Buderus 500 - 24/C, Servicing Manual

Page: 23 / 80

Diagnosis 6
We reserve the right to make technical modifications Buderus Ltd. • http://www.buderus-domestic.co.uk
Servicing manual Gas condensing boiler Buderus 500-24/S, 500-24/C and 500-28/C • Issued 02/2006 23
step 20
Is the turbine flow-meter working correctly (along with DHW temperature sensor of any external storage-type
water that might be fitted)? Yes:
→
step
22
No:
→
step
21
step 21
Replace the turbine flow-meter, or DHW temperature sensor of any external storage-type water heater that
might be fitted.
→
box
42
step 22
Check the cable of the turbine flow-meter, see box 112, or cable of the DHW temperature sensor of any
external storage-type water heater that might be fitted.
step 23
Is the cable correctly connected and free of damage? Yes:
→
box
41
No:
→
step
24
step 24
Replace the cable loom (or the affected part thereof).
→
box
42
step 25
Check to ensure that the boiler starts up to supply hot water, see box 15.
step 26
Does the boiler start up? Yes:
→
step
28
No:
→
step
27
step 27
Interpret current display codes box 20 and deal with fault.
→
box
42
step 28
Check to ensure that the tap flow rate is correctly adjusted, see box 180.
step 29
Is the tap flow rate correctly adjusted? Yes:
→
step
31
No:
→
step
30
step 30
Correctly adjust the tap flow rate, see box 180.
step 31
Is an
internal
3-way valve fitted? Yes:
→
step
34
No:
→
step
32
step 32
Check the movement of the servomotor of the Buderus 24V AC external 3-way valve, see box 211.
step 33
Does the servomotor of the Buderus 24V AC external 3-way valve move correctly? Yes:
→
step
36
No:
→
step
63
step 34
Check the movement of the servomotor of the
internal
3-way valve, see box 181..
step 35
Does the servomotor of the
internal
3-way valve move correctly? Yes:
→
step
39
No:
→
step
57
step 36
Check to ensure that the the Buderus 24V AC external 3-way valve has been fitted correctly,
see box 227.
step 37
Has the Buderus 24V AC external 3-way valve been fitted correctly? Yes:
→
step
69
No:
→
step
38
step 38
Fit the Buderus 24V AC external 3-way valve in the correct way, see box 227.
→
box
42
step 39
Check the drive mechanism of the
internal
3-way valve, see box 195.
step 40
Is the drive mechanism of the
internal
3-way valve working correctly? Yes:
→
step
42
No:
→
step
41
step 41
Replace the drive mechanism of the
internal
3-way valve, see box 198.
→
box
42
step 42
Check the circulation for debris, see box 97.
step 43
Is there any debris in the pump? Yes:
→
step
44
No:
→
step
45
step 44
Clean the pump, see box 97.
→
box
42
step 45
The following components must be checked for soiling and/or damage:
- combustion-air inlet pipework
- heat exchanger
- flue-gas pipework.
step 46
Are the above-mentioned components clean and free of damage? Yes:
→
step
48
No:
→
step
47
step 47
Clean and/or replace the corresponding components.
→
box
42
box 22