Frequently Asked Questions

What is an Air To Water Heat Pump? (a/k/a AWHP, ATWHP, Reverse Cycle Chiller, or Hydronic heat Pump)

An ATWHP is a special type of ultra-high efficiency heat pump that is self-contained (keeps all of the refrigerant outdoors in the outdoor unit) and connects to indoor heating, cooling, or hot water loads or equipment via insulated PEX water lines. ATWHPs are used with any, all, or a combination of radiant heating, radiant cooling, ductless room fan coil units, duct system air handlers, and hot water heater tanks (indirect type).

Does the air to water heat pump chiller heat pump consume water?

The Chiltrix air to water heat pump (reverse cycle chiller) does not consume any water and works in all humidity conditions. It uses a ultra-high efficiency DC-Inverter variable speed compressor with a small amount of R410a refrigerant self-contained in the outdoor unit. The water or water/glycol fluid is only used in a sealed loop, to transfer heating or cooling between the outdoor unit and the indoor units. Actually, a chiller is defined as a split system where water or water/glycol lines connect the indoor equipment to the outdoor equipment.

How many indoor units will the chiller support?

In general, the Chiltrix air to water heat pump chiller can support any number of indoor units, that together, do not exceed the BTU capacity of the chiller(s). It is also possible to use more indoor units than the math supports, as long as you realize that they cannot all run at full speed at the same time and still deliver the expected cooling or heating. For a list of all available indoor units and their BTU ratings please see chiller indoor units. You can select HW (standard efficiency 220v) or CXI (ultra-high efficiency 120v) indoor fan coil units from Chiltrix, or use any standard chiller fan coils. Note, the HW units are mainly for export, for USA please use the CXI units.

What different size systems are available?

Chiltrix has 2 sizes of outdoor units - the CX34 with 2 tons cooling, 2.75 tons heating, and the CX50 with 3.5 tons cooling and 4.8 tons heating. These are modular, meaning that they can be combined in any combination to achieve systems up to 10.5 tons cooling and 14.4 tons heating.

Can I use it with a ducted or central system?

We offer ducted AHU (hydronic air handler units) for ducted systems.. These connect into a ducted system in the same manner as a regular AHU. You can see more information here. In addition, you can use any standard fan coil ducted unit/hydronic air handler of the correct capacity that you may purchase on the open market, they are available through most HVAC supply houses. Please contact us to help with sizing this type of unit as the sizing will be non-standard.

How does A Chiltrix system compare to a multi-head or VRF mini-split system?

  1. Same or better heating performance, better cooling performance.
  2. Ability to totally integrate variable backup heating, no “heat strips” or portable heaters ever needed.
  3. Ability to also perform domestic water heating.
  4. Ability to work with radiant heating (and/or radiant cooling in most climates).
  5. Can work with any or all of ductless, central duct, mini-duct, radiant, water heating, all in the same application.
  6. No refrigerant handling, self-contained outdoor unit is an “appliance”, enables DIY or lower-skill installation.
  7. No refrigeration license needed, can be installed by HVAC, plumber, skilled handyman, certain homeowners.
  8. No refrigerant is ever inside the building envelope.
  9. Indoor-side system, once installed, is future-proof and uses a water or water/glycol mix, it is compatible with future technologies, and next-gen refrigerants that you definitely don’t want indoors. The newer high-efficiency and environmentally friendly refrigerants tend to be highly toxic and/or flammable (refrigerants such as R32, R290, etc,. this is stuff that you don't want inside the building envelope).
  10. No arbitrary line-set length limits or vertical lift limits.
  11. Multiple indoor head units possible - up to 12 or more indoor units, according to the loads and design.
  12. Leaks - in a multi-head (or VRF) mini-split system, if there is ever a leak, you may need to rip down a lot of drywall to find it. Not bragging about leaks, but with mini-splits that can happen from time to time. With water, if a leak were to occur it will be immediately obvious and you will know where a leak is, as a few gallons will come out before the unit stops itself. Of course with a PEX system, there are rarely if ever leaks. With PEX piping, which is also commonly used for normal plumbing, you should not ever have a leak.

What about Comparison of Chiltrix to EVI Compressor Units?

For most users in the USA, an EVI compressor will not result in any annual savings. In general, EVI compressors have better performance at very cold temperatures, but sacrifice efficiency during the milder part of the heating season and have poor cooling performance. If you are in a climate where more than 15% of your annual heating hours are below 0F there may be some advantages to EVI. Please contact us for the ASHRAE Hourly Normals report for your nearest weather station, we can show you how many hours you will have per year at each temperature. Only in extreme elevations do we see advantages in USA for EVI compressors. Even in Canada, or coastal Alaska, EVI usually calculates out to higher annual energy use.

What about floor heating (Radiant Heating)?

Once you have experienced the comfort and efficiency of in-floor heating, you may never again be satisfied with any other type of heating. Chiltrix is highly compatible with hydronic floor heating and is designed to deliver an optimum floor heating experience. Chiltrix can work  with in-floor radiant or radiant in walls or ceiling, or with radiant panels. And radiant can be used in combination with other means such as fan coils, air handlers, etc.

We also have customers using the Chiltrix system for "radiant cooling" which works well when used with a dew point controller.

What about Radiant Cooling? (And Radiant Cooling Dew Point Control?)

Like radiant heating, radiant cooling can be far more comfortable, increase indoor air quality, and can be the most efficient cooling choice available. Chiltrix is highly compatible with radiant cooling and produces a special radiant cooling controller that can ensure that the system works at maximum capacity while never producing a radiant surface below the dew point. Care must be taken in regards to dew point control, to prevent unwanted condensation. Please see more here about radiant cooling

What is the SEER rating?

There is no US DOE, EnergyStar, or other SEER test or rating for air to water heat pump chillers. ATWHP units are rated under AHRI 550/590 which does not include SEER and are rated with IPLV. IPLV is to chillers what SEER is to standard air conditioners. It's the official AHRI efficiency rating and it's the only rating that matters for chillers. IPLV is the industry-standard way of measuring the overall efficiency of a hydronic (chiller) cooling system. IPLV stands for Integrated Part Load Value, it's a similar concept to SEER, where part-load performance is measured and rated so that customers can have a way to do an apples-to-apples comparison of real-world operating efficiency between various brands and models. IPLV and NPLV are specified in AHRI 550/590. See the product page or spec sheet for the IPLV / NPLV of the specific chiller. See a more complete explanation of IPLV See a chiller IPLV comparison chart that shows how we stack up against the competition.

What is the HSPF Rating?

As with SEER, air to water heat pumps do not have a HSPF rating since HSPF is not available under AHRI 550/590. However, SCOP is available under IEC EN14825. For example, the CX50 is also certified under EN14285 where it has a SCOP of 4.55, which converts to an equivalent HSPF 15.51. But note, this is not a HSPF rating, only an equivalent.

How about Dehumidification?

Like all air conditioning systems, when the cooling coils are below the dew point, dehumidification is performed. The Chiltrix system performs strong dehumidification comparable to a standard air conditioning system. And when used with DHC (Dynamic Humidity Control) the Chiltrix system can lower the coil temperature well below the standard condition to perform hyper-dehumidification and can also turn off dehumidification when not needed, to save energy..

What is the Psychrologix™ Controller?

The Psychrologix™ is a very unique and special controller. It is a programmable indoor controller that automates many features such as chiller reset, auto-changeover from cooling to heating, alarms, vacation mode, and many other features and includes the DHC (Dynamic Humidity Control) function. Note, this controller is not a thermostat, all thermostat functions are handled by the individual fan coil unit thermostats or in the case of ducted systems, by a standard thermostat.

What is DHC/Dynamic Humidity Control?

DHC control can automatically manage the chiller cooling parameters to increase or decrease, or stop, dehumidification. If indoor humidity rises, the system can automatically decrease the coil temperature to a lower temperature so as to perform accelerated dehumidification. During times when humidity is within the ASHRAE recommended range, the DHC will "turn off" dehumidification, allowing the system to continue to manage sensible (regular thermometer) temperature at a greatly reduced power consumption level. Indoor humidity occurs after an event such as a exterior door opening on a humid day, or taking a hot shower. Once removed, humidity will not increase again on its own, until the next humidity event occurs. Chiltrix's efficiency can increase up to 50% above it's exceptionally high official EER ratings during periods when dehumidification is not needed.

What's involved in installation?

The chiller outdoor unit needs a stable mounting position like a concrete pad, a power connection, and insulated water lines connected to the indoor unit(s). Usually 1" PEX flexible water lines are used for this. No refrigeration technician, gauges, extra refrigerant, or special tools are needed. Mainly, you need an electrician to provide a 208-240 50/60Hz power connection of >/= 15a (per ODU) and then make your water line connections. Each indoor unit is powered separately using standard household power (available as 120v or 208-240v, please review the specs of the selected indoor units). Other than that, you will install the water lines and may add a small expansion tank, some fittings, etc. depending on the design. Longer water line runs or complex routing may require a small booster pump which we can provide, contact us with your design to confirm. Recommended for water lines is oxygen-free PEX which is available from Home Depot or Lowes, etc. Standard loop design using accurate measurements can naturally achieve a system pressure balance. See chiller installation manual.

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.

What about backup heat for extra-cold days?

Some locations may need backup heat, this will be known form the Manual J report. Integrated backup heat is another thing that makes Chiltrix unique among mini-split systems since the backup heat can be seamlessly incorporated into the system, avoiding, for example, the need for portable heaters. Like all heat pumps, heating capacity is reduced as outdoor weather gets colder. If you live in a very cold climate you may need backup heat occasionally. The globally-accepted way to add backup heat to a hydronic heat pump system is to use a normal water heater (like from Lowes or Home Depot) installed on the supply line. When backup heat is needed, the chiller can enable the tank heater that runs based on its own thermostat.

Chiltrix also offers an advanced, highly-efficient fully integrated backup heater, the V18. The V18 provides dynamically variable backup heat that precisely adds just the right amount of backup heat into the system based on the actual, real time capacity and load differential. Rather than chasing and overshooting a thermostat, the v18 receives communications from the Chiltrix heat pump to adjust power and exactly match any BTU shortfall in real time. The V18 installs in-line as a precisely modulating tankless heater with almost zero pressure drop. See more info...

Why is capacity lower when outdoor temperatures are lower?

ALL heat pumps, including Chiltrix, have reduced capacity at lower ambient temperatures. The factor that has the largest effect on efficiency,is the amount of "lift", i.e., the delta T between the ambient and the heat pump operating outlet temperature. As ambient drops lower, the lift becomes higher. This is why Chiltrix helps design systems that can work properly with the lowest amount of lift. The advantages of lower lift is explained by the following Carnot calculation where (T¹- T²) is the amount of lift..

image of carnot calculation for heat pumps

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.

What kind of hot water tank is used?

A heat pump such as Chiltrix needs an "indirect" tank, such as a boiler tank or a solar tank, this is a tank with a coil inside. Of course we suggest our DHW80 or DHW40 tanks as they are very high spec tanks made with duplex 2205 grade stainless steel and have a industry-leading over-sized coil with a very large surface area. if you provide your own water heating tank, make sure of the following: it must have at least .35 ft^2 coil surface area per gallon, and, an inside diameter not less than 1". And make sure it has a provision for a backup heating element so you can take full advantage of our automated anti-legionella function.

What about recirculating hot water systems?

We don't ever recommend recirculating hot water systems, in general, they waste energy in order to save water and for most people the economics are better to not waste the energy. And we don't suggest them for Chiltrix, as this type of system puts a continuous parasitic load on the DHW tank . If you decide to use recirculating hot water with Chiltrix we suggest to only use it with very well-insulated water lines and a "smart" recirc system such as those that have a call" button or motion sensor, for example, AquaMotion.

Can I use it to unload or replace an existing boiler?

Yes, the Chiltrix air to water heat pump chillers can provide very low cost heating when compared to an electric, propane, or oil fired boiler. You can configure the chiller as primary and only run the boiler if needed.

Can Chiltrix support old-style radiators or baseboard heaters?

Generally radiators are designed to receive very hot water, as high as 180F. No heat pump including Chiltrix will operate at those temperatures. For example, if using Chiltrix at 105F with a radiator rated at 160F, the radiator capacity will be reduced to a factor around 37% of the original rating. Usually radiators are replaced with fan coil units, in many cases the existing piping can still be used.

How do I know if my existing radiator piping can be used when upgrading to ductless fan coil units?

Please see this document.

What about using it for a server room or computer room?

It's perfect, actually the Chiltrix air to water chiller development started out as an effort to design the worlds most efficient air conditioner for small computer rooms/server rooms, and it succeeded beyond our expectations. The server room version also has an available "free cooling" option that in cold weather, can allow the system to run at its full rated capacity with the compressor off, running only fans and water pump saving a large amount of energy cost without bringing in any outside air. Free cooling COP can be as high as 41 (EER 140) during cold weather periods. See more info on free cooling. In addition, the stackable design of the Chiltrix chiller system allows for a highly redundant N+N configuration.

What are the power requirements?

The system is designed for global use and is therefore very flexible. It can use voltage between 208v to 240v, and can use either 50Hz or 60Hz power. Indoor units (IDUs) are a little different - we offer 60Hz IDUs for 110v to130v. We also offer a 208-240v unit that can run on 50Hz or 60Hz. So wherever you are and whatever kind of power you have, we have a solution. A 20a circuit is needed.

What kind of refrigerant is used?

The CX34 uses R410a in the outdoor unit (ODU). Other Chiltrix models use R32.

What external controls can be used?

The CX34 standard included controller is all that most people would ever need. In addition, we offer the Psychrologix controller option for dynamic humidity control. Further, customers have the ability to control the CX34 by relays (such as from a standard single-stage heat pump thermostat). And for advanced users, we offer the (free) ability to control the CX34 via Modbus RTU (can be used also with BACnet gateway).

What kind of maintenance is needed?

Unlike chillers that have a cooling tower, the Chiltrix air to water heat pumps are air cooled like a regular air conditioner and such, only require the same periodic coil cleaning as would a standard AC/heat pump. It is a sealed outdoor appliance, there are no user-servicable parts inside, and no need for servicing. Any indoor fan/coil units need to have their filters removed, cleaned, and re-inserted on a regular basis. You can determine the frequency of this requirement based on the filters appearance (and your air quality).

What is the expected life span of the system?

The system is engineered using best-of-breed components sourced from top providers around the world. German brand Wilo VSD water pumps, USA valves, heat exchangers from (SWEP) Sweden and (Multi-Stack) Australia, electronics from Japan, Mitsubushi compressor (Japan) and Panasonic variable speed fan (Japan), and the list goes on. All components are selected based on reliability and performance. The system is easily serviceable and is designed for a 20 year lifetime.

What minimum and maximum range of ambient temperatures are supported?

The standard system is designed for low ambient heating and cooling, and supports standard high ambient cooling conditions. Heating is available from as low as -4F (-20C) or below. we only have test data to -4F however under certain conditions the unit can operate as low as -17. Cooling range is rated up to 122F (50C). The unit can provide cooling at a reduced capacity up to 138F (59C).

How long can the lineset be?

There is no refrigerant lineset needed or used with the Chiltrix self-contained chiller. All of the indoor units are connected to the chiller using standard insulated CPVC or PEX (or similar) water line. The water line can be any length up to hundreds of feet. To calculate the actual distance we need to know the plumbing design and which indoor units are being used (so we can know the pressure drop spec). But regardless, an inexpensive Chiltrix-provided variable speed booster pump controlled by the chiller can provide a virtually unlimited allowable line distance.

What is the warranty?

The Chiltrix Limited Warranty is 5 years on the compressor and 2 years on other components. See warranty.

Is the unit certified?

The unit is fully certified for USA and Canada and has obtained approval under UL 60335-2-40 and CSA 22.2. These certifications are recognized in over 90 countries worldwide. If you need other international certifications such as SAA, CB, CE, SONCAP, etc. we can provide any of these on quantity orders.

ahri small logo

TUV logo

Further, the CX34 is AHRI-certified. AHRI is the official, independent 3rd party testing & certification organization used by the global HVAC industry and by government regulators worldwide. When AHRI certifies that a unit has a particular capacity or efficiency level, this certification is indisputable evidence that the performance stated by the manufacturer is accurate. Chiltrix units are also certified for Europe by TUV where they hold an A+++ rating, the highest possible rating.

Chiltrix is also certified by the California Energy Commission (Titles 21, 24).

How much do they cost?

Please see the chiller heat pump air conditioner price list.

What is a DC-Inverter drive?

Whether it is used for a compressor, a pump, or a fan motor, DC Inverter motors are recognized as being more efficient, mainly because they use less power and can infinitely adjust their speed in real time to match the current demand. They also run cooler, last longer, and make far less noise.

DC Inverter motors actually have no inverter in them, this is a poor name that was applied years ago and has remained in use. Actually, AC power runs through a rectifier circuit converting it to DC power.

DC inverters are not only more efficient at a given speed, but having the ability to match the speed to the current application saves even more power.

chart comparison of efficiency between DC inverter motor and AC motor

Who are you people?

We are Chiltrix Inc., a Virginia corporation and an affiliate under common control with HotSpot Energy Inc. (www.hotspotenergy.com). Chiltrix is distributed in North America by HotSpot Energy Inc.

 

 

Did You Know?

Chillers use much less energy, and also use 50% to 90% less refrigerant to accomplish the same amount of heating or cooling. That's because no refrigerant lines are used inside the building to distribute heating and cooling - this is done by a water-glycol mix. All of the refrigerant stays in the outdoor unit.

That means that lineset length is virtually unlimited. It also means there are no high-pressure lines inside the building, which is a good thing for safety.

Self-contained chillers like the CX34 are user-installable, meaning no refrigeration technician or special tools are needed for installation, resulting in a perfect DIY application..