How air to water hydronic heat pump systems work using Chiltrix.
Most air conditioners and heat pumps sold in the U.S. & Canada, including most split-system air conditioners and ductless mini splits, are air-to-air heat pumps. During the winter, these appliances extract heat from the outdoor air and deliver warm air to a house through ducts or small fan-coil units. During the summer, these appliances deliver cool air to a house and dump unwanted heat into the outdoor air.
Another type of heat pump, an air-to-water heat pump, produces hot water (or chilled water). When used for air conditioning, an air-to-water heat pump is called a chiller. Almost all air conditioners cool an air stream by blowing air past a copper coil. In a conventional split system air conditioner, called a DX (or “direct expansion”) system, the fluid in the copper coil is a refrigerant. In a chiller-based system, however, the fluid in the copper coil is water (or in some cases, a solution of water and antifreeze).
When used for space heating, an air-to-water heat pump fills the role usually held by a boiler; it requires a hydronic (water-based) distribution system. The heat pump makes hot water; the hot water can be pumped through fin-tube baseboard units, in-floor PEX tubing, or a fan-coil unit. (A system with such a fan-coil unit is called a hydro-air system.) The fan-coil unit can be a small wall-mounted unit that looks like the indoor unit of a ductless minisplit system, or it can be a large fan-coil unit connected to a conventional forced-air duct system.
Premium comfort features:
- Record Setting Efficient
- Officially rated with an IPLV EER 23, the CX34 efficiency is 37% higher than its nearest competitor.
- Flexibility
- Best of Breed Components
- Variable Capacity Control
- Dynamic Humidity Control
- Integrated Backup Heat
- Onboard Outdoor Reset Control
- Solar Options
- Anti-corrosion
Chiltrix CX34 Fact Sheet
Chiltrix CX34 Overview
CXI DC Inverter Fan Coil Units
Chiltrix V18 Hydronic Backup Heater




Sub Zero is a family-owned and operated mechanical contracting business.
SUB ZERO HEATING & COOLING Ltd.
636 Charlotte Street Duncan, BC, V9L2V6
250-597-8097
Serving the HVAC needs of Vancouver Island and the Gulf Island communities with honesty and integrity.