How to Adjust a Pneumatic Thermostat

How to Adjust a Pneumatic Thermostat – Learn how to adjust a pneumatic thermostat for your home or office by following these simple steps.

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A pneumatic thermostat is a type of temperature control device that uses compressed air to operate a switch. Pneumatic thermostats are commonly used in industrial and commercial settings to control the temperature of air conditioners, furnaces, and other types of heating and cooling equipment.

Pneumatic thermostats are available in two basic designs: those with a diaphragm-type sensing element, and those with a bulb-type sensing element. Diaphragm-type pneumatic thermostats are more accurate than bulb-type pneumatic thermostats, but both types are suitable for most applications.

What is a Pneumatic Thermostat?

A pneumatic thermostat is a device that uses pressurized air to automatically regulate temperature. These devices are commonly used in HVAC systems to keep rooms at a comfortable temperature by opening and closing dampers in the ductwork. Pneumatic thermostats often have an adjustment knob that can be used to fine-tune the temperature set point.

How Does a Pneumatic Thermostat Work?

Pneumatic thermostats are devices that use compressed air to control the temperature of a room or space. They work by sensing the temperature of the air around them and using a series of valves and chambers to regulate the flow of air into and out of the room or space. By doing this, they are able to maintain a consistent temperature.

Pneumatic thermostats are often used in industrial settings, as they can be very precise and are not affected by electrical fluctuations. They are also relatively simple to install and operate.

Why Use a Pneumatic Thermostat?

Pneumatic thermostats are commonly used in HVAC applications to control room temperature. They are more accurate than electronic thermostats and can be mounted remotely from the space being controlled, making them ideal for controlling temperature in hard-to-reach places.

Pneumatic thermostats work by sensing the air temperature and then sending a signal to the HVAC system to turn on or off as needed to maintain the desired temperature. These thermostats can be used with a variety of HVAC systems, including forced air, hydronic, and steam systems.

How to Adjust a Pneumatic Thermostat

A pneumatic thermostat is a temperature-controlled switch that uses air pressure to activate or deactivate a heating or cooling system. Pneumatic thermostats are often used in large buildings with complex HVAC (heating, ventilating and air conditioning) systems. If the temperature in a building is too hot or too cold, the pneumatic thermostat will activate the HVAC system to make the adjustment.

Pneumatic thermostats can be adjusted manually or automatically. Most pneumatic thermostats have an automatic feature that will adjust the temperature based on the outside temperature. If you want to adjust the temperature manually, you will need to use a screwdriver to turn the screw on the side of the thermostat. Turn the screw clockwise to increase the temperature and counterclockwise to decrease the temperature.

Tips for Adjusting a Pneumatic Thermostat

If you have a pneumatic thermostat in your home or office, you may need to adjust it from time to time to maintain a comfortable temperature. Here are a few tips for adjusting a pneumatic thermostat:

1. Locate the air vents on the thermostat. These are usually located on the top or sides of the unit.

2. Adjust the air vents to direct more or less air flow to the sensor inside the thermostat. More air flow will result in a higher temperature reading, while less air flow will result in a lower temperature reading.

3. Check the temperature setting on the thermostat. If it is set too low, the unit will cycle off more frequently and may not heat the space evenly. If it is set too high, the unit will run continuously and may overheat the space.

4. Adjust the temperature setting as needed until you achieve the desired comfort level.

Troubleshooting a Pneumatic Thermostat

If you have a pneumatic thermostat in your home or office, you may occasionally need to troubleshoot it when it doesn’t seem to be working properly. Fortunately, there are a few easy steps you can take to get your thermostat back up and running.

First, check the batteries. If the batteries are low or dead, the thermostat may not work properly. Replace the batteries with fresh ones and see if that solves the problem.

If the batteries are fine, then check the air pressure. The air pressure should be between 20 and 30 psi. If it’s lower than that, then you’ll need to add more air. If it’s higher than that, then you’ll need to release some air.

You can also try resetting the thermostat by turning it off and then on again. This sometimes solves minor issues.

If none of these troubleshooting steps work, then you may need to replace the entire thermostat.


Thank you for taking the time to read this guide on how to adjust a pneumatic thermostat. We hope that you found it informative and helpful. If you have any questions or concerns, please do not hesitate to contact us.


Before You Start:
-Pneumatic thermostats are used to control the temperature of a space by regulating the flow of air.
-They are often found in HVAC (heating, ventilation, and air conditioning) systems.
-Pneumatic thermostats can be either manual or automatic.
-Manual pneumatic thermostats require you to adjust the settings yourself, while automatic pneumatic thermostats will adjust the settings based on the temperature of the space.

What You’ll Need:
-A pneumatic thermostat
-Tape measure


1. Locate the pneumatic thermostat. It will usually be mounted on a wall near the area that it is regulating.
2. Use a screwdriver to remove the cover of the thermostat. Be careful not to lose any small parts.
3. Locate the adjustment knob inside the thermostat. This is usually a small knob that can be turned in either direction.
4. Turn the knob to the left to decrease the temperature, or turn it to the right to increase the temperature.
5. Test the new setting by measuring the temperature of the space with a thermometer.
6. Adjust as necessary until you achieve the desired temperature

About the Author

Hi, my name is Jesse Sessler and I am a HVAC Technician. I have been in the field for over 10 years and have seen a lot of different systems. In this guide, I will show you how to adjust a pneumatic thermostat.

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