Can a manometer measure the gas pressure

Manometer for heating: function, setting & costs

The term manometer describes a pressure measuring device. It can be used to precisely measure the pressure of liquids and gases. These devices are indispensable in heating technology. On the one hand, this measurement technology is installed directly in the heating system in order to monitor the operating pressure. On the other hand, tradespeople carry mobile pressure measuring devices with them, for example to check the pressure at the connection during a new installation.

Different types of measurement

Pressure can be determined in several ways. Liquid manometers such as the U-tube manometer are widespread. A suitable liquid, including mercury, is used as the measuring device. It fills the U-tube halfway. Moving this so-called barrier fluid shows the pressure. Alternatively, the measurement is often based on spring technology. This applies, among other things, to many measuring devices built into heating systems in which a Bourdon tube controls the pointer.


Overall, pressure plays a major role in heating systems. In a gas boiler, for example, the gas pressure at the connection must be correct, otherwise the system will not work. With regard to the functionality of all heating systems, the water pressure in the heating water circuit is of central importance. If it is too low, not enough heated water will run through the pipes into the radiators. Too high a pressure can cause permanent damage. Users can solve both problems by either adding or draining water. Detailed information can be found in the operating instructions.

The standard pressure gauge on the heater

Pressure gauges for heating systems usually have a dial that shows a pressure range between 0 and 4 bar. A green field on the dial shows the permissible or optimal range. The red pointer can be set statically, it acts as a warning signal.

The black pointer moves thanks to the spring technology and indicates the current pressure. In this way, you can always monitor whether there is a need for action. If the black pointer exceeds the red one, there is no imminent danger. You don't have to expect immediate damage. However, you should avoid this problem, as in this case you will not be heating ideally.

Measurement when installing a new heating system

Craftsmen carry out a pressure measurement at the connection during installation. Every heating system is designed for a specific pressure range. The pressure at the connection must neither fall below nor exceed this range, otherwise commissioning must not take place. Normally there are no problems because the gas supplier guarantees a certain pressure and consumers buy the right heating system on this basis. However, defects in the pipe system can cause deviations in the immediate vicinity of the building.


The liquid-based manometers with analog display are comparatively simple devices, similar to a thermometer. That is why, for example, pressure gauges for heating do not cost more than 10 euros. You have to plan a higher double-digit amount for a digital pressure gauge.

Replace the pressure gauge

If the pressure measuring device in the system shows a malfunction, you can change it yourself. All you have to do is unscrew the old device and screw in the replacement.