AQUATHERMAT® with oil or gas hot water heater

The use of an oil or gas fired water heater as a heat source is economical and suitable for medium growing surfaces.


  • A temperature sensor inserted in the substrate is used by the control system to calculate the supply temperature required to keep the soil at the proper set point.

  • The use of a mixing valve is necessary as it is not possible to modulate the boiler outside of a very narrow permissible temperature range.

  • An expansion tank and a pressure regulator (12 PSI) must be installed in order to protect the mat's hot water conducts.

  • The by-pass valve is used to adjust the circuit pressure.

  • The circulation pump must be activated at all times in order to keep an even temperature across the mats.

  • The purge and shut-off valves are most useful to bleed the air out of the system at start-up.