QUICK REFERENCE
6.2
NORMAL OPERATION
The C36 Combi and C36P Combi boilers feature
a user display which shows actual flow
temperature at all times when not serving a DHW
demand. If a DHW demand is detected the boiler
display changes to show the actual DHW
temperature. However, the display can also be
used to show other information about the
operation of the boiler. By pressing the “Installer”
button once the display changes to show the
number 1. Each time the “Installer” button is
pressed the number increases up to a maximum
of 7. Having select the required number in this
way the display, if not touched for a further 5 seconds the display changes again to show the value
relative to that number. The table below shows the values associated with each number
INSTALLER INFORMATION NUMBERS
DHW Flow rate. Divide this number by 6 to read the actual DHW flow rate through
the boiler in litres per minute.
8
Actual flue temperature (of the flue temperature reaches 80C the boiler will drop to
minimum rate until the flue temperature drops to 70C. If the flue temperature
reaches 90C the boiler will shutdown.)
7
Software version of boiler (not relevant to normal fault diagnosis)
6
System water pressure, in bar. (Maximum 2.5 bar, minimum 0.6 bar. The boiler will
shut down if the water pressure drops below 0.5 bar)
5
Actual DHW temperature (maximum 69C)
4
Actual CH return temperature (maximum 72C) (NB Flow temperatures more than
20C above return temperature may lead to overheat and noise problems. Check
the pump performance and the system for blockages)
3
Actual CH flow temperature (maximum 84C)
2
The flame current (in micro amps) detected from the burner (should be <2 when off
and >5 when burner on. Low flame current readings suggest poor combustion and
may lead to flame lockouts. Check gas supply, air supply and combustion setting.)
1
Meaning
Display
You can return to the normal display mode at any time by pressing the “Reset” button once.
During normal operation the green lamps beside the CH +/- buttons and DHW +/- buttons indicate
the mode of operation. If the lamp is not lit then no demand for that function (ie CH or DHW) is
present. In CH mode a demand is received by a 230V signal to SL or via the Keston Room Control
unit. In DHW mode a demand is received by drawing >2.5 litres per second from a hot tap.
If the lamp is lit the boiler is on, or is starting up, to serve the demand for that function. If the lamp
is flashing the demand is still present but the burner is off because the unit exceeded the desired
temperature and the forced anti-cycle (in CH mode) delay has not elapsed.
6.3
FAULT MODES
If a situation is detected which the boiler considers may cause damage to the appliance the boiler
will enter a lockout mode and stop functioning. After clearing the problem the user must also press
the “Reset” button once to resume boiler operation. TURNING THE POWER ON THEN OFF
WILL NOT CLEAR A LOCKOUT SITUATION
WD388/0/2004
Chapter 6 : Fault Finding
The Keston C36 & C36P Combi Boilers
Installation & Servicing Instructions
Page : 26
