Preventive Maintenance - Dantherm HEX 70 Service Manual

Preventive maintenance

Introduction
Caution
Cleaning/-
inspection
Trouble shooting
12
Preventive maintenance has to be carried out to keep the heat exchanger fit to meet
specifications. The unit also needs preventive maintenance with specific intervals to
avoid breakdown or inefficient operation and to maximize the unit‟s lifetime.
It is important to notice that intervals between maintenance can vary depending on the
specific environment of the unit.
Parts which need preventive maintenance:
 Heat exchanger
 Fans
 Switch off DC supply before working on the unit
 Make sure that all work has been performed correctly before switching power back
on
The unit must be cleaned according to the recommended preventive maintenance in-
tervals of six months.
Remove front cover to access to the internal and the external fans. The core can be in-
ternally cleaned as well.
Operating errors may occur. Follow the columns from left to right to trouble shoot the
problem at hand.
Problem
The red LED illuminates
constantly
The red LED is flashing
The internal fan runs at
low speed
The external fan runs at
low speed
Cause
Too high temperature in
the enclosure, above
70 °C or fan failure
Onboard sensor has been
disconnected/shorted
Temperature in the enclo-
sure below 20 °C
Temperature in the enclo-
sure below 30 °C
Solution
See if airways are free and
clean. See "Cleaning"
above.
Replace fan if necessary
See if test plug is in place.
Replace controller if nec-
essary
This is due to the control
strategy
This is due to the control
strategy