Possible areas of application

We manufacture pressure gauges specifically designed for use in refrigeration and chiller systems and specifically adapted to this application. They have scales showing both the pressure and the pressure-dependent evaporation temperature of the corresponding refrigerant. Some of these pressure gauges also have additional safety features according to the hazard classification of the refrigerant.

Description

Safety pattern version
Refrigerants are classified into three groups according to VBG 20 Sect. 3:

• Group 1: Non-flammable refrigerants with no harmful impact on health
• Group 2: Toxic or corrosive refrigerants and refrigerants with a lower explosion limit of at least 3.5 % by volume when mixed with air
• Group 3: As group 2, but with an explosion limit below 3.5% by volume

SIKA refrigeration pressure gauges comply with EN 837-1 safety level S2 for refrigerants in groups 1 and 2 and EN 837-1 safety level S3 for refrigerants in group 3.

Scales
Our gauges are available with standard display ranges of -1...15 bar, -1...24 bar and -1...30 bar. The scale plates are printed with combined pressure and temperature scales. The pressure scales are in bar, kPa / MPa or psi; the temperature scales are in °C or °F and match the evaporation pressure curve of the corresponding refrigerant. The temperature scales are implemented as „dot scales“ and are usually printed in colour. Gauges with scales for more than one refrigerant can be supplied on request. SIKA offers a wide variety of ready-made special scales for individual measuring ranges and refrigerants. Please contact us to discuss your needs.

Connection threads and materials
All pressure gauges have standard G¼ B or G½ B thread (also available with NPT thread). As an option, we can supply pressure gauges with ¼“ flare connection according to the diagram. The components in contact with the medium being measured are made from brass or bronze. Non-ferrous metals are not allowed in gauges for use with ammonia refrigerant (R717, NH3), so stainless steel alloys are used for this purpose.

Case
Cases of refrigeration pressure gauges can be painted in colour on request to enable the gauges to be visually associated with the corresponding cooling circuits and allow the system to be laid out for easier comprehension. For example, red may be used for the high-pressure side and blue for the low-pressure side.