Installation & Operation Manual Merlin Gas Detector
Rev: 18 03-20
3
INSTALLATION
Planning
Our detectors should be installed in areas at risk of gas leaks e.g. over boilers, valves or meters.
Take in to account the design of the air flow patterns within the zone area.
Detectors should be installed in the correct orientation, as recommended by the manufacturer,
and ease of access should be accounted for to allow for any bump tests, recalibration and
other forms of maintenance.
Areas to avoid
Avoid conditions of any other environmental factors that could potentially impede the
accuracy and operation of the detectors such as; condensation; vibration; temperature,
pressure, the presence of other gases, electromagnetic interference and draft zones.
Area of coverage
Consider the coverage required and function of the area. Emphasis should be placed on
airflow patterns and correct placement, not perceived detecting ranges. The target gas will
only be identified when contact is made with the sensing element itself.
Typical Location and Positioning
Locations for detectors will vary based on the intended application and target gas, they should
be located near identified sources of a potential gas leaks/ pockets where hazardous gas
could quickly accumulate and areas of identified consequential risk.
The composition of the target gas and its density relative to air are used as the basis for the
recommended height of sensors. Generally, the installation height of a sensor for a heavy gas
(such as propane) would be close to the lowest point in the area, and for a light gas (such as
methane) would be close to the highest point in the area.
These recommended heights may vary based on air flow and temperature conditions in
addition to the proposed application and location – this is particularly apparent with oxygen
depletion sensors, and the target gas that they are used for.
Target Gas
Typical Detector Position
Natural Gas/Methane (NG/CH
4
) High Level - 300mm (1ft) from ceiling
Liquid Petroleum Gas (LPG)
Low Level - 300mm (1ft) from ground level
Carbon Monoxide (CO)
Breathing Zone - 1700mm (5ft 6”) from ground level
Hydrogen (H)
High Level - 300mm (1ft) from ceiling
Max number of detectors per zone is 3.
Multiple detectors may be required to adequately protect property and persons.
