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4.3
Maintenance and repair by the skilled technician
If regular maintenance work is not carried out on the ComfoAir 70, this will affect the functionality of the user-
friendly ventilation system.
It is vital that an ESD armband be worn during work on the electrical system, in order to protect the control board
from electrostatic effects!
Prior to performing repairs or maintenance on the unit, make sure that the main power supply is disconnected!
Routine maintenance of the Zehnder ComfoAir 70 is easy to carry out and should be performed regularly to keep the unit
operating hygienically and flawlessly. If the air filters are replaced with a factory-recommended model at least every six months,
the maintenance interval is two years for other items. If the unit is operated improperly or with low-quality filters, the enthalpy
exchanger must be cleaned immediately, before continued operation.
As part of the maintenance for the unit, the exterior wall hood and the intake passage for the outdoor air must be regularly checked
for debris and blockage. Any possible debris occurring must be removed immediately. The removal and installation of the exterior
wall hood is described in 4.2.7.
4.3.1
Inspection and cleaning of enthalpy exchanger
In doing so, proceed as follows:
1. Disconnect the ComfoAir 70 from the power supply voltage.
2. Remove the upper canopy by sliding up. Undo the right fastening screw for the lower canopy, and pivot it to the left.
3. Pull the unit carefully out of the wall mounting pipe (available separately) (available separately) until the back side of the upper
EPP housing is in front of the top edge of the wall bracket.
If a sensor system module is installed, then the sensor cable must be disconnected at the SENSOR X8 terminal
point on the control board, and withdrawn from the recess in the lower EPP housing!
To do so, the plug on the ribbon cable must be removed from the control panel, and the lower canopy unscrewed.
After that, the unit can be pulled out enough to have free access to the control board.
INSTRUCTIONS FOR SKILLED INSTALLERS
