Abstract: An electronic circuit for a hot water heating system an override thermostat; a timer operable to deactivate and reactivate the burner while a room thermostat is calling for heat; a differential temperature switch configured to disconnect the electrical supply to the water pump when the difference in temperature between the water at the boiler inlet and the water at the boiler outlet falls below an adjustable set point; and, a temperature switch configured to prevent operability of the timer until the temperature of the water at the burner outlet rises above an adjustable set point.

Abstract: An electronic circuit for a hot water heating system conserves fuel consumption and reduces carbon dioxide emissions. A heating system includes a burner that heats water and a room thermostat. The electronic circuit comprises an override thermostat which has a setting for a lower temperature limit and an upper temperature limit below those of the room thermostat. The override thermostat is operable to activate continuous operation of the burner when the indoor temperature falls below the lower temperature limit of the override thermostat and until the upper temperature limit of the override thermostat is reached. The electronic circuit further comprises a timer operable to deactivate and reactivate the burner while the room thermostat is calling for heat.

Abstract: An electronic circuit for a hot water heating system an override thermostat; a timer operable to deactivate and reactivate the burner while a room thermostat is calling for heat; a differential temperature switch configured to disconnect the electrical supply to the water pump when the difference in temperature between the water at the boiler inlet and the water at the boiler outlet falls below an adjustable set point; and, a temperature switch configured to prevent operability of the timer until the temperature of the water at the burner outlet rises above an adjustable set point.

Abstract: An electronic circuit for a hot water heating system conserves fuel consumption and reduces carbon dioxide emissions. A heating system includes a burner that heats water and a room thermostat. The electronic circuit comprises an override thermostat which has a setting for a lower temperature limit and an upper temperature limit below those of the room thermostat. The override thermostat is operable to activate continuous operation of the burner until the upper temperature limit of the override thermostat is reached when the indoor temperature falls below the lower temperature limit of the room thermostat. The electronic circuit further comprises a timer operable to deactivate and reactivate the burner while the room thermostat is calling for heat.