Ariston microSYSTEM 10 RFFI User guide

Servicing
Instructions
Type C Boilers
G.C.N: 41-116-04
LEAVE THESE INSTRUCTIONS
WITH THE END-USER
Country of destination: GB

2
1. SERVICING INSTRUCTIONS
1.1 REPLACEMENT OF PARTS
1.2 TOGAIN GENERAL ACCESS
- Removing the front panel
- Removing the sealed chamber front cover
- Removing the side panels
1.3 ACCESS TO THE COMBUSTION CHAMBER
- Removing the combustion cover
- Removing the burner and jets
- Removing the electrodes
- Removing the main heat exchanger
- Removing the air pressure switch
- Removing the fan
1.4 SERVICING AND REMOVAL OF THE GAS VALVE
- Setting the gas pressures
- Removing the spark generator
- Removing the gas valve
1.5 ACCESS TO THE WATER CIRCUIT
- Removing the pump pressure switch
- Removing the safety valve
- Removing the automatic air vent
- Removing the pump
- Removing the pressure gauge
- Removing the expansion vessel
- Removing the overheat thermostat
- Removing the frost thermostat
- Removing the regulation thermostat
1.6 ACCESS TO THE CONTROL SYSTEM
- Checking the fuses
- Removing the P.C.B.s
2. FAULT FINDING
2.1 FAULT FINDING GUIDE (FLOW-CHARTS)
3. ELECTRICAL DIAGRAMS
4. SHORT SPARE PARTS LIST
TABLE OF CONTENTS

2. The control panel moves downward and when pulled forward,
rotates on two lateral hinges; the panel stays in a semi-
horizontal position, which allows access to the inner parts of
the boiler (FIG. 1.2);
3. In order to increase the manouvering space, it is possible to
raise the control panel and rotate it to a fully horizontal position
(FIG. 1.3);
4. Remove the screws “B” from the front panel bottom lip
(FIG. 1.4);
5. Lift the front panel up and forward from the raised screws at the
the top of the casing (FIG. 1.5).
FIG. 1.4
B
FIG. 1.5
3
1. SERVICING INSTRUCTIONS
The life of individual components varies and they will need
servicing or replacing as and when faults develop.
The fault finding sequence chart in chapter 2 will help to locate
which component is the cause of any malfunction, and instructions
for removal, inspection and replacement of the individual parts are
given in the following pages.
1.1 REPLACEMENT OF PARTS
1.2 TOGAIN GENERAL ACCESS
All testing and maintenance operations on the boiler require the
control panel to be lowered. This will also require the removal of
the casing.
1.2.1 Removing the front panel
1. Loosen the fastening screws“A”of the control panel located on
the lower part of the panel itself. (FIG. 1.1);
A
FIG. 1.3
FIG. 1.1
FIG. 1.2
To ensure efficient safe operation, it is recommended that the
boiler is serviced annually by a competent person.
Before starting any servicing work, ensure both the gas and
electrical supplies to the boiler are isolated and the boiler is
cool.
Before and after servicing, a combustion analysis should be made
via the flue sampling point (please refer to the Installation Manual
for further details).
After servicing, preliminary electrical system checks must be
carried out to ensure electrical safety (i.e.polarity, earth continuity,
resistance to earth and short circuit).

4
1.2.2 Removing the sealed chamber front cover
1. Remove the screws “C” (FIG. 1.6);
2. Lift the sealed chamber front cover from the locating pins
(FIG. 1.7).
FIG. 1.6
C
C
FIG. 1.7
1.2.3 Removing the side panels
1. Remove the four screws “D” for each side panel (FIG.1.8);
2. Pull the panel away from the boiler at the base, then lift the
panel up and remove from the boiler.
D
D
D
FIG. 1.8

1.3.3 Removing the electrodes
Before carrying out this procedure, unscrew and slide the
burner forward (see previous section).
1. Remove rubber gasket “G” (FIG. 1.12);
2. To remove the detection electrode disconnect the cable
at its connection point close to the P.C.B. (FIG. 1.13);
FIG. 1.12
G
FIG. 1.13
1.3.2 Removing the burner and jets
1. Remove the screws “F” from the burner (FIG. 1.10);
2. Remove the burner (FIG. 1.11);
3. Disconnect the electrodes (see section 1.3.3);
4. Remove the jets using a No. 7 socket spanner;
5. Replace in reverse order.
5
1.3.1 Removing the combustion cover
1. Remove the screws “E” (FIG. 1.9);
2. Lift off the combustion cover.
1.3 ACCESS TO THE COMBUSTION CHAMBER
E
E
E
FIG. 1.9
FIG. 1.10
Fig. 1.11
F
F

6
3. Remove screw “H” (FIG. 1.14);
4. Gently slide the electrode downward (FIG. 1.15).
To replace, repeat the steps in reverse order, paying
particular attention to the following:
a-Centre the electrode in the positioning hole carefully,
otherwise the electrode may break;
b-Ensure that the left hand and right hand electrodes are
located the correct way round (facing each other), to
give the correct spark gap;
c-Check that the cables have been connected correctly;
d-Check that the rubber gasket covers the cable/ electrode
connection point completely.
FIG. 1.14
FIG. 1.15
H
1. Drain the boiler of water;
2. Release the overheat thermostat sensor “I” (FIG. 1.16);
3. Release the two connection nuts “J” connecting the
exchanger to the flow and return pipes (FIG. 1.17);
4. Remove the heat exchanger by sliding forward (FIG.
1.18).
1.3.4 Removing the main heat exchanger
FIG. 1.17
J
Fig. 1.16
I
FIG.1.18

1. Disconnect electrical connections “N”and silicon pipe “O”
(FIG.1.22);
2. Remove screw “P” and remove the fan collar clamp “Q”
(FIG.1.23);
3. Remove screws “R” (FIG.1.24);
4. Remove fan and mounting plate (FIG.1.25).
1.3.6 Removing the fan
1. Disconnect the electrical connections “K” and silicone
pipes “L” from their connection points (FIG. 1.19);
2. Remove screws “M” on the top of the sealed chamber
(FIG. 1.20);
3. Lift out the air pressure switch (FIG. 1.21);
4. Unscrew to remove the switch from the plate.
FIG. 1.20
FIG. 1.19
7
1.3.5 Removing the air pressure switch
L
L
K
M
M
FIG. 1.21
FIG. 1.24
R
FIG. 1.23
P
Q
FIG. 1.22
N
O
FIG. 1.25

8
1.4 SERVICING AND REMOVAL
OF THE GAS VALVE
1.4.1 Setting the gas pressures
1
2
3
A
B
C
F
D
Setting the maximum power of the boiler
1. Check that the supply pressure to the gas valve is a minimum of 20 mbar
for natural gas.Turn off the gas supply at the isolation point under the
boiler
2. To do this, slacken the screw “A”.
Fit the pipe of the pressure gauge to the inlet pressure test point of the gas
valve “B”.
Turn on the gas supply at the isolation point under the boiler and with
the boiler running, read the inlet working pressure on the gauge.
When you have completed this operation, turn off the gas supply at the
isolation point under the boiler, remove the pressure gauge and tighten
the screw “A” securely into its housing to seal off the gas.Turn on the gas
supply at the isolation point under the boiler and test the screw for
gas escaping with an approved soap and water solution.
3. To check the pressure supplied by the gas valve to the burner, with the
boiler turned off, slacken the screw “C”.Fit the pipe of the pressure gauge
to the outlet pressure test point of the gas valve “D”.
Disconnect the compensation pipe “E”either from the gas valve or from
the sealed chamber.
4. Push the On/Off button to “ON” position -green light- and push the Heating
button to “ON” position -green light-
Turn on the boiler by setting the external controls.
Adjust the 10mm nut “F” to set the gas pressure Turn the nut clockwise to
increase and anti clockwise to decrease the pressure until the required
pressure is achieved (see TABLE Apage 9)
5. When you have completed the above operations, turn off the external
controls, re-connect the supply terminal to the modureg on the gas valve
and replace the cap on the screw of the modureg.
Setting pressure for soft ignition.
The soft light pressure is factory set.
If the ignition is not regular (e.g: not complete burner ignition or ignition
noise) check the soft light regulator position.
The soft light pressure will need adjusting as follows:
- Turn off electrical supply;
- referring to picture 4, open the dust cap of the soft light regulator, by
unscrewing in clockwise direction the white screw;
- turn the adjustment screw one step in the direction max to increase or in
the direction min to decrease the soft light pressure;
- after each adjustment of the regulator, turn on the electrical supply and
recheck burner ignition (wait 20 seconds between each cycle to allow
the gas valves’ internal servo system to reset).When the required level
is achieved, close the dust cap.
VG003Aa
VG003Ab
VG003Ac
E
VG002Ab
4

9
1.22
20
8.3
2.9 2.9
----
-----
-----
0.91 Kg/h
------ Kg/h
22.9 mbar
---- mbar
28 mbar
0.90 Kg/h
------ Kg/h
29.5 mbar
---- mbar
37 mbar
6 x 1.30 6 x 0.77
6 x 0.77
Gas restrictor ¿
10 RFFI
TABLE A
TB016A
6. Remove the pipe from the pressure gauge and connect screw “C”to the
pressure outlet in order to seal off the gas.
7. Carefully check the pressure outlets for gas leaks (valve inlet and outlet).
IMPORTANT!
Whenever you disassemble and reassemble the gas connections, always
check for leaks using an approved soap and water solution.

10
FIG. 1.28
FIG. 1.29
U
V
V
1.4.3 Removing the gas valve
Important! Before removing the gas valve, ensure the gas
supply is turned off.
1. Disconnect all the cables from the solenoid and
modureg;
2. Remove the spark generator (see previous section);
3. Release the top nut “U”(FIG. 1.28);
4. Remove the screws “V”from the bottom of the gas valve
pipe (FIG. 1.29);
5. Remove the gas valve).
1.4.2 Removing the spark generator
1. Disconnect ignition leads “S”by pulling upward
(FIG. 1.26);
2. Remove the screw “T”(FIG. 1.27);
3. Remove the spark generator by pulling forward from the
gas valve.
FIG. 1.27
FIG. 1.26
S
T

11
1. 5. 2 Removing the safety valve
1. Loosen nut “Y”(FIG. 1.33);
2. Disconnect the discharge pipe work from below the
boiler;
3. Unscrew and remove the valve.
1.5.3 Removing the automatic air vent
1. Unscrew valve top “Z”(FIG. 1.34);
2. Remove valve complete with float (FIG 1.35).
FIG. 1.33
FIG. 1.34
Y
Z
FIG. 1.35
Important! Before any component is removed, the boiler
must be drained of all water.
1.5 ACCESS TO THE WATER CIRCUIT
FIG. 1.31
W
FIG. 1.32
X
1.5.1 Removing the pump pressure switch
1. Remove the cable of the pump pressure switch “W”
(Fig. 1.31);
2. Unscrew the pump pressure switch by using a spanner
on the nut “X”(FIG. 1.32);
3. Remove the pump pressure switch.

12
1.5.4 Removing the pump
1. Remove the U-clips “A1”and “B1”(FIG. 1.36);
2. Remove the retaining clip “C1”(FIG. 1.37);
3. Release the nut “D1”(FIG. 1.38);
4. Remove the pipe “E1”(FIG. 1.39);
5. Remove the screw “F1”(FIG. 1.40);
6. Remove the pump (FIG. 1.41).
FIG.1.37
FIG.1.36
FIG.1.38
C1
A1
B1
FIG. 1.39
FIG. 1.40
FIG. 1.41
D1
E1
F1

13
1.5.6 Removing the expansion vessel
1. Release nuts “H1”and remove the gas pipe (FIG. 1.44);
2. Release nut “I1”(FIG. 1.45);
3. Remove lock-nut “J1”(FIG. 1.46);
4. Remove the expansion vessel (FIG. 1.47).
1.5.5 Removing the pressure gauge
1. Remove the U-clip “G1”and remove the pressure gauge
coupling (FIG. 1.42);
2. Push the pressure gauge through the control panel from
the rear (FIG. 1.43).
FIG. 1.42 FIG. 1.44
G1
FIG. 1.43
H1
I1
FIG. 1.45
FIG. 1.46
FIG. 1.47
H1
J1

14
1.5.6 Removing the overheat thermostat
1. Disconnect the overheat thermostat electrical
connections “K1”(FIG. 1.48);
2. Then remove the thermostat from its mounting by
releasing the securing clip (FIG. 1.49).
1.5.7 Removing the frost thermostat
1. Disconnect the frost thermostat electrical connection
“L1”(FIG. 1.50);
2. Then remove the thermostat from its mounting by
releasing the securing clip (FIG. 1.51).
1.5.8 Removing the regulation thermostat
1. Remove the regulation thermostat sensor from its
mounting by releasing the securing clip “M1”(FIG. 1.52);
2. Separate the facia panel from the rear of the control
panel (see section 1.6.2);
3. Remove the electrical connections “N1 from the
regulation thermostat (FIG. 1.53);
4. Pull the regulation knob from the spindle of the
thermostat;
5. Remove the thermostat from the control panel facia by
unscrewing the mounting screws.
FIG. 1.48
FIG. 1.49
K1
FIG. 1.52
FIG. 1.51
M1
L1
FIG. 1.50 FIG. 1.53
N1

15
1.6.2 Removing the P.C.B.s
1. Isolate electricity;
2. Remove the screws “O1”(FIG. 1.56);
3. Separate the facia panel from the rear of the control
panel;
4. Unplug all electrical connections from the P.C.B. and
remove the screws “P1”and remove the P.C.B. (FIG.
1.57).
FIG. 1.56
O1
O1 O1
O1 O1
P1
P1
P1
P1
O1
FIG. 1.57
1.6.1 Checking the fuse
1. Remove the inspection cover on the reverse of the
control panel (FIG. 1.54);
2. Remove the fuse mounted on the reverse of the
inspection cover (FIG. 1.55).
1.6 ACCESS TO THE CONTROL SYSTEM
FIG. 1.54
FIG. 1.55
Important! Isolate the electrical supply to the boiler before
accessing the control panel.

16 B063
2. FAULT FINDING
P RELIMINARY CHECKS
MAKE SURE THAT
:
IS
THE SUPPLY
L.E.D. ILLUMINATED?
IS
THE L.E.D.
ILLUMINATED?
NO
NO
NO
YES
NO
1 - CHECK THE FUSES
2 - CHECK THERE IS POWER
SUPPLIED TO THE P.C.B.S
3 - CHECK/REPLACE THE P.C.B.
(CT1)
1 - CHECK THE INTEGRITY
OF THE L.E.D.
2-C
HECK/REPLACE THE P.C.B.
(CT1)
PRESS THE
ON/OFF BUTTON
PRESS THE CENTRAL
HEATING BUTTON
FROST
PROTECTION IS
ACTIVATED <5¡C. ISTHE
FROSTPROTECTION
REQUESTED?
IS
TIME CLOCK/
PROGRAMMER
AND/OR ROOM
CALLING FOR
HEATING?
THE
THERMOSTAT
A
1 - THERE IS SUFFICIENT
WATER IN THE SYSTEM
2 - THE GAS IS TURNED ON
3 - THE ELECTRICAL SUPPLY
IS TURNED ON
YES
YES
YES
It is possible to detect and correct any defect by using the standard fault
finding diagrams described in this chapter.
2.1 FAULT FINDING GUIDE
(FLOW-CHARTS)
FC002Aa

17
B063
ISTHE PUMP
RUNNING?
NO
YES
POWER TO
THE PUMP?
1 - CHECK THE OPERATION
OF THE PUMP
2 - RELEASE/REPLACE THE
PUMP
1 - CHECK THE PUMP CABLE
2-CHECK/REPLACE P.C.B.
(CT1)
3 - CHECK THE SYSTEM
PRESSURE GAUGE IS AT
1.5 BAR
A
ISTHE FAN
RUNNING?
BOILER
SHUTDOWN?
POWER TO
THE FAN?
NO
YES
YES
NO
YES
NO
NO
YES
1 - CHECK/REPLACE AIR
PRESSURE SWITCH
AND CABLE
2 - CHECK IF THE RESET
DETECTION ELECTRODE
IS JAMMED
3 - CHECK/REPLACE
1 - CHECK/REPLACE FAN
CONNECTION CABLE
2 - CHECK/REPLACE P.C.B.
3 - CHECK/REPLACE AIR
PRESSURE SWITCH
1 - REPLACE THE FAN
1 - RESET THE BOILER
INTERNAL
P.C.B. PROTECTION
ACTIVATED?
B
NO
YES
FC002Ab

18 B063
ISTHE BURNER
ALIGHT?
YES
NO
YES
YES
BOILER
WORKING?
YES
NO
NO
NO
NO
YES
5-CHECK/REPLACE P.C.B. (CBM2)
4-C
HECK/REPLACE P.C.B. (CBM2)
4 - CHECK/REPLACE
P.C.B. (CBM2)
1 - CHECK/REPLACE IGNITION
ELECTRODES
2 - CHECK THE CABLES
3 - CHECK SPARK GENERATOR
4 - CHECK IGNITION ELECTRODE
CABLES
1 - CHECK POWER SUPPLY TO
THE GAS VALVE
2 - CHECK OPERATION OF THE
GAS VALVE
3 - REPLACE THE GAS VALVE
1 - CHECK IF THE FLAME
ELECTRODE
2 - CHECK THE SOFT-LIGHT
GAS PRESSURE
3 - CHECK/REPLACE DETECTION
ELECTRODE
STRIKES THE DETECTION
PRESS THE RESET
BUTTON
ISTHE
AIR PRESSURE SWITCH
ACTIVATED?
CHECK
P ON PRESSURE
TEST POINT
DOES
THE SPARK
SEQUENCE
START?
HASTHE
BOILER SAFETY
SHUTDOWN BEEN
ACTIVATED?
1 - CHECK EXHAUST DISCHARGE
2 - CHECK VENTURI AND TUBES
3 - CHECK THE FAN EFFICIENCY
4 - REPLACE FAN
1 - CHECK AIR PRESSURE
SWITCH CABLE
2 - CHECK/REPLACE AIR
PRESSURE SWITCH
3 - CHECK/REPLACE P.C.B.
(CBM2)
B
P mbar0.5
P 0.5 mbar
∆
IS
THERE STILL
A PROBLEM?
NORMAL
OPERATION
NORMAL
OPERATION
NO YES
FAULT LIST POSSIBLE CAUSES
1
2
3
4
5
NOISEY OPERATION
NOISEY OPERATION
DECREASE/INCREASE OF HEATING CIRCUIT
PRESSURE
DECREASE/INCREASE OF HEATING CIRCUIT
PRESSURE
REPEATED SHUTDOWNS
REPEATED SHUTDOWNS
REPEATED OPERATION OF SAFETY THERMOSTAT
REPEATED OPERATION OF SAFETY THERMOSTAT
INSUFFICIENT RADIATOR TEMPERATURE
INSUFFICIENT RADIATOR TEMPERATURE
- MAIN HEAT EXCHANGER FAULTY OR BLOCKED
WITH LIME-SCALE DEPOSITS
- LOW HEATING SYSTEM WATER PRESSURE
- CHECK GAS PRESSURES
- CHECK HEATING THERMOSTAT
- CHECK FAN
- CHECK PUMP
- MAIN HEAT EXCHANGER FAULTY OR BLOCKED
WITH LIME-SCALE DEPOSITS
- LOW HEATING SYSTEM WATER PRESSURE
- CHECK GAS PRESSURES
- CHECK HEATING THERMOSTAT
- CHECK FAN
- CHECK PUMP
- CHECK FOR LEAKS ON THE HEATING CIRCUIT
- FAULTY FILLING LOOP
- FAULTY EXPANSION VESSEL
- CHECK FOR LEAKS ON THE HEATING CIRCUIT
- FAULTY FILLING LOOP
- FAULTY EXPANSION VESSEL
- FAULTY DETECTION ELECTRODES
- CHECK GAS PRESSURES
- CHECK FLAME DETECTION ELECTRICAL CIRCUIT
- FAULTY DETECTION ELECTRODES
- CHECK GAS PRESSURES
- CHECK FLAME DETECTION ELECTRICAL CIRCUIT
- FAULTY HEATING THERMOSTAT
- FAULTY OVERHEAT THERMOSTAT
- PRESENCE OF AIR IN THE HEATING CIRCUIT
- CHECK BURNER PRESSURES
- CHECK EXCHANGER FLUEWAY
- FAULTY HEATING THERMOSTAT
- FAULTY OVERHEAT THERMOSTAT
- PRESENCE OF AIR IN THE HEATING CIRCUIT
- CHECK BURNER PRESSURES
- CHECK EXCHANGER FLUEWAY
- CHECK HEATING THERMOSTAT
- CHECK BY-PASS
- CHECK GAS PRESSURE
- CHECK HEATING THERMOSTAT
- CHECK BY-PASS
- CHECK GAS PRESSURE
∆
≤
∆
FC002Ac

19
B063
3. ELECTRICAL
DIAGRAMS
SE011A
LEGEND:
A - On/Off Switch
B - On/Off L.E.D.
C - Heating Switch
D - Heating L.E.D.
E - Reset Button
F - Ignition Failure (Lockout) L.E.D.
A01 - Pump Pressure Switch
A02 - Frost Thermostat
A03 - Modulator
A04 - Circulation Pump
A05 - Regulation Thermostat
A06 - External Control System
A07 - Time Clock Connector
A08 - External (Room) Thermostat
A09 - Air Pressure Switch
A10 - Fan
A11 - Overheat Thermostat
A12 - Spark Generator/Gas Valve Supply
A13 - Detection Electrode
Colours:
Wh -White
Bl -Blue
Gry -Grey
Brn -Brown
Blk -Black
Rd -Red
Grn/Yll-Yellow/Green

20 B063
SF008A