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Pressure Alarms

Pressure Alarm System

MODEL 9502, 9503

Model 8520


The Pressure Alarm System is designed to be used with Thermco gas mixers to indicate low inlet gas pressure. The Pressure Alarm System may also be used for other pressure monitoring applications.

When applied to smaller gas mixers, the Pressure Alarm System is normally mounted on the wall next to the gas mixer. For larger floor mounted gas mixing systems, the Pressure Alarm System may be mounted on the gas mixer.


If the inlet pressure drops below the alarm value, the pressure switch in the Pressure Alarm System will trip, lighting the specific indicator light and sounding the horn. The horn silence button may be pushed to silence the horn. When the inlet pressure returns to normal, the alarm lights and horn will automatically reset.

Oxygen Service

Parts wetted by oxygen are compatible with oxygen and cleaned for oxygen service.


Model Description
9502 2 gas alarm
9503 3 gas alarm

Alarm Setpoint Range:

20-120 PSIG (1.4-8.3 barg)

The 20-120 PSIG alarm setpoint range is standard. Higher alarm setpoint ranges are available on special order. Maximum inlet pressure is 250 PSIG (17.2 barg) for standard design.

Ambient and Supply Gas Operating Temperatures:

2˚F to 122˚F (-17˚C to 50˚C)

Pressure Connections:

1/8” female NPT

Power Requirements:

115 VAC, 50/60 Hz. 0.5 amp. Available on request, 220 VAC, 50/60 Hz, 0.25 amp.


Long life LED


Painted steel enclosure, lockable


9.4 lbs. (4.3 kg)


11.5” (29.2 cm) height, 10.5” (26.7 cm) width, 5.0” (12.7 cm) depth


Not suitable for flammable or corrosive gases; or for medical applications or services associated with life support.

Ordering Information

Thermco products are available through many local industrial gas suppliers. They may also be ordered directly from the factory. To get a quote, click here. It is specially important to order the correct pressure conditions for the application. If there are questions, please contact the Thermco sales engineer.