User Manual

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Building Technologies CC1N7491.1en
03.04.2018
Application notes
Notes on integrating the LMU34 (boiler for gaseous fuels type C, rated capacity ′70
kW):
∂ The impact of continuous control of the ignition equipment caused by an internal
failure of one of the burner control components in connection with an earth fault of
one of the connecting wires of the ignition equipment must be assessed depending
on the application
∂ High limit thermostat function
Signals from the potential-free contact at terminals X401: X401 pin 3 / X401 pin 4
will be further handled by the LMU34 in a safety-related manner. Functions ”Shut-
down”, “Lockout” and “Reset” are implemented in the LMU34 and are in compli-
ance with EN 298 and DIN V ENV 14459 (class C)
∂ Signals from the flue gas limiter (thermo fuse) fed to terminals X401: X401 pin 1 /
X401 pin 2 will be further handled in a non-safety-related manner (class A)
The LMU34 conforms to standard for gas boiler type C so DIN EN 483: 2000 (gas boil-
er for central heating).
The LMU34.3 conforms to CSA / ANSI Z21.20b 2001 < 117 kW.
Β
Note!
Prepurge, postpurge and interpurge times including all fan-related parameters
(speed, PWM) are non-safety-related.
The boiler must meet the requirements of 6.4.5 (according to EN 483:2000) through
other means (e.g. by a gas valve which must meet special requirements)
Mounting notes
∂ The electrical wiring inside the boiler must conform to country-specific and local
regulations. The rated loads and the rating of the unit fuse must be taken into ac-
count
∂ Ensure that the relevant national safety regulations are complied with
∂ Make certain that spliced individual wires cannot get into contact with neighboring
terminals
∂ Electromagnetic emissions must be checked on an application-specific basis
∂ The unit must be mounted within a closed housing
∂ When mounted inside the boiler, the maximum permissible ambient temperature
must not be exceeded
∂ On the boiler itself, the device must be installed inside a housing with a minimum
degree of protection of IP40 (DIN EN 60529) – or a minimum of IP54 for outdoor
use)
∂ Resistor R118 can reach high temperatures in operation. This must be considered
when mounting and servicing the PCB