IDEAL Concord Super Series 4 100 V, Установка и обслуживание

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3 Concord Super Series 4 -
Installation & Servicing
BOILER DESCRIPTION
Each boiler consists of;
a. The insulated stainless steel casing with flue outlet, flue
coupling point and condensate drain.
b. The heat exchanger module(s).
c.
The module control pack.
d. Wiring centre with high & low voltage wiring harnesses
and in case of multi-module boilers;
e. Gas header - complete with individual module gas
service taps and mains inlet gas tap.
f. Flow and return water headers.
g. Each boiler is supplied with instructions for installation
and use.
The 50kW boiler is supplied with a module gas service tap
only.
Each module is connected in parallel across the flow and
return water headers, ensuring that water is flowing through all
of the modules at all times.
The
Ideal Concord Super range of boilers provides good load
matching & sequence control by the following method:
As the load on the boiler decreases so the return water
temperature increases.
Each module is fitted with an electronic thermostat capable
of being set to within 0.5ºC. These thermostats sense the
return water temperature.
Once the flow temperature reaches 82ºC (i.e. the return
reaches 71ºC) the modules are set to switch off at intervals
to maintain the flow at 82ºC ± 3ºC.
With basic controls the modules switch off from left to right
and from top to bottom. Thus the top left module is always
the first to go off and the bottom right the last.
The standard wiring centre, on the side of the boiler, is
the connection point for the mains supply, the low gas
inlet pressure and low water pressure switches - provided
for boiler protection. The centre also provides facilities
for the wiring in (via voltage free connections) of remote
indicators/alarms, for ‘burner on’, ‘lock out’ and ‘overheat’.
(Indicating that at least one module is in the signalled
condition).
Facility is also provided for the connection of the ‘Boiler
Management System’. Additional controls such as water
flow switch, programmer, energy management systems
etc. may also be used.
MODULE DESCRIPTION
Each module can be sub-divided into 4 main elements:
a. The heat exchanger, which consists of finned copper
tubes expanded into cast iron end plates, and cast iron
flow and return elbows (refer to Frame 15).
b. The gas line, which supplies and regulates the gas flow
to the burner (refer to Frame 17).
c.
The fan assembly, which draws gas (from the injector)
and air, mixes them and supplies the mixture to the
burner. (Refer to Frame 16).
d. The electrical control assembly.
MODE OF OPERATION
The normal mode of operation of the boiler is preceded, in
certain conditions, by a period in which the complete boiler
casing is given a three volume air change. The air change is
an important safety feature of the European requirements, with
which the boiler is designed to comply.
The air change will occur whenever the boiler goes form a
situation of no modules firing to a situation of one module
firing. This includes morning start-up and those occasions of
low load when the last module firing goes off on its thermostat
(or external controls) and is called again.
The air change will NOT occur if one or more modules are
firing and a further module is called.
The three volume air change period operates as follows, in the
case of multi-module boilers: All the module fans are energised
and run for a period of not less than 30 seconds. At the end of
this period all the fans switch off.
After a delay of approximately 1 second, the fan of the module
being called begins its 15 second pre-purge period. Refer to
Frame 30.
In the case of single module boilers: only its own 15 second
nominal pre purge period occurs.
When the electronic adjustable control thermostat calls for
heat, the fan is switched on and purges the combustion
chamber for 15 seconds. At the end of this time the ignition
sequence starts; the control box delivers a spark from the
ignition electrode to the burner and the gas valves are opened.
Gas is delivered, via the injector, to the distribution plate at the
inlet to the fan. This pre-mixes the gas with the air which then
passes from the fan through a multi-hole plate to the burner,
where it is ignited. The flame is sensed via the ionization
electrode and the controls keep the valves open until the
thermostat is satisfied.
The module is protected against blockage of the burner,
heat exchanger or flue, and against fan failure by the gas/
air control. This senses the difference in pressure across
the multi-hole plate and controls the gas injector pressure
according to the amount of air flowing.
After combustions, the products flow past the finned copper
tubes and through the gas distribution screen into the boiler
casing. In doing so, heat is given up to the water flowing
through the tubes.
The installation must also conform to current building
regulations, any requirement of the local authority health
and safety executive, as region, insurance companies and
the Health and Safety at Work Act 1974. All wiring must
conform to I.E.E. (BS. 7671) regulations for the electrical
equipment of buildings.
The boiler modules are very quiet in operation and no
additional noise soundproofing is required.
GENERAL