Repairs; Check Solar Circuit Pump At Output Sf; Check Connection At Output Ss - Viessmann SM1 Installation And Service Instructions Manual

Troubleshooting
Errors without fault code display
Fault
Solar circuit pump not running
or runs constantly
Output not switched or per-
sS
manently switched
Solar control unit switched off

Repairs

Check function of connected components by means of
a relay test (actuator test).
Check solar circuit pump at output
Characteristics of the circulation pump (see also the
following chapter):
Pump always off:
■
– High limit safety cut-out has responded. Reset the
high limit safety cut-out.
– Output faulty
sF
Replace solar control module.
Solar circuit pump faulty
–
Replace solar circuit pump.
■ Pump always on:
– Coding address 02 incorrectly set
– PWM connection faulty
– Output always 'live'
sF
Replace solar control module.
Multi stage circulation pump
In the case of stepped circulation pumps, the speed
can be changed via wave packet control.
When output is on, a voltage between 100 and
sF
∼
230 V must be present.
Code 02:1 must be set.
Check connection at output
Subject to system scheme, a circulation pump or a
3-way diverter valve can be connected to output
When output sS is on, a voltage of 230 V
present.
14
(cont.)
Cause
Temperature sensors inter-
changed.
Solar circuit pump faulty or in-
correctly connected.
Incorrect function configured.
Solar control unit faulty.
MCB F1 has responded.
sF
present.
Code 02:0 must be set.
Variable speed circulation pump with PWM control
Output
230 V
0 V
Code 02:2 must be set.
A heating circuit pump with PWM control is installed in
case the circulation pump runs at its maximum speed
when the PWM connection has been disconnected.
Heating circuit pumps with PWM control are unsuitable
for use in solar thermal systems.
sS
.
sS
∼
must be
Remedy
Check temperature sensor connection. See the
relevant system example.
Check setting of coding address 20.
Check solar circuit pump connection (see
page 14).
Check setting of coding address 02.
Carry out a relay test.
Check setting of coding address 20.
Check connection of output
Carry out a relay test.
Check fuse F1. See page 23.
Disconnect consumers and reconnect in se-
quence. During this, observe the behaviour of
MCB F1.
Service instructions for the heat source or the
control unit
High efficiency circulation pump or circulation
pump with inherent variable speed control
When output is on, a voltage of 230 V
sF
must indicate a permanent voltage of
sF
∼
. The pump speed is governed by means of a
control signal (0 - 15 V ) via connection PWM.
−
Pump off
−
8 - 15 V Pump runs at its maximum speed
−
If output functions correctly during the relay test but
sS
not in normal operation, check setting of coding
address 20.
(see page 14).
sS
∼
must be