Dunkirk Helix VLT Vertical Laser Tube, Wall Hung Modulating Condensing Boiler - Manual (Page 52)

52
13 - TROUBLE SHOOTING
Error shows when safet
y circuit is
open. R
emo
ve J13 connector from
control module. Check for continuit
y
between two pins connected to two pink wires, is continuit
y a
vailable?
YES
NO
Replace Control Module
Boiler fired without enough w
ater flow
through heat ex
changer
. Heat ex
changer
is o
ver heated. Either high limit or heat
ex
changer temper
ature switch is open.
Check the following:
•
Air in system?
•
Verify water flow in system piping
•
Flush system if water is dirty.
Is boiler supply pipe (abo
ve
heat ex
changer) hot? W
ait for boiler to cool down.
YES
NO
Replace Brok
en S
witch
Unplug molex connector on supply temper
ature sensor
. Check continuit
y
between two pins on sensor (two pins
connected
to
two
pink
wires)
.
Is continuit
y a
vailable?
YES
NO
Check for loose connections on two pink wires on J13 connector
, supply sensor
, and
safet
y temper
ature switch.
YES
NO
Fix Loose Connections
Replace Wire Harness
Let all z
ones
run until w
ater
temper
ature
drops.
Is Heat Ex
changer surface hot?
YES
NO
Check high limit
and surface temper
ature
switches