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Analygas® Systems Model 21 is an economical and durable gas monitor.

It has stood the test of time, having been upgraded and improved during a continuous production span of over 30 years, yet it is still

as popular as ever with end users.

The Model 21 protects people, produce and machinery from excessive concentrations

of gases and vapours.

It is particularly suited to operation in unattended locations such as machine

rooms and parking garages. 


Reliable Broad Band Sensors

Visual and Audible Alarms


Optional Digital Display (Front Panel or Remote Mounted)

Output Relays


Simple Calibration

Easy To Install 

Analygas® Systems Model 21 is a wall mounted

gas monitor for use in non-hazardous indoor locations. It has 2 alarm levels and is supplied

with 1 or 2 sensors. Either or both sensors can be configured to activate the alarms. Sensors may be mounted on the unit or in a remote area.

Dry contact relays are included to control

ventilation fans or permit activation of other

auxiliary equipment.

A 4-20mA output is standard for the purpose of

data logging, PLC or computer processing. 


Solid state sensors

Optional Digital Display  

1 or 2 Sensing Points 

120V or 240V Input, 10VA 

4-20mA or 0-1V Output


2 Output Relays 

Operating temperature

-40°C to 40°

-40°F to 104°F

A digital display indicating gas concentration

is available for mounting on the front panel or

at a remote site.

To reduce unnecessary fan cycling, the Model 21 is equipped with electronic timers, which delay the action of the alarms and relays.

This helps prevent excessive wear on external control systems.

This favourite of many years is ideal for use in machine rooms, parking garages, loading docks, battery charging areas, furnace rooms, etc. 

Carbon Monoxide
(consult factory)
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