They are operated daily in winter and are part of a modern heating system: Thermostatic valves regulate the heating phase for radiators and help save heating costs. Learn how thermostats work, how they are correctly operated, and what funding is available for radiator valves.
A radiator thermostat is now practically standard on every heater. Maybe that’s one reason why the inconspicuous thermostats are often underestimated. Although everyone knows and uses the cylindrical plastic handles on the radiator, few know how radiator valves work and, above all, how they are set correctly.
This is how thermostats work.
The radiator thermostat consists of a lower part in which the valve is located and a so-called thermostatic head. There is also the centerpiece: a temperature sensor filled with liquid or gas, which controls the opening and closing of the valve. If it is set warmer in the room than at the thermostat, perhaps because the sun is shining through the window, the liquid expands and closes the valve. Lessor no hot water flows through the radiator. When it gets colder, the liquid contracts and a so-called transfer pin opens the valve. Hot water flows into the radiator, which can give off more heat. This happens until the set temperature is reached.
Manually adjustable thermostats
By turning the thermostatic head with the five-level numerical scale, the corresponding desired temperature can be set manually in each room. Switched to the right (step 1), the thermostat is screwed closer to the valve, the opening of the pipe is limited, and the room air temperature is lowered. Turned to the left (step 5), the valve is opened more. Thus, more heating water can flow through the radiator, and the set room temperature is higher.
As a rule, stage 1, regardless of the make, means a room temperature of about twelve degrees. Each additional level brings three to four degrees more.
Like most technical devices, the thermostatic valve also wears out over time—the accuracy of the temperature control and efficiency decrease. For the layman, it is often difficult to tell if the thermostatic valve is exchangeable or defective. Whether the exchange of your thermostats pays off is demonstrated by the Thermostat Check. In conjunction with a hydraulic balancing, there is also a promotion for new thermostatic valves.
Programmable thermostats can do more.
Programmable heating thermostats work in the same pattern. Only that here instead of a liquid, an electronic sensor measures the temperature and the radiator valves are not controlled purely mechanically, but via an electric motor. They regulate the room temperature according to the time. So the bath is warm in the morning for showering but cools during the day – when it is not needed – at an economical 16 degrees. On average, about ten percent of heating costs can be saved. Another advantage: The devices are also suitable for tenants.
Particularly in the case of electric radiator thermostats, the manufacturers come up trumps each year with new and more modern variants. While simpler models are set directly on the thermostatic head, newer models can be set via radio or Bluetooth via PC or App. The advantage: sometimes settings can also be made remotely, for example, on the way home.
Presettable radiator valve and hydraulic balancing
Conventional radiator thermostats often have a Voreinstellungsmöglichkeit for the craftsman – a so-called presettable thermostatic valve. A set screw in the valve body determines how much heating water – regardless of the setting of the thermostatic head – flows through the valve at maximum. Thus, the flow in the radiator can be limited and adapted to the actual needs of the room.
These presettable thermostats are an essential prerequisite to being able to set the heating system optimally and energy-saving using hydraulic balancing . Especially owners of one- and two-family houses can thus optimize their heating cost-effectively. How much you can save, says the Warm Check.
Our photo gallery of pre-settable radiator thermostats will show you how to recognize this type of valve and differentiate it from conventional regulators.
Funding for heating optimization: 30 percent subsidy
As an efficient heating system saves a lot of CO 2 compared to old models and thus makes an essential contribution to climate protection, the Federal Government supports the optimization of older heating systems. Eligible, for example, the hydraulic balancing, whereby the necessary components for the adjustment – such as presettable thermostats – subsidized. Since August 2016, there is a 30 percent subsidy on the net cost. What you have to look out for when applying for grants is explained in the article ” Funding for heating optimization.”