Gas or electric fueled hydronic heating systems

Hydronic heating systems use water to distribute their heat through the house. In such a system, water is first heated by either an electric or gas fired boiler and then pumped through a system of pipes to all areas of the house to give off its heat to the rooms before returning to the boiler to be reheated.

The heat transfer within rooms may be done by either running the water through baseboard convectors or through radiant piping within the floor system. In either system, it is important that a proper room by room heat loss calculation and design be done to ensure the correct amount of heat is delivered to each space. Consideration should be given to how the design is zoned (separated into heat distribution areas) to allow for maximum temperature control on a zone by zone basis.

This method of heat distribution is usually more costly than forced air but it is reported by R-2000 homeowners to be one of the most comfortable for occupants as a more constant source of heat is provided to the space.

Hydronic heating does not promote airflow and therefore must be associated with a fully ducted heat recovery ventilation system to provide ventilation air to all rooms.

Using this method of heating limits air conditioning options to through the wall or window type units. Because the air in the home is not circulated by a furnace fan, filtering of particulates from the air is not possible with a conventional central filter system. If required, it must be done on an individual room basis with table top type room air filtration devices.

Hydronic heating is gaining in popularity in Manitoba due to its positive impact on interior comfort. Contrary to a lot of industry provided consumer marketing information, evidence indicates this system is only marginally more efficient (5% – 10%) than more standard forced air heating systems.

Ground sourced heat pump systems

A ground sourced heat pump uses a series of pipes buried in the ground or groundwater, to extract the heat from the earth for use in the house. Since the ground or groundwater remains relatively constant in temperature throughout the year (well above outdoor temperatures in winter and below them in summer), it provides a constant heating or cooling source for the pump to heat or cool the house. A heat exchange coil containing a refrigerant within the house extracts the heat from the ground loop liquid, turning it into usable heat for the home. A fan moves air over the heat exchanger and distributes the conditioned air through a system of forced air ducts around the house. In summer months, the process is reversed to provide cooling.

This is the most efficient method of residential heating available on the market. Depending on the efficiency of the heat pump unit (coefficient of performance COP), it can provide up to three or four kilowatts of heat for every kilowatt of electricity used to operate the unit.

Ground sourced heating allows for easy interconnection with an HRV system, a central air filtration device and provides integral air conditioning. The heat pump can also be interconnected with a water heater to assist in heating the domestic hot water.

This method of heating is associated with a fairly high initial capital cost. HOT2000 analysis done on many R-2000 Homes considering the ground source heat pump option seems to indicate that this system does makes economic sense and has a positive cash flow payback in larger or less efficient houses that use more heat energy. Smaller energy efficient homes have such a low requirement for heat, it may not make economic sense to pay a lot of money for the most efficient heat system to meet those modest needs.

A HOT2000 computer energy analysis can help provide you with the information you need to make the most informed decision as to whether this or any other heating system is right for your new R-2000 house.