10
REGULATION
FLOW SWITCHES
Temperature regulation for C/H circuit is controlled by 1 thermistor. The C/H
knob allows the adjustment of temperature between 35 and 85°C.
Resistance value are
- 5000
Ω
at 25
°C
- 2631
Ω
at 40°C
- 620
Ω
at 80°C
- 255
Ω
at 110°C
Flow in Heating circuit is detected by 1
flow switche. A piston with a magnet at
the top operates a REED switch. The
piston is lifted by flow rates listed below :
Flow rate threshold :
C/H 250 l/h ±20 l/h
ROUTINE SERVICING
To ensure continued efficient operation of the appliance, it is recommended that it is checked and serviced as necessary at reg-
ulars intervals. The frequency of servicing will depend upon the particular installation condition and usage, but in general, once
a year should be adequate.
It is the law that any service work must be carried out by a competent person such as your local Chaffoteaux Service Centre,
British Gas or other CORGI registered personnel in accordance with the current Gas Safety (Installation and Use) regulation.
Attention ! the air/gas connection pipe between the gas valve and the burner should never open. The seal can be checked only
in the factory.
The service schedule should include the following operations :
- Check the pressure in the system
- Check the correct operation of the appliance
- Check the correct operation of the gas controls
- Check the functions of safety controls
- Clean the electronic board of the fan located on the gas valve assembly and the different transformers in the sealed chamber.
- Check combustion chamber insulation panels for damage
- Check the lighting and ionisation electrodes condition
- Clean the burner (Never use metallic brush which can damage the stainless steel)
- Clean the heat exchanger (Never use metallic brush which can damage the stainless steel)
- Clean the siphon and pay attention to the acidity of its contents
- Check the correct seal of the drain system
- Clean gas and water filters
- Check expansion vessel charge pressure
- Clean an check operation of safety valve
- Check the correct seal of the flue system.
Additional procedures that may be necessary :
- Check the burner pressure and the gas flow rates
- Check, clean or replace components as necessary
- Carry out combustion test utilising the test points in the flue turret
Suggested sequence for servicing :
Before disconnecting or removing any part, isolate the gas and electricity supplies. Ensure that the appliance is cool, and take
care about the condensats products content in the siphon which are acid.
(For detail, please see section on Parts Removal and Replacement)
Preliminary checks
- Remove outer case
- Check the system pressure is at least 0.7 bar cold
- Check that the burner is extinguished fully when both solenoids are closed and fan is off.
- Test ionisation functions and check that lockout occurs by turning off gas tap.
- Whilst boiler is operating, check operation of the primary flow switch by closing heating flow valve and by pass screw (turn
clockwise ) noting the number of turns so that it may be reset correctly.
- Control the correct flood of condensats in the siphon which is transparent.