5
All installers are asked to follow the Benchmark Scheme by
adhering to the Code of Practise, which can be obtained from
www.centralheating.co.uk.
The Excel comprises a range of high-efficiency combination
boilers with outputs to DHW of 25kW and 29kW respectively.
These appliances – by design – incorporate electronic ignition,
circulating pump, expansion vessel, safety valve, pressure
gauge and automatic by-pass.
The Excel range is produced as room sealed, category II2H3P
appliances, suitable for internal wall mounting applications only.
Each appliance is provided with a fan powered flue outlet with
an annular co-axial combustion air intake that can be rotated
– horizontally – through 360 degrees for various horizontal
or vertical applications. The Excel can also be used with the
Vokèra twin flue system.
The Excel is approved for use with C13 & C33 type flue ap
-
plications.
These appliances are designed for use with a sealed system
only; consequently they are not intended for use on open
vented systems.
This booklet is an integral part of the appliance. It is therefore
necessary to ensure that the booklet is handed to the person
responsible for the property in which the appliance is located/
installed. A replacement copy can be obtained from Vokèra
customer services.
Fig. 4
General layout
1
Domestic hot water heat exchanger
2
Drain valve
3
Three porte valve actuator
4
Safety valve
5
Pump
6
Bottom auto air vent (AAV)
7
Main heat exchanger
8
Flues thermistor (NTC)
9
Fan assembly with mixer
10 Silencer
11 Flue gas analysis test point
12 Flue outlet & air intake
13 Ignition transformer
14 Top AAV+De-aerator
15 Spark Electrode
16 Sensing Electrode
17 Flow thermistor (NTC) - High limit thermostat
18 Expansion vessel
19 Pressure switch
20 Return thermistor (NTC)
21 Gas valve
22 Domestic hot water sensor
23 Condense trap
24 DHW flow switch
R Heating return connection
F
Heating flow connection
G
Gas connection
O
Hot water outlet
I
Cold water inlet
INTRODUCTION
INSTALLATION AND SERVICING INSTRUCTIONS
R F G O I
