Arctic Heat Pumps Air to Water Heat Pumps for Cold Weather!!

Hot_water_fan

That’s great! Maybe air to water can hit 5%? 10%?

John Ruhnke

5% or 10% of what? It can do 100% of the entire load for the house. It can hook up to Radiant Heating and Cooling, Radiators, Baseboard, Air Handler units heating and cooling both, Fan Coil Units heating and cooling both and DHW. It can do everything a Air to Air Heat Pump, can do and a lot more!! If properly installed and designed it is a lot more energy efficient than any forced air system. We can do High Water Temperature Systems without adding electric resistance.

Hot_water_fan

5%-10% of US houses. So about 100% of the hydronic market.

John Ruhnke

On the North East Coast hydronics is 50% of the market. A lot of opportunity for Air to Water Heat Pumps. There is a big void. You have a huge amount of Hps that can fit the air side of the market but a very small amount of HPs that can fit the hydronics market. I get emails and calls every single day. I need installers.

Jamie Hall

Very nice. Very optimistic. Now if you can make one which will retrofit a steam heated house or building without having to start over from scratch, you might just have something.

DCContrarian

https://forum.heatinghelp.com/discussion/comment/1811719#Comment_1811719

"You can't just take a few small clips for COP off of marketing material from a website and do a COP comparison. You have to ask for the engineering specs and take your data from that. "

I did a comparison of five air-to-water heat pumps. Arctic was the only one that didn't have data readily available on their website.

going_commando

NEEP's data is awesome. I use it all the time for specing mini splits, because their data isn't pie in the sky numbers like the manufacturers say. I used it for sizing my heat pump system, which is cheaper to operate than fossil fuels down to about 28 degrees, and is too small for the load at 26 degrees. Below that temp my oil boiler (well, once it's fully installed, which I'm working on).

It would be awesome to see their research data pointed at hydronic heat pumps. Trying to find info on those here in the states is near impossible it seems. I watch a few YouTube channels based on the UK, and they slam those things in everywhere with varying degrees of success. I am a bit doubtful as to their performance in high temp applications (fin tube in old houses), but I would be happy to be proven wrong. In new, tight, houses with radiant or panel radiators I'm sure they work very well, at least until the temperatures plummet.

I think a missing link with heat pump hydronics would be a dual fuel system with an integrated gas boiler. Let the heat pump do the modulating, and then when it needs help when the outdoor temp drops, the boiler kicks on and makes easy, simple hot water instead of using electric resistive elements. In the Northeast that would make it far cheaper to operate, and also allow for operating the unit on generator or battery backup with substantially longer run times when the heat is needed most and your local grid is down.

Here the COP equivalent of oil is somewhere around 2.7 and propane is 2.2ish. (based on energy costs and breaking down to $/mbtu). I haven't looked into hydronic heat pumps much, but I know with air source systems most fall on their face efficiency wise below 20 degrees, and end up barely cheaper to operate than electric resistive heat and more expensive than propane, oil, and natural gas.

DCContrarian

@going_commando, check out the discussion of the US Boiler dual fuel heat pump in this thread:

https://forum.heatinghelp.com/discussion/197713/trouble-getting-an-air-to-water-heat-pump-for-radiant-retrofit-in-virginia

John Ruhnke

The European standards rate the top of the line Air to Water Heat Pumps in the A+++ category. The three features needed to get ATWHPs in the top A+++ category is EVI (Enhanced Vapor Injection) Mitsubishi has Hyper Heat which accomplishes the same in a different way. DC Inverter Compressor and DC Fan variable speed fan. The only other technology rated that high is geothermal. Air to Water Heat Pumps have gained a lot in the last 15 years jumping from the B and A categories up to A+++. Geothermal has made small gains but not nearly as big as the gains of ATWHPs. In order to be in that category you need to have a average seasonal efficiency over 300%!! The standard lists A+++ as over 120% and uses a conversion factor of 2.5 for electricity. They are penalizing electricity for losing energy at the power station and over the transmission lines. Electrical resistance in America is rated at 100% while according to the Euro rating system it is 40% efficient. So based on that 120 times 2.5 = 300 or Above 300% efficient.

With huge gains in efficiency for ATWHPs combined with only minor improvements in geothermal the efficiencies of the two are now so close that it does not make any sense to drill or dig your yard up.

Jamie Hall

Average seasonal efficiency is all very well. If you consider the location. Maybe it isn't quite so good in Caithness or Orkney? Or the hills of New England?

I would observe that the enthusiasm and over sell for heat pumps has been a large part of bringing down the government of Germany, and looks fair to do the same in the UK. I agree, this is politics, but folks — if the people on the ground find out it doesn't work…

Hot_water_fan

Jamie, is anyone voting based on heating options? I think that’s an extraordinary leap. I’d stop using that claim and stick to heating.

Hot_water_fan

With huge gains in efficiency for ATWHPs combined with only minor improvements in geothermal the efficiencies of the two are now so close that it does not make any sense to drill or dig your yard up.

this I can agree with! Air source, of both varieties, have made the ground source case much harder

ethicalpaul

Caithness and Orkney each have a population of 25,000. That is statistically zero compared to Europe or even the UK as a whole, not really useful when discussing heating options for general population IMO

DCContrarian

https://forum.heatinghelp.com/discussion/comment/1811694#Comment_1811694

My understanding is the manufacturer gets to pick the configuration that gets tested.

If I were doing marketing for Arctic — and this is ultimately a marketing question — I'd try to get my units listed on NEEP. If it turns out that NEEP won't test air to water, then I'd duplicate the NEEP testing protocol and post the results on my website.

Which raises the question, what configuration would I want tested? While NEEP collects a lot of data, there are only two performance points that are searchable, max output at 5F and max output at 47F, so I'd want to focus on those two points.

One approach would be to set the water temp for 113F/45C . Looking at the numbers on the Arctic website (www.arcticheatpumps.com/specifications.html) and interpolating between them I'm going to guess that the 035ZA can produce about 21K BTU/hr at a COP of about 2 at 5F. Looking at the fan coil units, the PFP-080 is rated for 11,800 BTU/hr at 113F so two of them should be able to distribute all the heat the heat pump can produce.

Arctic doesn't publish numbers for other temperatures, but I'm going to make an educated guess that if you drop the water temperature to 95F/35C, at 5F outdoor you're going to get a COP in the ballpark of 2.6 and an output in the ballpark of 24,000 BTU/hr. Those are much better looking numbers, putting on my marketing hat those are the ones I want to publish! But the fan coil units aren't going to be big enough with water that cool, figure with water only 25F above room temperature instead of 43F above room temperature their output is going to be 25/43 or 58%. You're going to need 41,400 BTU of nominal fan coil capacity to distribute that heat, or three of the bigger PFP-100, rated at 14,300.

OK, so what's the rating at 47F going to look like? If you have the outdoor reset you may as well use it. In the real world if you were running water at 95F at 5F outside, you'd be running around 85F when it's 47F outside. With water temperature of 85F and 47F, the Arctic is going to hit it out of the park in terms of COP and capacity. Probably a COP over 4. I'm not going to guess at capacity because it isn't going to matter, because for the purposes of the test you're going to be limited by what the fan coil units can produce. And with 85F water, it's not much, about 60% of what you get with 95F water, or about 14,400 BTU/hr.

So it will be interesting test results, it'll be the only heat pump in the database where the output at 47F is lower than at 5F. In the real world that won't matter, when sizing heat pumps the only capacity number you care about is at your design temperature.

John Ruhnke

Hi DCC,

I sent you a message with a bunch of pdf's, A few COP charts and temperature charts for our fan coils. If you are going to crunch numbers you might as well have the best info.

Let me know if it is helpful or if you need anything else.

Jamie Hall

Can we kindly stop the advertising and get on with work?

ethicalpaul

I don't consider it advertising. We hear 1,000 times in this forum how heat pumps don't work, so I'm happy to be able to hear that they do in fact, sometimes, work

John Ruhnke

That Toon town post wasn't from me. I have no idea who that was.

HeatingHelp.com

We've removed that post because it was a thinly veiled sales pitch and we suspect it was spam. A friendly reminder to all to keep the discussions here educational and follow site rules about not posting unsolicited promotions. Thank you.

Jamie Hall

The key word, @ethicalpaul , is "sometimes". And it would be most helpful to have a complete description of the circumstances under which they do work.

I am rather enthusiastic about them myself — in fact, there is one providing partial heat and air conditioning in part of the building which Cedric powers. In the right application, heat pumps — like almost anything else — are a very good choice.

But not everywhere and every time. Much more information is needed for the folks making the design decisions to ensure that they are actually making the best choice for the specific application. Can a specific unit work in a specific structure in Saskatoon? I have no reason to doubt the honesty of the statement. Is it the best choice for that application? Since the only information given is geographic location, I have no way of knowing. Were other approaches considered? How did they stack up? No information.

My point here is that an enthusiastic endorsement is not an engineering analysis, but advertising.

ethicalpaul

Absolutely. And I hope to see the engineering analysis next time someone says they don't work in a given location.

John Ruhnke

Jamie,

Stating Air to Water Heat Pumps don't work is like stating boilers don't work. With millions of Air to Water Heat Pumps installed all over the world for a few decades now lets just agree that they do actually work.

I am a very good applications engineer. If you have questions on how to apply a Air to Water Heat Pump to a project just let me know. You can make the case that in a wrong application a ATWHP won't work but you can also say that about a boiler or anything else. Proper design of a system is extremely important to success.

Jamie Hall

Thank you for that, @John Ruhnke . Sort of the mirror image of my point, and appreciated. Allow me, however, to state that your case for whatever technology you are working with will always be better if it includes an analysis of the exact problem, the exact objectives, and all other technologies considered and rejected and why they were rejected while the particular one chosen was, in fact, chosen for that specific application.

With regard to your first paragraph — I have never said and never would say that heat pumps don't work. They do. In the right application they are really very good. And I am sure there are millions of them out there. Are they correct for every application? No, they are not. Sometmes that may be because with the present state of the art they simply won't work. Sometimes it is because there are better solutions to the problem.

And a word, if not of wisdom then perhaps experience: it is very easy, in almost any field, for a person selling or applying a product or doctrine to become sufficiently "sold" themselves to find it difficult to see that there may be other approaches which should be considered.

John Ruhnke

@Jamie Hall,

I always recommend a customer go with a traditional air to air heat pump if they are doing hot air only. Can we make things work and supply energy to a AHU (Air Handler Unit)? Yes of course we can but it breaks an engineering rule called KISS!!! (Keep It Simple Stupid) In order to make it work I have to add a buffer tank and other related components. It is a over complicated design. So I recommend a simpler design and send them elsewhere because we don't sell those type of systems.

Now if they tell me they want to do radiant heating and fan coils on the first floor and forced air to the second floor, than I gladly recommend using our air handler unit with a low temperature coil. The customer will already have a ATWHP feeding a buffer tank to do heating and cooling to the radiant and fan coils. To follow KISS we eliminate adding a second air to air hp to feed the second floor AHU. We can simply run a couple of pipes from our buffer tank to the 2nd floor AHU. Its simpler.

John

lkstdl

https://forum.heatinghelp.com/discussion/comment/1812057#Comment_1812057

John, could you post those here for everybody to see?

Thank you.

-Luke

John Ruhnke

All PHNIX Fan Coils.pdf

ARCTIC-030ZA(BEH2) performance data TUV-F.pdf

ARCTIC-035ZA(BE) performance data TUV-C degree F.pdf

ARCTIC-050ZA(BE) performance data TUV-C Degree F.pdf

ARCTIC-060ZA(BE) performance data TUV-F.pdf

EVI Cooling performance.xls

TAG

Definitely a market for these air to water units. In areas w/o natural gas they are the ticket. Going to win operating cost against a propane or oil boiler. Install should be straight forward .. equipment cost being unknown to me.

My last couple of projects have been full floor radiant w/ propane boilers. Even with nice size projects … better building/ insulation allows for many of them to work with 60k of heat. Even my church project at 4kSF in PA works using the smallest Viessmann boiler (under 60k BTU net). It would have been great to place one of these air to water units outside vs all that is needed for a boiler hook up … even better when going in an all electric area where the only real solution Is partial underfloor electric. I'm going to be doing one in SC next year.

In PA you need proper AC .. so I had to use a combination of ducts and mini splits in that odd project. The ability to make cold water is an interesting addition and allows for some unusual possibilities.

I have had nothing but problems with my multi head mini splits … love the singles. I do wish we had more mini split model choices. The new slim Mitsubishi ceiling unit is an improvement … why they don't make a flush or semi recessed wall unit is a question. But — with air to water we could be sending hot and cold water around and end the refrigeration problem completely.