26 - EN
5.1 Procedure for opening the unit
1
2
Do not disconnect the power
to the unit yet. The current
setting of the modulating
bypass valve may block
the removal of the heat
exchanger.
Open the semi-transparent visor.
Change the unit to SERVICE MODE.
(INSTALLER SETTINGS > MAIN
BOARD SETTINGS > SERVICE MODE
> SERVICE MODE).
3
4
5
Disconnect the power to the unit when
the display tells you to.
Remove the 3 screws of the front
cover.
Remove the front cover.
5 Maintenance procedures
Follow all maintenance procedures given in
this chapter and in the user manual. If the
maintenance is not performed periodically
the performance of the ventilation system will
ultimately be compromised.
In this chapter you can find a separate subchapter
for each maintenance action which the user should
not perform. In the user manual you will find all
maintenance actions which the user may perform.
You can find the maintenance procedures of the
ancillaries connected to the unit in their relevant
manuals. You can get a copy of a Zehnder manual
from Zehnder.
If it is necessary to replace a part you can order a
service part from Zehnder. In the chapter about the
service parts you can see which special service sets
are available.
Always disconnect the power supply
of the unit before you start working
on the ventilation system. The unit
can cause personal injury when it
is open while running. Make sure
the unit cannot switch back on by
accident.
Always take ESD-inhibiting measures when
dealing with electronics, such as wearing an
antistatic wristband. The electronics can get
damaged by static charges.
Zehnder recommend that you employ a specialised
cleaning firm to clean the whole ventilation system.
