Vaillant miniVED VED H 3/3, Operating Instructions Manual

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Installation and maintenance instructions 0020323584_00
Appendix
A Troubleshooting
Fault Possible cause Troubleshooting
Despite the water
tap at the draw-
off point being
fully opened, the
product does not
start. The flow regulator in the
water tap at the draw-off
point is calcified or dirty. Clean and/or descale the flow regulator or, if
required, replace it.
The filter at the product's
cold water connection is
clogged. Lock the cold water inlet and then clean the
filter.
The heating system is
defective. Check the resistance of the heating system and,
if required, replace the product.
The safety pressure lim-
iter has triggered. Eliminate the cause of the fault.
Disconnect the product from the power supply.
Depressurise the water pipe by opening the
water tap at the draw-off point.
Unlock the safety pressure limiter.
B Wiring diagram
p >
Q >
L
N
L N
VED H 3/3
p > Q >
L
N
L N
VED H 4/3
VED H 6/3
2 1 3 2 1 3
1 Heating element
2 Differential pressure switch
3 Safety pressure limiter
C Inspection and maintenance work
–
Overview
Maintenance work
Check that the product functions correctly
Descale the product
Clean the water filter in the cold water connector
Cleaning the water tap's flow regulator at the draw-off point