Mini Merlin Installation, Operation & Maintenance
Rev: 01 02-22
9
PILOT WATER HEATER & BOILER LIMIT BREAKER
The device can be used to directly shut the pilot of a water heater in an alarm or power failure state using a product
from Field Controls. The BMS terminals may also be used to connect to a home alarm system.
REMOTE SHUT OFF
Your mini-merlin can be integrated with remote devices with an open /close circuit
via the Remote Shut-Off volt free switch terminal. This terminal has a factory fitted
link installed. This terminal is normally closed and will alarm when energised open -
isolating the gas supply.
When using this input, only the mains utility output shall de-energize. If you are using the CO or NG relay to shut down
a boilers external limit circuit, you will need to wire the input in series with the relay output.
Auto Reset & Buzzer Switches
ON
OFF
A
u
to
R
es
et
In the event of a power loss
–
the mini-merlin will restart
automatically when power is restored.
In the event of a power loss
–
the mini-merlin will need to
be reset manually when power is restored.
This is the factory default condition.
B
u
zz
er
The buzzer will sound every 15 seconds during pre-alarm
and continuously at alarm level.
This is the factory default condition.
The buzzer will not sound at any gas level.
Building Management System
This device can be integrated with a Building Management System (BMS), a home alarm system, or be used as part
of a boiler low voltage safety limit to make or break a circuit on both gases separately, (valve open or valve closed)
depending on the system.
These switches can be used for a variety of purposes including triggering alarm contacts, operating and external relay
for multiple appliance shutdown and generating status signals for a BMS system.
