Hydronic Underfloor Heating| Coatesville

Sumptuous Home Showcases Hydronic Underfloor Heating

Tucked away in Coatesville this 300m2 home is a splendid demonstration of an energy efficient underfloor heating solution. Hydronic underfloor heating offers a comfortable, long-term, and possibly the most sustainable option for home heating, when combined with a Performance Plus heat pump water heater. Using a low energy input from electricity (roughly 80% of which is derived from renewable sources in NZ) it meets the increasing drive to protect our resources for future generations.

A Heating solution for all floors

The home owners were building from scratch for the third time. For their first home they used gas to heat the house. Champion Heating installed a 7GP30Ub24-3 Duoheat heat pump to heat the pool and underfloor in their second house. So it was an easy choice to use Tony Champion again for the underfloor heating in this house. Tony's solution was one Performance Plus 7GUb16-1 Digital Scroll heat pump for the entire underfloor. For a house of this size, two heat pumps are often recommended to minimize heat loss that occurs over a more extensive space. The owners preferred to minimise the visual impact of the heat pump, so a single pump was used. The mains flow and return pipes were protected in an insulated duct which was trenched underground to reduce heat loss. The heat pump was then discretely positioned on the far side of the barn.

A Ribraft floor, comprised of polystyrene pods, insulates the ground and concrete making up the base of the house. The floors include tile, wood and carpet surfaces. Each area has been divided into thermostatically controlled zones (shown on the plan below) where individual controls for each zone exploit the system's energy efficiency.

The different characteristics of each floor covering are accommodated so the hydronic system works successfully. Tiled or polished concrete floors provide good heat transfer, in contrast, a carpeted floor requires a low tog rating for heat to rise easily from the slab beneath. Moisture must be removed from the concrete below a wooden floor to ensure the timber does not warp when heat is first released from the concrete.

A slab thermostat was installed in each zone to maintain a constant temperature, minimising expansion and contraction of the wood. Different flooring surfaces were circuited independently of each other to accommodate the variation in heat transfer rates. Digital Scroll technology in the heat pump makes this possible, allowing individual kW output rates that could reduce running costs.

The owners are enjoying the warmth of the house and are 100% satisfied with the results. They happily recommend Champion Heating and the Performance Plus heat pump from Hot Water
Heat Pumps Ltd.