Air to water heat pump?

[Farmer29]

I am running a portage &main 160 gallon wood boiler to heat my 50X72 Shop with infloor heat and would like to know if a air to water heat pump
would work to cut down the work load for me without being to expensive to operate . The boiler works great but is getting to the end of its lifespan .
Any suggestions would be appreciated

 

[pcmeiners]

Air to water heat pumps, are very expensive, most of the unit are used in Europe and the far east, they produce higher temperature water then a standard heat pump would. They should not be as expensive but low supply and low demand make it so. Operating cost would be low but initial cost and the cost of possible repairs make it impractical at this time.

 

[Jackfre]

Living in New England when I represented Fujitsu I pushed them to being in the A-W units. They have them but 20 yrs later they are still not in the NA market. Daikin had theirs out a but pulled it off the US market 5-6 yrs ago after a very limited run. I think PC is correct. Europe is hydronic heaven and geo-politics are driving HP’s to that world.

 

[fitter30]

AWHP air to water heat pump. They only put out 120° f water and use high efficiency heat emitters. Just Google awhp for tons of info. There are a lot of different companies making components and equipment. High efficient fin tube a more than twice the fins that are enhanced per foot and have a supply and return piping.

 

[jmdirk]

Following out of curiosity.

The marketing seems...optimistic.

Some claim to work down to like -15 or so. COP drops at those temps, but in theory should still be beneficial at that point. I've only seen hydronic designs there where they use a buffer tank. So if that space is a concern there's that to consider.

 

[Highbeam]

I'm waiting for the awhp to come to america but we don't have them yet so keep feeding that wood boiler.

 

[pcmeiners]

"They only put out 120° f water and use high efficiency heat emitters."
A regular heat pump does not produce a high temperature heat exchange, the heat pumps used for heat pump hot water are different, using different refrigeration gas, and very large BTU output components, producing high water temperatures needed .

 

[Phuckin' Jim]

Air-to-Water Heat Pumps for Home Comfort | Arctic Heat Pumps

Get specialized air-to-water heat pumps built for extreme cold in North America. Reduce energy bills, lower emissions, and ensure your entire home's comfort.

www.arcticheatpumps.com

No affiliation, just thought it was interesting.

 

[jlv03]

I’ve been patiently waiting for the tech to take off, but it’s just not there yet. CO2 seems to be well suited as well as the refrigerant.

 

[Farmer29]

Following out of curiosity.

The marketing seems...optimistic.

Some claim to work down to like -15 or so. COP drops at those temps, but in theory should still be beneficial at that point. I've only seen hydronic designs there where they use a buffer tank. So if that space is a concern there's that to consider.

 

[86turbodsl]

AWHP is good tech, but the us market isn't really ready for it yet. The emitters need to be low temp, and most of the hydronic in the US is high temp emitters suitable for boilers. The home has to be designed from the get go to be a low temp emitter house. GSHP / hydronic is where i ended up, and i had a hard time finding anyone to do the job, ended up redesigning it myself and finally got the system where i wanted it. AWHP would have been much cheaper.

 

[jmdirk]

AWHP is good tech, but the us market isn't really ready for it yet. The emitters need to be low temp, and most of the hydronic in the US is high temp emitters suitable for boilers. The home has to be designed from the get go to be a low temp emitter house. GSHP / hydronic is where i ended up, and i had a hard time finding anyone to do the job, ended up redesigning it myself and finally got the system where i wanted it. AWHP would have been much cheaper.

Would the AWHP not be ideal though for a in floor radiant heat setup like the OP has? My understanding it that most in floor radiant system don't need or require super hot input fluid temps.

I'm very curious about the AWHP for my application as well. The electric boiler is nice and works fine, but it's not cheap to run. If a AWHP can run at 1/2 or 1/3 of the cost for most days and keep the electric boiler to supplement heating on only the coldest days it could be a decent investment. Also seems like the buffer tank is a requirement for the AWHP to prevent short cycling and also provides some additional thermal storage for those super cold days as well.

 

[pcmeiners]

"My understanding it that most in floor radiant system don't need or require super hot input fluid temps."

True but with lower temperature water you need better heat transfer in the slab, and you still need a high BTU output mini split.
What we need is the perfect refrigerant gas.

 

[86turbodsl]

Would the AWHP not be ideal though for a in floor radiant heat setup like the OP has? My understanding it that most in floor radiant system don't need or require super hot input fluid temps.

I'm very curious about the AWHP for my application as well. The electric boiler is nice and works fine, but it's not cheap to run. If a AWHP can run at 1/2 or 1/3 of the cost for most days and keep the electric boiler to supplement heating on only the coldest days it could be a decent investment. Also seems like the buffer tank is a requirement for the AWHP to prevent short cycling and also provides some additional thermal storage for those super cold days as well.

Correct, ASWHP is a good fit for slab hydronic heat, assuming it's about 20 Btu/ft requirement.

 

[86turbodsl]

Would the AWHP not be ideal though for a in floor radiant heat setup like the OP has? My understanding it that most in floor radiant system don't need or require super hot input fluid temps.

I'm very curious about the AWHP for my application as well. The electric boiler is nice and works fine, but it's not cheap to run. If a AWHP can run at 1/2 or 1/3 of the cost for most days and keep the electric boiler to supplement heating on only the coldest days it could be a decent investment. Also seems like the buffer tank is a requirement for the AWHP to prevent short cycling and also provides some additional thermal storage for those super cold days as well.

You don't need a buffer tank on a slab. The slab is an enormous buffer tank.

 

[Farmer29]

You don't need a buffer tank on a slab. The slab is an enormous buffer tank.

Thanks for the input. I am going to inquire further into the AWHP as the temp in the radiant floor would only be about 110 degrees
with the tempering valve so I think that water temp shouldn’t be an issue

 

[86turbodsl]

I concur. Low temp emitters like slabs are great for heat pumps.

 

[Jackfre]

Be careful what you go with here. You are absolutely in the “early adopter” segment of the market and there is some risk in that. Companies tend to come and go at this stage and they tend to leave a bunch of orphans out there. Find the unit, but make sure you ask what the primary service parts are and stock a set of them on your shelf. Also skip the sales folks and make sure that you speak with the Tech Service dept to make sure there is competent help there. It is an ideal application…if you can find the right unit. Please keep us posted on your progress.

 

[fitter30]

I'm waiting for the awhp to come to america but we don't have them yet so keep feeding that wood boiler.

What are you writing about awhp. Carrier, mitsubishi, chiltrix, lg therma v and space pac just to name a few. Chiltrix has been around for at least ten years.

 

[Highbeam]

What are you writing about awhp. Carrier, mitsubishi, chiltrix, lg therma v and space pac just to name a few. Chiltrix has been around for at least ten years.

As jackfre wrote (admittedly paraphrased), there is no established awhp on the market. Nothing we can use with any sort of confidence. I'm anxiously waiting.

 

[86turbodsl]

I'm building an air/water heat pump (or portions of one) for the shop this summer hopefully. There will be some valving to allow me to dump heat into the floor slab heating system. Or into the air handler for a/c.

 

[SolarRob]

I am considering this one for my radiant project, https://www.mbtek.com/collections/air-to-water/products/apollo-3-5-ton#
I am researching the company, it seems like they are transitioning into this market from wood boilers. I also understand most of the available systems, Arctic, SpacePak, and the one I linked, are rebadged versions coming from a single manufacturer out of China.

 

[pcmeiners]

Installation/specs/performance of Mbtek Apollo....

APOLLO Heat Pump Air-Water - Installation & Maintenance Manual.pdf

drive.google.com

 

[haveissues]

I am considering this one for my radiant project, https://www.mbtek.com/collections/air-to-water/products/apollo-3-5-ton#
I am researching the company, it seems like they are transitioning into this market from wood boilers. I also understand most of the available systems, Arctic, SpacePak, and the one I linked, are rebadged versions coming from a single manufacturer out of China.

The issue I see is the rated heating capacity is at 68f. At 10f its almost half the rated Capacity. The spacepak extreme has much better performance but is also much more expensive.

 

[pcmeiners]

Be careful believing stated specs from mini split manufacturers. At this time all the competitors are not adhering to standard measurement practices; sort of reminds me of the compressor industry.
Now the industry is suppose to be using EER2,SEER2 and HSPF2 not the older standard EER, SEER, HSPF, by law..so much for any agency insuring this. The Federal government is very lax in compliance, they are afraid of hampering commerce.

Much of the industry relies on this......

“If you can't dazzle them with brilliance, baffle them with ********.”

 

[wbclassics]

Efficiency Vermont has a list of AWHPs that are suitable for managing the load of an entire building in northern cold climates. They use a singular rating for COP at an operating condition of outside air temp at 5F and a water (supply) line temperature of 110F.

https://www.efficiencyvermont.com/Media/Default/docs/rebates/qpls/efficiency-vermont-awhp-qpl.pdf

A significant number of those listed, in particular the ones from SpacePak, are coming from Phnix-E in China:

Heat Pump Manufacturer | Air Source Heat Pump | House Heating Heat Pump | Swimming Pool Heat Pump | PHNIX

PHNIX is a professional heat pump manufacturer. We committed to research & development, and manufacture of air to water heat pump for house heating, cooling and domestic hot water, all-in-one heat pump water heater, commercial heat pump water heating solution and Full Inverter Swimming Pool Heat...

www.phnix-e.com

MBTek's wood boilers come from a manufacturer in Belarus, but it is likely their Apollo brand AWHPs are Chinese sourced. They have the best pricing, MBTek as a company seems to just be an importer with no real premises or assets in the USA. One of their addresses is just a 3rd party logisitics warehouse in Philadelphia.

I think overall we'll see more AWHPs from Europe start to come to the market, but at a significant price premium to the Chinese units, but also higher operating efficiencies. Stiebel Eltron's units on the Efficiency Vermont's list have been newly added in the past few months.

 

[rcgustafson]

The AWHP scene in North America is evolving. Two good looking systems have recently come into the market. Enertech introduced the Advantage and it's manufactured in the USA. However, they have had a delay in certification in California and I'm not sure if they are past that yet. Taco Systems has introduced the System M. It's now in production. Both of these systems look like advances over previous systems and both come from well established companies. The trick is finding an installer. You may have to convince your installer to get qualified with these systems and there may not be a big enough demand yet, so you will be sold on a SpacePak or Chiltrix. I'm pushing two installers to take on Enertech or Taco. Since Taco has a big footprint in the HVAC and pump world, it may be the easier route.

 

[durk_2007]

The high end "warm board" hydronic company uses space pac AWHP for their systems. that gives me a little more confidence if they are willing to put their name to a partnership

 

[pcmeiners]

M system......$38,000.00

Taco SystemM-1

Order the SystemM-1 at NorthStock.com. Low Prices and free shipping on all Taco Comfort Solutions hydronic pumps, parts and accessories!

northstock.com

 

[dcg9381]

Aren't some commercial HVAC system air-to-water? I've never seen one in residential.

 

[mariotheplumber007]

AWHP air to water heat pump. They only put out 120° f water and use high efficiency heat emitters. Just Google awhp for tons of info. There are a lot of different companies making components and equipment. High efficient fin tube a more than twice the fins that are enhanced per foot and have a supply and return piping.

Wrong
They can produce upto 149°f

 

[mariotheplumber007]

I'm waiting for the awhp to come to america but we don't have them yet so keep feeding that wood boiler.

Check out MBtek.com
Hydrosolar.com
STIEBELELTRON.COM

 

[mariotheplumber007]

The AWHP scene in North America is evolving. Two good looking systems have recently come into the market. Enertech introduced the Advantage and it's manufactured in the USA. However, they have had a delay in certification in California and I'm not sure if they are past that yet. Taco Systems has introduced the System M. It's now in production. Both of these systems look like advances over previous systems and both come from well established companies. The trick is finding an installer. You may have to convince your installer to get qualified with these systems and there may not be a big enough demand yet, so you will be sold on a SpacePak or Chiltrix. I'm pushing two installers to take on Enertech or Taco. Since Taco has a big footprint in the HVAC and pump world, it may be the easier route.

Personally I think Enertech and Taco system M is a bit overpriced. I would definitely go for Stiebel Eltron for $13000 or MBtek $10000 FULL HYDRONIC PACKAGE.

 

[chinboys]

Not to hijack this thread but why air to water when greater efficiencies and technology exists for geothermal heat pump systems exist....Water Furnace for example?

 

[LopezBart]

We have an air-water heat pump installed in 2021 - manufacturer is Gree. Variable speed inverter drive; temps are kept low as befits a hydronic floor heat system in a very well insulated house. Since we don't need AC, the unit also provides preheat for our hot water.
Geothermal systems make sense when the ambient temperatures get very low; in some parts of the US, that doesn't happen, so the expense of a geothermal system isn't warranted.

 

[Firebrick43]

Not to hijack this thread but why air to water when greater efficiencies and technology exists for geothermal heat pump systems exist....Water Furnace for example?

Equipment and the loop cost is so high is the main reason. 30k is not out of th question

 

[fitter30]

Wrong
They can produce upto 149°f

Is that why there heat emitters are design for 110°- 120° water. Arctic heatpump keeps temp below 131° for efficiency. Chiltrex does the same as their max temp is also 131°. SpacePac design 120°

 

[fitter30]

Aren't some commercial HVAC system air-to-water? I've never seen one in residential.

For loft,dorms and apartment buildings use a closed loop evaporative cooling tower, boiler and 1.5 - 2 ton water cooled heat pumps per apartment. Loop in winter 68° and summer loop might get to 88° when outside temp 100°. Spring and fall boiler and tower don't run much some hp's are cooling others heating. This old technology.
What is going now is VRF by at least 10 manufacturers.

Advantages of VRF | Carrier - Building Solutions

Advantages of VRF

www.carrier.com

 

[theoldwizard1]

The AWHP scene in North America is evolving.

Not sure how I missed this thread last year !

Some of the well know mini-split system suppliers (Mitsubishi for one) have been selling these systems outside of the US for years !

 

[mariotheplumber007]

Is that why there heat emitters are design for 110°- 120° water. Arctic heatpump keeps temp below 131° for efficiency. Chiltrex does the same as their max temp is also 131°. SpacePac

If you talking about max efficiency from ATWH then you shoud size your emitters bellow 100 F supply. You could reach 400 % That is why radiant slab is the way to go or combination of radiant wall and floor.

Is that why there heat emitters are design for 110°- 120° water. Arctic heatpump keeps temp below 131° for efficiency. Chiltrex does the same as their max temp is also 131°. SpacePac design 120°