Seeking a Quiet Heat-Pump Water Heater
joelgoyette
| Posted in Mechanicals on
Has anyone gone down the rabbit hole already to identify heat pump water heaters that don’t have compressor noise, pitch or vibration issues?
I want to go with a HPWH for this build, but will have bedrooms relatively close to the mechanicals, so want to avoid anything excessively noisy.
Thanks for sharing any findings or feedback. I’ve read almost every post on GBA about this, but it seems to be model year dependent.
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There have been some reports on GBA that Rheem has resolved the noise issue with the release of its 2022 HPWH. I'm looking for a 50 gallon unit and keeping my fingers crossed. I had a first-gen unit, and it was fairly quiet.
Is the 2022 unit a distinct unit from the Gen 5 that had all the problems? Or is it the same unit, but just says "2022" on the sticker with the manufacturing date?
Thanks Steve. That's great to hear. Will keep an eye on reviews and comments to see if complaints diminish. I also have a unit from a few years ago that is fairly quiet, so hoping to find a unit that can match that experience.
Supposedly whatever was causing the loudness issue has been addressed, but I don't think Rheem is treating these changes as a model update.
@Steve Knapp CZ 3A Georgia: do you have a link to the evidence that the problem with the Rheem has been fixed?
I've replaced our Rheem unit twice, and read a lot of the online discussion, and all I've seen is that it might have dropped from 65 dB to high fifties -- still much louder than 49 dB. 59 dB is twice as loud as 49 dB, and I don't want that inside the house.
In my city, if you have an outdoor AC condenser that produces 50 dB at your property line, your neighbor can complain and you have to add soundproofing to get it under 50 dB. I wouldn't install a Rheem without some stronger assurances.
The first time I replaced it, Rheem covered the full cost. The second time, they did not and I was out of pocket for part of the expense. I'm running it in electric mode until I'm really sure they've fixed it...
One option would be to go for a split unit like the SanCO (formerly known as Sanden) units. These just have a stainless tank with no moving parts on the interior and a compressor/condenser on the exterior. They also don't dump cold air in the space nor do they need to be vented. They are more expensive, but if noise is a big issue it may be worth considering. They also are extremely efficient, use CO2 as a refrigerant and hold water hotter so they have additional benefits that could offset the cost.
@Josh Salinger: A few questions about these:
1. What is support for them like and is there a dealer network? Are they installed by plumbers or HVAC professionals?
2. What is the approximate cost of one of these?
Thanks
Over $5K US plus installation.
I *really* want to like the SanCO2 unit, but living in CZ5 I'm ruling one out due to the fact the heat exchange process sends the water to be heated to the exterior unit (compressor). I don't want to rely on heat tape around the water piping running to/from the exterior unit to keep things from freezing. It seems having a separate closed loop running between the inside and outside units, which could still be water but with an anti-freeze additive, would have been a much better approach.
@Joel: I'm one of the unhappy owners of the Rheem Gen 5. Don't buy it :-)
I've been looking at the AO Smith, which is claimed in some places to produce a much more acceptable 51 dB. If you read the reviews on sites like Lowe's, you'll see that some people are happy, and others complain of unspecified noise levels. There's a video on YouTube of one person who installed in the garage and claims it's about 75 dB.
Rheem sells a vibration isolation kit. Basically just rubber feet that can handle the weight of a full water heater. I'm sure that couldn't hurt for any brand, and you could buy online for more like $20. Flex duct has insulation and can catch some of the noise coming from the fans.
I really want someone to share noise measurements on a fixed Rheem, or on a current model AO Smith or other brand.