User Manual

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Building Technologies Division CC1N7491en
18.07.2018
Warning notes
To avoid injury to persons, damage to property or the environment, the following
warning notes must be observed!
Do not open, interfere with or modify the unit!
Siemens AG does not assume responsibility for damage resulting from
unauthorized interference!
∂ All activities (mounting, installation and service work, etc.) must be performed by
qualified staff
∂ Before making any wiring changes in the connection area, completely isolate the
plant from mains supply (all-polar disconnection). Ensure that the plant cannot be
inadvertently switched on again and that it is indeed dead. If not disconnected,
there is a risk of electric shock hazard
∂ Protection against electric shock hazard on the LMU34 and on all connected
electrical components must be ensured through adequate mounting
∂ The following hazards must be considered and eliminated by fitting appropriate
covers and by using adequate constructions:
- Electrical shock hazard
- Injury when handling the unit
- Excessive heat spreading to cables, plastic parts or subassemblies
∂ Before performing any wiring changes, completely isolate the unit from mains
supply and take measures to ensure that the plant cannot be inadvertently
switched on
∂ Use a multipolar switch to isolate the LMU34 from mains supply
∂ Each time work has been carried out (mounting, installation and service work, etc.),
check to ensure that wiring is in an orderly state and that parameters have been
correctly set and make the safety checks as described in «Commissioning notes».
∂ Touch the LMU34 only on the transformer to prevent damage to electronic
components due to static charges
∂ Check the required DHW temperature to prevent scalding. The installer is
responsible for fitting appropriate warning signs near the taps
∂ Fall or shock can adversely affect the safety functions. Such units must not be put
into operation, even if they do not exhibit any damage
∂ On the application, ensure that pollution degree 2 will not be exceeded
∂ Ensure that the level of protection against electrical shock hazard will not be
reduced when installing or integrating the gas burner control into the equipment
∂ Screws for securing / mounting the PCB must not be touchable or must be
separated from active parts by double or reinforced isolation
To ensure safe and reliable operation of the unit, the following points must also be
observed:
- Avoid condensation and damp environments!
If such conditions have occurred, make certain the LMU34 is completely dry again
before switching on power!
- Static charges must be avoided since they can damage the electronic components
when touched
Recommendation: Use ESD equipment!