Honeywell DTC 100/2 User Manual Instructions For Installation And Maintenance page 12

DTC 100/2
Most frequently occuring failures
PROBLEM
No matter what the
temperature is, the
pump never operates
No matter what the
temperature is, the
pump keeps operating
Temperature limits do
not work
Despite the warmness
of the collectors, the
sanitary water is cool
or not warm enough
12
POSSIBLE FAILURE
- there is no mains voltage
- the switch is in 0-position
- short-circuited DHWS sensor
- short-circuited collector
sensor
- the switch in position 1
- disconnected collector sensor
- short-circuited DHWS sensor
- the motor actuated ball valve
remains open, the closing flap
stays open (termal circulation
of water is possible)
- the setting of T2 is too low
- the difference is set too high
ELIMINATION
- check the mains voltage
- put the switch into AUTO
position
- check the sensors
- put the switch into
position AUTO
- check the sensors
- check the machine
installation
- check the settings