Keston C110, C90 Installation Manual

WD356/0/2003

Users Instructions For C90

and C110 Models

The Gas Safety (Installation And Use) Regulations: 1996 (as amended) impose certain statutory

obligations on gas users. Further information regarding these regulations can be obtained from your
Gas Supplier.

All gas appliances must be installed by competent persons by law in accordance with these
regulations. Membership of CORGI is indication of such a competent person with regard to gas
installation.

It is in your interests, and that of safety, to ensure that the appliance is installed correctly and that the
law is complied with. Failure to do so could lead to a hazardous &/or potentially dangerous situation.

Introduction

These instructions should be carefully read to ensure safe and economical
use of your boiler.
The Keston C90 and C110 are high efficiency central heating condensing
boilers designed to provide central heating and indirect sanitary hot water
supply. They are designed for use with fully pumped systems only. The C90
and C110 models are supplied for natural gas use only.

Servicing

To ensure continual safe and efficient operation of the boiler it is
recommended that the appliance be checked and serviced as necessary at
regular intervals. Generally once per year will be sufficient. It is the law that
any servicing must be carried out by a competent person.
NB: There are no user serviceable parts inside the boiler cabinet. The

cabinet should only be removed by a qualified competent person.

Clearances

If fixtures are to positioned close to the boiler the following minimum
clearances must be observed: Top : 350 mm, Bottom : 150 mm, Left : 25 mm,

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Right : 25 mm & Front : 305 mm. Extended clearance is required to the front
to allow for access for servicing.

Cleaning

Normal casing cleaning only requires dusting with a dry cloth. To remove
more stubborn marks wipe with a damp cloth and finish with a dry cloth.

Boiler Setup

WD356/0/2003

1) Check that the gas supply from the gas meter is turned ON

2) Switch on the electric supply to the boiler and controls and set the heating
controls to call for heat.

To Light The Boiler

The C90 and C110 boilers incorporate dual thermostats to allow two different zones
to be connected to operate at two different temperatures. Generally the central
heating zone is connected to zone 1 and the DHW calorifier to zone 2. You should
ask your installer to advise whether your boiler serves one or two zones.

To set thermostat temperatures you must turn the relevant knob to the required
position. As you turn the knob both the displays, one for each module, will change to
either “c nn” or “d nn”, depending on the knob being turned. As the knob is turned the
required temperature (the last two digits of the displays) change. Set the knob to the
position which gives the required temperature. When the knob is released the
display, after a few seconds, will return to normal.

If the boiler detects whether zone requires heat the following sequence will occur:

1) The fan and pump will start inside the module and the displays will indicate “1
nn” to show the boiler modules have started the first stage of the ignition
sequence.

2) After 5 seconds the displays will change to “2 nn” to indicate the spark ignition
of the sequence has started.

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