Installation, Operation & Maintenance Merlin CO2 TFT
Rev 1 05-21
5
Wiring your CO2-TFT
MAINS POWER/LINE IN
(110-120vac option)
Single-phase mains power is supplied to the [POWER/LINE IN] connector.
LINE & NEUTRAL ONLY.
GAS VALVE INPUT
It is possible for your CO2 TFT to receive a signal from a gas solenoid valve via Live & Neutral terminals on our merlin
panels when wired parallel. To receive a signal you must ensure that you configure the CO2 TFT to Natural or
Mechanical ventilation mode – see settings
for ventilation types.
When gas is supplied/in use – the CO2 TFT
will receive a signal from the gas valve and
display the [GAS IN USE] message. The CO2
TFT will configure itself automatically to
operate in ‘Kitchen’ mode until the gas supply
is turned off – see ‘Settings’ for configuration.
Recommended for teaching areas with gas appliances such as laboratories and food technology rooms.
CO2 ALARM (Not a mains output)
This terminal can also connect to a building management system (BMS) or to a
Merlin panel to send an alarm signal upon alarm levels of CO
2
. This terminal can
also switch the Live (energise/ de-energise) a gas valve upon alarm levels of carbon
dioxide.
CO2 PRE-ALARM
This relay can send a signal to a Building Management System (BMS) or Merlin
panel when CO2 reaches pre-alarm level.
FAN ENABLE
This relay output can be connected to a fan switch which can energise fans via a
signal. This relay will switch on a fan from the current CO
2
level only, by current
temperature only or by the status of both (whichever is greatest) as follows:
N/C:
>600ppm / >23°C (73.4°F) N/O: <550ppm / <22°C (71.6°F)
These levels cannot be altered.
