Faults Displayed With A Fault Code; Faults Displayed Without A Fault Code; Repairs; Checking The Solar Circuit Pump At Output P1 - Viessmann EM-S1 Installation And Service Instructions For Contractors

Faults displayed with a fault code

Meaning of the fault codes
Heat generator installation and service instruc-
tions

Faults displayed without a fault code

Fault
Solar yield too low
Solar circuit pump not running
or runs constantly.
Solar control unit switched off

Repairs

Check the function of the connected components by
means of an actuator test:

Checking the solar circuit pump at output P1

Characteristics of the circulation pump (see the follow-
ing chapter):
Pump always off:
■
– High limit safety cut-out has responded. Reset the
high limit safety cut-out.
– Output P1 faulty
Replace extension.
Solar circuit pump faulty
–
Replace solar circuit pump.
Pump always on:
■
– PWM connection faulty
– Output P1 always live.
Replace extension.
Cause
Temperature sensors inter-
changed.
Air in the solar circuit
Inadequate flow rate
Incorrect circulation
Temperature sensors inter-
changed.
Solar circuit pump faulty or in-
correctly connected
Fuse F1 has responded.
Remedy
Check temperature sensor connections.
Vent the solar circuit. Check flow rate.
Check flow rate.
■
Check connection of output
■
page 19).
Check hydraulic connections.
■
Ensure check valves are operating correctly.
■
Check the system characteristics.
Check temperature sensor connections.
Check solar circuit pump connection (see
page 19).
Carry out an actuator test.
Check fuse F1. See page 19.
Disconnect consumers. Connect again in se-
quence. While doing so, observe the behaviour
of fuse F1.
Heat generator installation and service instruc-
tions
Variable speed circulation pump with PWM control
Whenever a demand is present, a voltage of 230 V
must always be applied to output P1. The pump speed
is governed by means of a control signal via PWM
connection.
If the PWM connection is interrupted, the circulation
pump must be switched off. If the circulation pump
runs at maximum speed when the PWM connection is
interrupted, an incorrect circulation pump has been
installed.
Troubleshooting
(see
sF
∼
15