Rayburn Heatranger 480CD, Руководство по установке

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SEALED SYSTEM REQUIREMENTS
See Fig. 19
a. The installation must comply with the requirements
of BS 6798 and BS 5449. Maximum water 82°C
temperature.
b. A safety valve set to operate at 2 bar (30Ibf/In2)
shall be fitted in the flow pipe close to the boiler. There
must not be any valve between the safety valve and the
boiler. The valve should be positioned on a discharge
pipe fitted to prevent any discharge or creating a hazard
to occupants or cause damage to electrical components
and wiring.
c. A pressure gauge covering at least the range 0 to
4 bar (0 to 60 Ibf/In
2
) shall be fitted in the system, in a
visible position.
d. A diaphragm type expansion vessel to BS 4814 shall
be connected at a point in the return pipe close to the
boiler. The vessel must be chosen to suit the volume
of water in the cistern and the system charge must not
be less than the static head at the point of connection.
Further details can be obtained from ‘British Gas
Specification for Domestic Wet Central Heating Systems
Part 3 Sealed Systems’.
Vs = System Volume Litres
e. The hot water cylinder shall be either the indirect coil
type or a cylinder fitted with a calorifer which is suitable
for the system pressure.
f. The Make-Up System
Provision shall be made for replacing the lost water from
the system by either of the following methods:
a) From a make-up vessel or tank, and connected
through a non-return valve to the system on the return
side of the hot water cylinder or return side of all heat
emitters or radiators.
b)
Where access to a make-up vessel would be difficult,
by a remote automatic pressurisation and make-up unit.
OPEN SYSTEM REQUIREMENTS
If you are using an open system, the pressure sensor
on the flow pipe needs to be wired out of the system.
This is achieved by removing the RED link wire which
connects between the pressure sensor and the overheat
sensor. The remaining wire on the pressure sensor
should now be moved onto the spare terminal on the
overheat sensor.
N.B. It is very common on initial filling and
commissioning that air locks will cause the overheat
sensor to trigger a fault (A3). It is advisable to
temporarily connect the pump to the permanent Live and
Neutral so that it is continually running to vent the air.
To re-set the A3 fault, press the REPEAT button, once
the flow temperature drops below 60°C the boiler vents
all the air. You MUST re-connect the Pump Live and
Neutral into the correct terminals.
COMMISSIONING
Follow the commissioning instructions as for open
vented systems. See Section Commissioning
Instructions with the following additions:-
Fill the system until the pressure gauge registers 1.5
bar (22 Ibf/In
2
). Clear any airlocks and check for water
soundness.
Check the operation of the safety valve, by allowing the
water pressure to rise until the valve opens. The valve
should open with ±0.3 bar (±4.35 Ibf/In
2
) of the pre-set
pressure. If this is not possible conduct a manual check
and test.
Release cold water for initial filling pressure.
Any set pointer gauge should be set to coincide with the
recommended filling pressure.
Safety Valve Setting 2.0 bar
Vessel charge and
initial system pressure
0.5 bar 1.0 bar
0.16
L
Vs
x
0.16
0.09
L
Vs
x
0.09
Multiplying Factor
Expansion Vessel
volume (litres)
= System volume Vs x
factor
17
Sealed System
Fig. 18 DESN 514999