EDIT: Moved to new thread
How about these. Didn’t read it yet.
How about these. Didn’t read it yet.
Air to water heat pump
- Thread starter EbS-P
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Didn’t see much about solar but if one could get hot water off the condenser loop that would be a big bonus in the summer. But not sure how it’s better than a HPHW.
Intriguing. It appears that this may be possible, though perhaps more viable in areas that do not experience extremely cold winter temps. The ease of installation is intriguing. There are no refrigerant line connects, just hot/cold water connections and power.
SpaceBus
Minister of Fire
Basically we’re taking about an air to water single compressor whole house system. Some devices might work better as air to air using refrigerant. I think the product is out there.
The solar tie-in potential for off-grid it there with a large enough system due to the fairly low power consumption of the system.
For domestic HW heating this is recommended.
For domestic HW heating this is recommended.
How does it work with water heating?
We don't specifically offer our chillers as water heaters however they can do a great job of heating water. In this case, the chiller connects to a "heat exchanger tank" - this is also called a "solar" or "indirect" tank. It is a hot water tank with a heat exchanger coil inside. You will also use an electronic valve ordered from Chiltrix called a DN25-DHW valve. The chiller monitors the tank temperature using an included sensor. The chiller can temporarily switch from its normal cooling or heating function for a brief interval, to quickly heat the water tank whenever the tank needs heat. This is very advantageous, as water heated by the chiller can use up to 70% less energy than a standard electric water heater would use for the same amount of water heating.
Even if this type of system isn’t designed to run from direct dc you are just an inverter away from utilizing it. Grid tie it if you wish. Automatic disconnects that shut the whole PV system off have workarounds soon if not already. The thermal storage potential must be much cheaper per unit energy than current batteries but I’m just guessing.
How does the chiller heat pump work with solar?
There are two ways that the Chiltrix chiller can work with solar, you can use either or both of these methods. The chiller can be integrated into a solar thermal/hydronic heating or solar water heating system and provide low cost heat at times when the sun is not available or when the load exceeds what the solar system can provide. Secondly, the Chiltrix chillers are ideal for powering with off-grid or grid tied PV solar panels. It's ideal because it uses much less power to operate than other similar sized air conditioners or heat pumps, and it has a "slow start" function that eliminates the initial in-rush surge of current. The unit starts at only <2 amps and slowly builds up, protecting batteries and inverters from sudden high amp surge loads. The unit requires AC power which can be supplied by an inverter. See example solar chiller designs.
SpaceBus
Minister of Fire
My guess is that once you really get into pricing it a mini split and a HPHWH is probably cheaper right now. Adding what ever solar capacity you want/can afford. I’m if you have forced hot water heat it makes sense.
I also looked into building my own solar hot water collectors. This was the best guide I could find.
A Simple DIY Solar Space and Water Heating System
Detailed description of a homemade solar space heating and water heating system that is very simple to build.
www.builditsolar.com
John Seigenthaler ,the hydronics guru is the big advocate of air to water heat pumps for both heating and cooling. The problem to date is not many mainline companies are offering them and the ones that do are not name brands. As mentioned, they are limited on cold outdoor temps. They are far better at putting out a lot of warm rather than a small amount of hot water so for heating purpose they are best matched with low temp radiant heating and low temp emitters. Not very good for standard hydronic heating like Slant fin.
The big plus is no need for a tech to mess with refrigerant. The refrigerant is all outside in the outside unit. The only thing that goes through the wall is water or gylcol and power. That to me is real big plus.
They also can be used for cooling but that requires a fan coil unit with drain pan with a pipe to drain. There are fan coil units that look and work like mini split indoor units
I have taken an online seminar with one large US company but they are trying to sell a complete system including indoor equipment and shooting for to 3 to 10 ton range.
The big plus is no need for a tech to mess with refrigerant. The refrigerant is all outside in the outside unit. The only thing that goes through the wall is water or gylcol and power. That to me is real big plus.
They also can be used for cooling but that requires a fan coil unit with drain pan with a pipe to drain. There are fan coil units that look and work like mini split indoor units
I have taken an online seminar with one large US company but they are trying to sell a complete system including indoor equipment and shooting for to 3 to 10 ton range.
Its business decision. Minisplits are sold as a "quick fix" and sold through predominantly through firms that sell AC. Its pretty simple, someone is hot, they call a dealer and the dealer rolls a truck, spends a half a day to install it and the homeowner/business is cool. The only real potential delay is a licensed electrician needs to run a 240 Volt outlet. Cold climate minisplits substantially increased the market for the manufactures but they are essentially just a slight upgrade to an existing outdoor unit design.
Air to water heat exchangers are a different proposition. They are not plug and play for the vast number of homes or businesses. As I mentioned they are very good at making lots of warm water but not so good at hot water. Most homes with hot water heating have Slant Fin type baseboards and designed for 140-to-180-degree hot water, run 120 F water through those baseboards and there just is not enough heat. That means a very expensive upgrade to low temp emitters or installation of lot more baseboard. Few folks have fan coil cooling units with condensate pans and drains in their homes so that adds complexity. Seigenthaler a big advocate for these units, is very careful to point out that air to water has to be part of system including a buffer tank. So a typical air to water install is 15 to 20 K install to do it right which is a much harder to sell.
if one really wants this to take off easy retrofits for central air systems should be an option. The diy opportunities for a system that can be run with pex should not be overlooked. No need work on any high pressure lines or evacuate the system. Drop ship a an outdoor unit that theoretically is plug and play once all electrical connections are made and filled with glycol(might be the only short coming). (What Tesla has done with the octa valve shouldn’t be overlooked when it comes to these systems that might need heat and cooling at the same time.
The complexity here is in the control. If you really want a combined system it really should require a hot and a cold storage tank for summer.
The complexity here is in the control. If you really want a combined system it really should require a hot and a cold storage tank for summer.
That was the first thing I looked for. The company has ducted air handlers listed on their website. These can be vertically or horizontally mounted.
Definitely right. Running a chiller at 120º would be on the high end for these units 105-110º might be more typical. A system would need a lot of radiator surface area to work at that temp. A better option in some cases would be to replace the baseboard with a fan/coil unit, hopefully reusing the existing piping.
The ability to use both ducted and ductless units is really neat. Radiant floor heat in the winter and AC from a fan coil.
System design would be very important
“If you don't prefer a ducted system, consider our ultra-high efficiency DC Inverter ductless room fan coil units for better efficiency and individual room zoning. Note, you can also mix and match - for example, you may decide to use a ducted orconcealed ceiling fan coil in an open area of your home such as a combined living room-dining room-kitchen, or a great room, etc. and then also use ductless room fan coil units for bedrooms, office, den, or other individual rooms. In addition, either ducted or ductless,or a combination of these, can be used along with radiant heating, domestic hot water, etc. with the Chiltrix air to water heat pump.”
PassionForFire&Water
Minister of Fire
I installed a Spacepak air to water heat pump Solstice
Spacepak is a Mestek brand
I'm only using it for cooling
Heating in winter with windhager BioWIN2 pellet boiler.
There are several other brands availalble.
What I learned:
- make sure there is good customer support (very very poor support from Mestek); you will need it
- It looks easy, but it is not
- these units require lots of gallons per minute water flow (pressure drop coils) = big circulators = $$$ electrical cost
- large water flow also = large diamter piping = $$$
- put your money in a good outside unit and install the cheaper high wall units inside; no bels and whissels; just on/of on room temperature control
PM me if you have specific questions.
Spacepak is a Mestek brand
I'm only using it for cooling
Heating in winter with windhager BioWIN2 pellet boiler.
There are several other brands availalble.
What I learned:
- make sure there is good customer support (very very poor support from Mestek); you will need it
- It looks easy, but it is not
- these units require lots of gallons per minute water flow (pressure drop coils) = big circulators = $$$ electrical cost
- large water flow also = large diamter piping = $$$
- put your money in a good outside unit and install the cheaper high wall units inside; no bels and whissels; just on/of on room temperature control
PM me if you have specific questions.
