HAMWORTHY HEATING LTD
MILBORNE 500 SERIES
500001130/A
18
10.0 Gas Supply
Service Pipes
The local gas region must be consulted at the
installation planning stage in order to establish the
availability of an adequate supply of gas. An
existing service pipe must not be used without prior
consultation with the local gas region.
Meters
A new gas meter will be connected to the service
pipe by the local gas region, or a local gas region
contractor. An existing meter should be checked,
preferably by the gas region, to ensure that it is
adequate to deal with the rate of gas supply
required.
Gas Supply Pipes
Supply pipes must be fitted in accordance with BS
6891 or IGE/UP/2. Pipework from the meter to the
boiler must be of adequate size. Do not use pipes
of a smaller size than the boiler gas connection.
Each Milborne 500 series module is supplied with
an individual gas pipe which exits downwards on the
right hand side. The incoming mains gas supply
must be capable of supplying gas to the boiler at the
required pressure and volume, under all firing
conditions.
Boosted Supplies
Where it is necessary to employ a gas pressure
booster, the controls must include a low pressure
cut-off switch at the booster inlet. The local gas
region must be consulted before a gas pressure
booster is fitted.
Boiler House Control Valve
A manual valve for boiler house isolation shall be
fitted in the gas supply line. It shall be clearly
identified and readily accessible for operation,
preferably by an exit.
11.0 Power Supply & Wiring
The electrical drawing of the Milborne series 500
boiler assembly is shown in detail in figure 11.1
Some important electrical features of the boiler
assembly are specified on the appliance’s rating
plate.
Boiler installation requires the connection to a 230 v
– 50 Hz mains. The connection should be made in
full compliance with the applicable electrical
standards. However, it is always advisable to install
an electrical overload switch within the boiler’s
power supply.
Warnings
Always check the effectiveness of the earthing of
the electrical system to which the boiler assembly is
going to be connected. Indeed, should the earthing
be inefficient, the correct operation of the ignition/
detection electrode might be affected.
Warning:
230 V cables must be separated from the
24 V ones using independent PVC conduits.
Warning:
Before connecting external electrical
components (regulators, electrical valves, outside
temperature probes, etc.) to the boiler assembly,
make sure that their electrical features (voltage,
current, pickup voltage) are compatible with the
available inputs and outputs.
Warning:
Never switch off the boiler during normal
operation (when the burner is on), by means of the
on-off switch located on the underside of the boiler.
This will cause overheating of the primary
exchanger. To switch off the boiler (during normal
operation) use a room thermostat, a remote control
or the individual module on/off switch located on the
front of the respective boiler module.
Warning:
Do not touch electrical appliances with
wet hands.
Warning:
Do not expose the appliance to the
elements (rain, sun, wind, etc.). for internal use only.
Warning:
Do not pull or strain the electrical cables.
Warning:
Do not let the appliance be operated by
non-expert people. Should the power supply cable
break, isolate the boiler assembly. To replace it,
contact a qualified electrician.
Connection to Temperature Regulation Devices
Milborne series 500 boiler assemblies are fitted with
a very versatile control and management system,
which can manage up to three independent circuits
operating at different temperatures.
Figure 11.1 shows the main devices (probes,
circulators, valves, etc.) which form the three above-
mentioned circuits, directly controlled by the boiler’s
electronics. To connect these devices to the Boiler
assembly’s terminal strip, please see figure 11.1.
Note: Temperature sensors for the secondary
circuits are optional extras and must therefore be
specified when requesting quotations and placing
orders.
Programmable room thermostats for low and high
temperature heating circuits are available as 24hr or
7 day programmable versions.
