Arctic Heat Pumps: any experience or installs out there?
Hi,
I’m wondering if anyone in the GBA community has experience with Arctic heat pumps. We are looking into cutting edge options for point source cooling and are interested in what I’ll call the one heat pump to rule it all approach. We’ve been looking into Chiltrix but I recently heard about Arctic heat pumps, in the comments on another GBA Q&A I believe.
https://www.arcticheatpumps.com/specifications.html
The arctic appears to offer a few additional options over the chiltrix:
– It looks like more the plumbing is more conventional for hydronics which presumably makes it more friendly for retrofit and for mixed systems. A mixed system of fan coils and floor loop or runtal style radiators is probably a lot more flexible for a lot of residences where there are rooms without cooling load or where fan coil noise or look might not be acceptable.
– The arctic purports to operate to -13F. While both -4F and -13F are below my design temperature, I expect a unit with a -13F minimum should produce a lower temperature balance point.
– They do offer 3 outdoor unit sizes that seem very appropriate for residential settings. (yes, you can chain chiltrix units)
So my questions:
– Anyone ever seen or installed or used one of these units in the wild?
– Anyone happen to have additionally performance data for them? While there is some data on that specification page, I’d think to really determine backup heat costs, balance points, and IPLV/NPLV, I need more than the single number COP.
– The heating COP, dependent of course on those ambient temperature curves, looks pretty good at 3.61-3.71. However, I was having some trouble finding the exact comparison for mitsubishi mini splits (HSPF not really being very comparable for IPLV/NPLV). What’s your take on heating COP in the 3.6 range?
– The cooling COP, dependent on the load to COP curve I’d expect is 2.5. Am I correct to interpret that as mediocre? Looking at the old NREL study (pretty out of date now I think), I see cooling COP test results above 3.0 for our design temperatures.
Opinions? Expertise? Experience?
Thanks!
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
>"What’s your take on heating COP in the 3.6 range?"
It's not realistic number.
The COP will depend on more than just the outdoor temperature, the load (if modulating), and the output water temperature matter too (a lot.)
Take a look:
https://www.arcticheatpumps.com/images/2018/09/01/performance-curve.png
The curves for water temps of 15C and 26C are hysterically funny when put into a home-heating context. Seriously, 15C- 59F- it would be drawing heat from a 68F room, not heating it. And 26C= 79F, not warm enough to heat anything but a superinsulated cube with no windows. Those curves are just visual noise to make it look more efficient. Those temps would be for applications very different from heating a house (snow melting applications, maybe?)
A water temp of 35C might work with a radiant heat in a high-R house, 40C for a gypcrete slab in a not superinsulated house. For a fan coil anything cooler than 45C is going to induce serious wind-chill, but could be done at 40C with a very careful placement to ensure it doesn't blow on anyone with a body temp of 98.6F.
You might hit the 3.6 mark as a seasonal average with 45C water in a fan coil in the San Fransisco Bay area, but any place that's actully cold is going to really struggle to break 3.0 for a seasonal average even with a lo-temp radiant. With 35C /95F water when its -7C/+19F outside it's delivering a COP of about 3.0.
But if they left off the 15C and 26C curves, someone looking to simply keep a space above freezing or with a radiant floor would justifiably ask for it.
With outdoor reset and a continuous circulating radiant floor heating design, you very well could be circulating water in the range of 78°F. :)
Edit: I see now this post is old...oops
Keith,
I just installed an 060A for my house. I'm using it to heat a bulk storage tank (700 gallons) that my radiant draws from. The storage water is isolated, all heat transfers via heat exchanger.
Install is pretty easy. It's only hydronic + electrical. The controller is running only in water heating mode (drives the tank temperature to setpoint, tank sensor is supplied with the unit, has about 20 ft of lead(?)). The controller itself is OK, leaves a lot of room for improvement. Hopefully I'll get it set and then not touch it. There is a fair bit of information feedback you can read from it, but the manual doesn't have scaling info, and the resolution on some datapoints is lacking.
I haven't run it yet in cool enough temperatures to really say how well it works. My house needs water in the 95-105F range (lots of radiant area, decent insulation). Because the heat pump is running into an exchanger this means the outlet temp ends up at 115 if I'm heating to 100-105. On the table Dana referenced I start on the blue curve and end up on the red. I will use this mostly in the shoulder seasons here in VT so I expect my COP to range from 2.5 to 4, but probably only averaging around 3.
My next challenge is trying to collect and collate enough data to actually quantify how it's behaving. It's on my mental to do list, but doubtful to be in place before this heating season gets going.
Not sure this is in time to help you, since you posted 1/2 a year ago, but maybe it helps someone.
Austin,
I am looking into putting in a system similar to yours but with the medium sized unit. I like the rebate available in Vt, but I am a bit bothered by the lack of information about the company.
Are you still happy with the performance of your system with the 060A unit and did you find out anything about the company? Their website is not very informative and some of their copy look like fairly poor translations.
Hi Terry,
Yes, so far so good. I haven't had any time to instrument further so I don't have much in the way of scientific data. Until recently it was typically drawing ~3.1 kw when operating. I was getting 15-20 kwh of heating into the water tank in 2-3 hours. So reasonably decent COP. But I have it set to only operate between noon and 6 pm, so it's kicking on daily at noon and running for 2-5 hours, then not running again until the next noon. This is heating my 700 gallon tank up to 105 from between 75 and 85 deg, depending on how much heat load we've had. Now that it's cooling off and the run times are more often 4-5 hours I suspect I'll have to lengthen the window at some point. This will bring down the efficiency because I won't be heating in the warmest part of the day, but such is life. We'll also start to augment with the wood system soon.
I agree there isn't much info available. The guys I bought it from were OK to deal with, but not sure how far in depth they go technically. Call them up and ask questions, see what you get, can't hurt (this is the guys in Manitoba, I can dig up contact). Agree the translations aren't the greatest. And the controller continues to underwhelm, but it's doing what I need for now.
Side note, the rebate was slow to process, going slightly over the 60 day window, but it claims my check has been sent. Hope to get it this week.
Hi Austin,
Thanks for the info; I have been in contact with Dan Jung at the company (at least he is the one who responds to the web queries. He did send me a pdf of the installation and instruction manual, which is fairly helpful.
Also, thanks for the info about the rebate being slow. I will make sure I get the ducks in line at my end. The rebate really cuts a big hole into the installation cost!
Hi Autin Cate,
Im putting in a new system and am curious about your experience.
I want hydronic heating and not sure about my domestic water supply.
Did you consider a hybrid hot water tank?
Hi Austin Cate,
Im putting in a new system and am curious about your experience.
I want hydronic heating and not sure about my domestic water supply.
Did you consider a hybrid hot water tank?
Will have 4 of these systems installed this month including one on my house. Stay tuned. But impressed with them so far.
Terry. I have two systems commissioned now (60A with EcoUltra buffer tanks and low temp radiant on a pretty tight 2600 SF house). The first one has seen -5 temps and kept up with the demand without backup tank element kicking on. We have some monitoring on total daily electrical use but need to sort through it a bit when more time is available. Some comments on the HP.
-Controller is pretty basic (I actually like the Chiltrix one better)
-Having three output sizes is a huge bonus.
-HP is quiet, good looking and seems well engineered. Easy set up.
-These A2W units (Chiltrix included) are very serviceable compared to a traditional A2A mini splits. Removing the cover allows for easy to access - and if needed, replacement - of any components which is a big deal as an installer.
-Unlike the Chiltrix the pump is external and not set up for a high efficiency 120v ECM pumps which is a bummer. But did a little work-around and are using 110v Grundfos Alpha 26-99s on the 60A and will test the small Alpha on the 20A (should meet flow rate requirement). This will improve the COP a bit.
-Tech support has been good from Arctic (and is good from Chiltrix).
-Very compatible with solar thermal (you already have a glycol filled tank, available ports, an expansion tank, and pressure relief valve; our systems are designed with PV sized to offset usage of the HP and with the goal of being close to net zero).
-If I can find the time I want to do a side-by-side test of Chiltrix and Arctic heating a 40-gallon tank in similar conditions and nail down the COP.
-More to say but short on time at moment and would be glad to discuss if you send me a PM
Todd,
Thanks for your detailed information! If I knew how to do a PM here, I would, but I haven't been able to find out how.
Great to hear that technical support is good; that is one of the 'iffy' areas in my decision process.
I am hooking this up into an existing interior wood-fired boiler which I intend to use when the HP can't keep up; I mostly want to knock off some of the shoulder season and daytime load when the wood boiler isn't very efficient. The boiler has about a 100gal water jacket which will serve for thermal storage from the HP. The use of glycol is going to decrease the performance of the system, but I think it will be worth it.
Was your 'work-around' for the circulator anything more than just using one side and neutral of the 220 output for the circulator?
Thanks again, Todd!
Terry
Yes work-around for pump was one side of the 220, plus pulling a neutral from an available source.
Sounds like the Arctic HP should do the trick for you. What size HP are you going with?
I guess I don't see a way to PM either. Guess I shouldn't post my contact info here either....
Hi Todd,
From the manual, it looks as though I could just pull one of the legs of the 220 to the external pump and bring in the neutral from the HP 220 supply, but then again, I don't see a neutral connection on the input terminal block. I would just run in a neutral from that 220 line to go directly to the pump terminal block.
I am planning on the 040A; I do have a big house (lot of surface area anyhow), but I think this one will cover most of what I want.
A way to do PM or exchange contact info would be a logical enhancement for the board.
Have a good week!
Terry
I am trying to convince myself that the Arctic Heat Pump POOL-060ZA - 25 Kw - 85,000 BTU will be able to heat my hot tub in the North San Francisco Bay Area all year round. The local pool / spa installation guys do not have a high opinion of heat pumps, but I think they just do not know much about them. My hot tub is ~1350 gallons. In winter the air temperature rarely drops below 32F at night and a cold day is around 50F. I would like to maintain a temperature of 104F. Can this pump meet the requirements? How long will it have to be on each day? Are there alternatives I should be considering?
It's impossible to answer those questions without knowing how well-insulated your hot tub is.
Did you end up installing an Arctic Heat Pump for your hot tub? If so, how is it doing? Especially in cold weather?
I can speak highly of the Arctic products. Installed nearly 15 (none were for hot tubs) last year including on one my house. Their specs seem accurate and cold weather performance as advertised. I am sure if you called them they cold see if the output of the unit is sufficient to meet the demand, and of course as the as the last post referenced, insulation is key. Let me know if you have any more questions.
Todd,
On the Arctic site they discuss "precise temperature control" by modulating compressor frequency. My unit doesn't seem to do this, it's just on/off with tank temperature hysteresis. Do you have any experience with this feature? I got the list of advanced parameters in the controller, and I think I know which one to change, but there is no commentary on what to change it to.
Thanks
I'm going to bump this with a reply (since can't pm) to see how things are going almost a year later as I'm interested in the arctic hp as well.
The modulation may vary with temperature and supply/return temps and probably require comparison of the the inlet/outlet coil temps, DC motor speed, DC/AC voltage, etc etc under different temp and load conditions -- which would be a bit tedious. A call to their Tech Support could give a better answer (they have been responsive to any of my questions).
Being a total energy geek I though a could save even more energy by reducing the defrost cycle and in January (2 weeks after fiddling with advanced parameters) I was wondering why the HP seemed to be running more than usual. I discovered it was fully iced up! Humbled, I realized the hard way that the default settings are fine and not worth micro managing.
Todd,
Agreed it's hard to collect the data and process it to get to a scientific answer, I guess I was mostly hoping you might have heard what do do with the frequency setting. When I asked Dan J he didn't comment, I'll follow up.
I haven't messed with defrost, it seems to work ok. I did reduce the temp where the pump runs to prevent freeze up to the minimum since I have plenty of glycol in my system.
Thanks for the feedback. My hot tub is built in and made of concrete. I really do not know what insulation was used when it was built, but it seems to heat up Ok with my gas heater and retain heat for some time . The gas heater has finally died which is why I am am looking at the arctic heat pumps. I have spoken with Arctic and they assure me that it will work, but I wish I could talk to someone who has actually done this in my area. The local "pool experts" say they have had bad experiences with heat pumps, but their only have experience from traditional pool heater vendors like Hayward and Pentair. I am trying to contact Cedar Hot Tubs who have a relationship with Arctic to see if they have any references I can contact. Thank you Todd and Austin for your help.
It seems to me to be a BTU question. The better the insulation the lower the BTUs. The heat pump will deliver specified BTUs per hour. So if the HP can deliver enough hourly BTUs at the coldest temps to meet your anticipated hourly heat loss you should be fine. As for the contractor that has "bad experiences with heat pumps" --- I would look harder for one that is more open minded to new technologies. Or you may need to entice your local contractor to try something new by accepting a modified warranty (perhaps you buy the hardware and they install the system on an hourly basis and their warranty only cover covers their piping/wiring). These heat pumps are quite easy to service -- very modular and accessible interior components.
It should not be hard to to calculate the BTU needed. If you turn off the heat, measure the temperature decrease over a few hours and multiply by the number of pounds of water (8.34 pounds per gallon or 62.43 pounds per cubic foot) and divide by the number of hours you should have BTU per hour. Right?
You need the outside temperature too. That gives you BTU/hr per degree of temperature delta. That will answer the question, what is the coldest outside temperature where hot tub temperature can be maintained?
I'd probably start by looking at the faceplate on the existing gas heater to get an idea. If it's not in the same ballpark as the heat exchanger I'd be concerned.
Covid 19 overtook this project, but I have now ordered the Arctic Heat Pump POOL-060ZA - 25 Kw - 85,000 BTU. There is some shipping delay. I hope to have it installed by July. I will let you guys know how it works out.
I'm looking at installing an Arctic Heat Pump system here in Sitka, Alaska. I've decided on radiant to heat my 600 square foot garage slab downstairs and 1200 square foot upstairs, pex in the slab and a raupanel or similar product for the upstairs living area.
I don't want to use a gas or oil boiler. I looked into a direct electric system which looked great for the install and for ease of use, but the cost to run it with our high electric rates here was prohibitive. That's when my line of research directed me to Arctic Heat Pumps, which claim to produce the same heat for 1/3 to 1/4 the electricity, can do heating and cooling, and offer on demand hot water for the house as well. Alan and Chad at AHPs have been friendly and responsive. My next step is to supply them with my house details and have them draw up a plan to size my units and provide the necessary components for the system.
I've yet to make contact with an HVAC tech locally who can help with the install and service. Although I can do much of the work myself, I will need to have someone to sign off on my work, charge the system and help if any problems arise.
If anyone has any feedback, questions, or other information for me would be glad to hear it. I appreciate the above info from the previous posters and will update this thread as to my progress and experience with the system.
Hello zwass, I'm wondering if you installed the Arctic Heat Pump system and if so how is it working? I have been researching heat pumps to determine if they are viable for a new house we are building in Girdwood, Alaska this summer. I came across the Arctic Heat Pump system and it looks like a lot of thought has gone into designing it, just wondering how well it works. Natural gas fired furnaces are the norm here, and I'm still trying to figure out the annual cost of running a natural gas furnace/boiler versus a heat pump system. I can't seem to find much written about heat pumps in southcentral Alaska, so I don't think many exist. I'm guessing it might be more expensive to run the heat pump versus the natural gas boiler but there is also the issue of reducing carbon emissions and footprint. Any information you have would be appreciated, thanks!
Feel free to email if you have any specific questions. [email protected]. Been happy with the unit at my house and other Arctic and Chiltrix units I have installed.
Hello,
Has anyone had issues with high refrigerant pressure issues? Mine 020a has been installed for 1.5 seasons and this winter was the true test. When the temps got below 10F my HP would hit the high pressure limit. My heat exchanger and circulator pump on the supply loop is more than enough. Im thinking issues with the charge weight. Thoughts?
just to follow up. My issue was with a 15% refrigerant over charge from the factory.
I recently installed an 060A to replace a Daikin Altherma in an indoor pool heating application.
As others have mentioned, the heat pump looks well built and installation is straight forward. The only criticism I have is that the 1.5" fittings are plastic so you will want to be careful tightening them. A neat feature is the ability to externally control the heat pump with either a timer or in my case a PLC. Newer versions also connect to a wifi network which allows you to set the target water temperature and monitor the current outlet temperature.
Instructions are ok but not great. I had 3 different versions of the specifications (company website, manual and equipment plate) and they were all different! I gather that the manufacturer makes many different versions of the heat pump and specifications are subject to change, but things like water flow and current requirements impact design so you may want to wait until you receive the heat pump and check requirements before you run electrical lines or choose a pump. Unlike the Altherma there is no internal pump or backup heater.
Overall my experience has been positive. The heat pump seems to operate as designed and I estimate that the BTU and COP ratings appear to be reasonably accurate based on my experience with the Altherma. The only issue I have had thus far is that the lower few inches of the heat pump ices up in colder weather and the defrost cycle isn't sufficient to melt it. There must be water collecting but I haven't had a chance to investigate further yet and it doesn't stay cold long enough here for it to build up to any degree.
I found tech support in Manitoba to be good and they were able to answer questions I had about dip switch and operating environments that the manual didn't clearly outline.