with a central vacuum, condensate drain, and water filter system to accommodate this new tank, and pull out the gas one. I’ll also vent the doors more and pull some 240 wire into it to see what savings can be had, and I’ll need to reach out to Rheem phone number for any further assistance with the installation. Its almost teh shortes solar day of the year and I still have battery power thru the nights and in am have about 50% of my 22.5kw bank (can only draw down to 30%) so I have some spare still to power said hot water heat pump i the dead of winter. We shall see if can work on the Northside in 40-60 degree wet winters. Not much to lose with less than 200$ inversted so far in this test.

We have two heat pumps (since we added an extension to our old farmhouse, it was more cost-effective to install a separate one), but we still use a standard electric water heater. I’ve read that heat pump water heaters are more energy-efficient, but do they heat water to the same temperature as electric ones?

 

[Zwy]

My Richmond hybrid can heat up to 140°F.

 

[Quattrohead]

but do they heat water to the same temperature as electric ones?

Yes, better still they have a digital display and buttons so you can adjust between 120 to 140 or so.
They also have regular heating elements so you can run them in standard heating mode as well as a combination of those elements for rapid recovery and then heat pump to finish it off or even heat pump only mode.

 

[Rmart30]

They also have regular heating elements so you can run them in standard heating mode as well as a combination of those elements for rapid recovery and then heat pump to finish it off or even heat pump only mode.

if just using eco mode heat pump only since its not using the elements you can replace the lower element with a DC element with thermostat and be even more efficient off a couple of panels. I wish all water heaters would come with a "spare" spot to easily install one of them.

 

[onokai]

I'm installing the heater over the next week. Taking hot air from the house and cooling it. I'm on plan B now and its in its own shed now-super tight small space but doable.The old gas water heater will be removed when its all done and my utiliuty 4x8 shed will have more space in it..The venting is the hardest part.Still have along crawl under house for wiring the 220v and need to wire into my transfer switch.Finally bought a Greenlee slug buster kit for conduit holes in panel boxes. Nice tool but rarely used.Waiting on a few parts now.

 

[onokai]

How noisy are these units? any real experience with them located in or close to home?

 

[Supervstech]

How noisy are these units? any real experience with them located in or close to home?

They sound similar to a refrigerator running.
Ive installed several in storerooms, and basements.

 

[Madcodger]

I'd respectfully argue that ours (Bradford White purchased last year) is louder than our refrigerator by a good margin, as was a Rheem we had in a previous home. Closer to a good sized oscillating room fan running on high in terms of noise level (but not set to oscillate). If you have a dedicated mechanical room out of earshot, or an unoccupied basement, it's not an issue at all (and an awesome way to supply not water). But if the building is normally very quiet (like a library), you'll definitely notice it if it's close by.

Much of this depends on how much background noise you find acceptable. We live in a very rural area, and are building a glorified she shed / guest house, which is basically a large studio-like room with the mechanical room just off of it. Because my wife will spend hours there working on art, we've decided to use an instant-on propane water heater instead of a heat pump water heater, simply because we don't want to have her (or occasional guests) forced to listen to it for the two hours or so it will be running from time to time, in a building that is otherwise silent. It's the same reason I'm looking at spending more for Victron instead of EG4, to get passive cooling of the SCCs. If you are accustomed to street noise and other sounds in a populated area, it becomes background noise. but if comparing it to silence and the sound of birds chirping, you'll notice it.

 

[Zwy]

I can hear the Richmond running in the basement if the door at the top of the stairs is open and I'm near the door. It is louder than a fridge but way less than the EG4 100A MPPT's when there is good PV coming in.

It's the heat pump fan that creates the most noise, you don't hear the compressor. Noise is comparable to the powervent propane water heater.

 

[Supervstech]

Absolutely, the fan noise is much louder than the refrigeration system. Likely in the 55DB range.

Another reason to ductbthe airflow to suitable locale.
Duct will baffle much of the noise.

 

[SkyBlue]

How noisy are these units? any real experience with them located in or close to home?

My new Rheem Proterra is much louder than the 12 year old GE Geospring HP water heater it replaced. Its probably twice as loud as my noisy Kenmore refrigerator. Its in the garage, thank goodness.

 

[onokai]

I fired up the new water heater which I installed in my old dive locker next to utility shed-really same building dived by a sheet of plywood and a separate door. I sound proofed the hose wall in this small space 32x 30. I wrapped the innver space ofer sound proffing with 1 inch foil backed foam for a R6 rating of small shed. I am ducting warmer kitchen air and exusting it to solar tank shed thru that plywood wall.. The sound level is a about like our refrigerator with a duller rumble noise which is minor when its running. The duck is also sound proofed and than insulated and is about 15 inch long. I have a recurculating hot water smart pump on the heater drain (replaced drain valve with brass nipple) to have instant hot water at all taps. Its been runing for two days now and I'm really impressed with this heater. I pulled out my 15 year old gas water heater and have lots of space in shed now. I'm insulating lines now that they are inspected for leaks . I used 3/4 copper pipe to tie it all together. The wiring was a bear as I have it tied to my backup natural gas generator and I had to use twin breakers to make room fro the double 30 amp breaker. I'll post some followup photos. So far this unit has impressed me.

 

[DVD]

My Rheem 50 has been online for a year and a half now. Yes, it has a noise level somewhat higher than a normal refrigerator, but far less than a quiet window AC. Since both intake and exhaust air are ducted, most of the noise is from the compressor itself. My EG4 8K AIO is within 8 ft of the Rheem and it produces a bit less noise than the Rheem.
With the AIO, Rheem, and portable dehumidifier running simultaneously I read 52 dB at 4ft from all three.

 

[onokai]

Wow my 12k Sol ark is super quite compared to this water heater-just a little fan noise. i have a good decibel meter I'll check that out

 

[onokai]

This small shed is next to my utility shed on the north siude of house and is the only location for an warm air intake from house (under kithen cabinets ). This is against our north side kitch wall which is 2 layers of 3/4 redwood boards offset, 1inch foil backed foam and 3.5 inchs of fiberglass dense pack insulation and 5/8th sheetrock.
I had to custom make a intake box a bit like a periscope as the air intake is below water heater body and vent is about 16 inch above my intake in a very small space for heater. That insulated and sound deadened 90 has a few inchs of flex on it as well to lessen noise. The box is a bit oversize spec wise for good air flow. I used automotive 3/4 incg sound deading self stick roll rubber/foam over the adjoining wall in shed to deaden that sound. Then over that I used 1 inch foil backed each side foam board caulked air tight on all sides and ceiling of dive locker ,this used to be my commercial helment and broco underwater torch shed which had commercial dive tools (now retired from that workand sols that stuff)
I wrapped that metal 90 intake vent with that foam deading heavy rubber then insulated it. I'm exhusting the cool air into my 80 gallon solar water tank shed 3x 8 feet.That also had my gas water heater which is now gone. . If you look at my drain you will see its complex as I'm tapping a grundfus smart pump recurculator line to the drain which supplies us with instant hot water at all taps. I had the the same on my gas water heater for a decade. The smart pump converts to dc and is very much like a heat pump compressser fan in that it can do any speed and moves very slowy most of the timeas it learns your usage times-if you go away it shuts down on auto. I cannot say enough good about this system. You just run a return hot water line from furthest hot water tap and for me that was 1/2 insulated copper. It could be pex whatever.
I christened the system on Cinco De Mayo and just finished insulation of all lines after leak checks today the 10th. The intake is about 2.5 feet from our refrigerator and just under the upper cabinets and its a toss up which makes more noise when its on.
This install was in very tight quarters. I have all valves in the small shed out of the way if it needs to come out-I will have to disassemble my drain tree and there is a 1/2 inch flex on right wall so tank can slip by. Also in shed to the left there is repetitive valve on all lines as well. I also as I do with all my (3) mini splits has a Mars surge device on side of disconnect box. It has a glowing green light and I very my suggest you have one on any heat pump as teh curcuit boards can get fried very easily . So far best price on those Mars units is supplyhouse dot com. My condesate drain is rounded to a condesate pump in next shed that serves my solar hotb water system that I have had running since 1984 and one of my mini splits. It pumps the water away from house foundation to some rhododendrons away from house so my cider tree roots which like water can access it without tearing up the foundation. (that happed already and was a pain to repair ).The job came out pretty clean. I took my time and did it right.So far its worked great.My gas heater was 15 years old and I pulled the anode rod and it was on fumes.

 

[onokai]

I like to label what going on for my wife and the next owner. (been here 53 years) Direction of flow and what system

 

[Supervstech]

I like to label what going on for my wife and the next owner. (been here 53 years) Direction of flow and what system

Very helpful for those that cant see exactly whats going on and understand it.

 

[CaliSunHarvester]

I like to label what going on for my wife and the next owner. (been here 53 years) Direction of flow and what system

For a year now, it starts to become clear to me that my labels and external documentation (a WordPress based web site) may be more for myself than the next owner. As I start to forget things.

 

[time2roll]

My 120v 65gal AO Smith has been working great for a whole week now. Works perfectly. Seemed to take 12 hours for the initial heating and yet plenty of hot water for the two of us. Cannot hear a thing inside the house and DW is very sensitive to noises. Dropped the set temp down from 120 to 115 to go a little easier on the compressor. May go lower once some additional remodeling is done late this year. No issues with the Grundfos circulation pump and bypass valves.

Next is a heat pump for the pool..... Looking at the Madimack InverElite 90,000 BTU for a 10,000 gal pool.

 

[BerndL]

Do any of these run off of external air? It doesn't make sense to use heated indoor air here most of the year, since we use the mini split in AC mode for a week or two, tops.

I should really stick a power monitor on my electric water heater circuit, see how much it uses to heat vs stay hot.

 

[time2roll]

Do any of these run off of external air? It doesn't make sense to use heated indoor air here most of the year, since we use the mini split in AC mode for a week or two, tops.

Air can be vented to the outside if preferred and there is reasonable access. Mine is mounted in a closet on an exterior wall. Air comes in through the exterior door vents and out is vented up through the roof.

There is a temperature limit that will push the system to resistance heating if too cold or even too hot.

 

[onokai]

They all run of external air (meaning air that comes to unit)-its just where you decide what air to use. I live near the cooler coast in extreme Nor-Cal and AC is not really required so the inside air is warmer than outside air most of year and they work better with warmer air. If your outside air is warmer use that air-you can duct them (8 inch) to whatever air is best suited as well you can exhaust the cooler air any where as well.

 

[BerndL]

They all run of external air (meaning air that comes to unit)-its just where you decide what air to use. I live near the cooler coast in extreme Nor-Cal and AC is not really required so the inside air is warmer than outside air most of year and they work better with warmer air. If your outside air is warmer use that air-you can duct them (8 inch) to whatever air is best suited as well you can exhaust the cooler air any where as well.

I mean it's not worth it to use them if they're using energy to cool down air you already used energy to heat.
If your mini split used 1W to move 2W of heat from outside, then your water heater uses 1W to move 2W into your water, you've burned 2W to make 3W of hot water, and used two loud and expensive machines to do it.

 

[onokai]

The idea is use the warmest air you have(you already paid to warm it) -for me I have also added a solar preheated water to feed the water heater so it does less work to heat that warmer water. The water heat pump exhausts cooler air as well. I'm not using cool mini split air to feed the hybrid water heater.

 

[chill633]

I bought one of these solar furnaces with the intent of ducting the heated air over to the intake of my heat-pump water heater. Plenty of YouTube videos on how to make your own if you don't want to buy one. That company also sells kits.