Enjoy improved indoor comfort with an OpenTherm control. London residents, call 020 8882 2266 to configure your system.

What is OpenTherm?

OpenTherm is an independent system of communication between modulating boilers and a controller; normally, this is a room thermostat.

The Problem With Normal Heating Room Thermostats

A normal room thermostat will tell the boiler to fire up the burner when the desired ambient air temperature has not been satisfied.
When the room temperature rises and the room thermostat is satisfied, the call for demand is simply switched off by the room thermostat. The boiler burner goes off and the cycle continues as heat is lost from the property and the room thermostat asks the boiler to fire up again.

There are two problems with this.

1. This can sometimes cause discomfort to the homeowner as the room cools down due to the delay of waiting for the property to be heated again.

2. The boiler is likely burning at a higher rate than needed to reheat the property, causing unnecessary emissions and wasted fuel.

How OpenTherm Controls Work

OpenTherm controls improve this situation by precisely controlling the boiler burner in a much more intelligent way. The OpenTherm controller communicates directly with boiler, giving information on the ambient room temperature. A clever microprocessor then determines at what rate the modulation of the flame should be at the boiler. Rather than simply turning the boiler off when the heating temperature has been met, the OpenTherm controller lowers the output of the boiler to keep a consistent warm house by calculating the heat loss occurring and heat needed from the boiler to keep the house at the desired temperature.

This creates a more comfortable environment and less on–off cycling.

New condensing boilers are at their highest efficiency when the return temperature is 54 – 56°C. OpenTherm controls allow the boiler to operate at this temperature for longer periods. This will help save on C02 emissions and your gas bill!

Contact City Gas Services at 020 8882 2266 for expert advice about OpenTherm controls and how they can benefit your system.

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