Functional Checks - Vaillant ECOmax VUW 236 EH Instructions For Installation And Servicing

•
Push both buttons under the diag-
nostic display simultaneously.
The flow temperature will now be
displayed.
•
Reset the maximum hot water tem-
perature selector to the required
setting (see Section 5.15).

5.11 Functional checks

5.11.1 Introduction
The boiler display (8, fig. 43) normal-
ly indicates the primary flow tempera-
ture. Whilst this display is showing the
boiler has internally self checked and
is operating normally. However, if
desired, a functional check of the boi-
ler DHW and CH operation may be
carried out using the status mode of
the built in diagnostics.
5.11.2 Functional check of
DHW operation using
built in diagnostics
•
Set the boiler central heating con-
trol to the `Hot Water only' position
•
Enter status mode by pushing the
right hand diagnostic button once,
e.g. with the tip of a ballpoint pen
(1, fig. 43). The display should
now show `S.0'
•
Turn on a hot tap and draw water
at a high rate.
•
The display will now step through
the following codes:
•
S.10 - calling for operation: DHW.
(display duration: 1 sec)
•
S.11 - fan running and proving
(display duration: 4 -5 secs)
•
S.13 - ignition
(display duration: 10 secs max)
•
S.14 - burner operation: DHW
(display for duration of hot water
draw off)
•
Turn the hot water tap off. The bur-
ner should be extinguished and the
display will now step through the
following codes:
•
S.15 - pump and fan overrun
(display duration: 5 secs)
30
fig. 43