Grant Spira 5-18, Инструкция для пользователя, по установке и обслуживанию

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An automatic air vent should be fitted to
the highest point of the system.
If thermostatic radiator valves are fitted
to all radiators, a system by-pass must
be fitted. The by-pass must be an
automatic type.
All fittings used in the system must be
able to withstand pressures up to 3 bar.
Radiator valves must comply with the
requirements of BS 2767:1991.
One or more drain taps (to BS 2879)
must be used to allow the system to be
completely drained.
6.2 Filling the Sealed System
Filling of the system must be carried
out in a manner approved by the local
Water Undertaking.
The procedure for filling the sealed
system is as follows:
1. Check the air charge pressure in
the expansion vessel BEFORE filling
the system.
The expansion vessel charge pressure
should always be slightly greater than
the maximum static head of the system,
in bar, at the level of the vessel (1 bar =
10.2 metres of water). See Figure 6-1.
The charge pressure must not be
less than the actual static head at
the point of connection.
2. Check that the small cap (or screw)
on all automatic air vents (including
the one fitted at the left rear of the
boiler) is open at least one turn.
The cap (or screw) remains in this
position from now on.
3. Ensure that the flexible filling loop is
connected and that the double
check shut off valve connecting it to
the water supply is closed. A valve
is open when the operating lever is
in line with the valve, and closed
when it is at right angles to it.
3. Open the fill point valve.
4. Gradually open the double check
valve from the water supply until
water is heard to flow.
5. When the needle of the pressure
gauge is between 0.5 and 1.0 bar,
close the valve.
6. Vent each radiator in turn, starting
with the lowest one in the system,
to remove air.
7. Continue to fill the system until the
pressure gauge indicates between
0.5 and 1.0 bar. Close the fill point
valve. The system fill pressure (cold)
should be 0.2 - 0.3 bar greater than
the vessel charge pressure – giving
typical system fill pressures of
approx 0.5 bar for a bungalow and
1.0 bar for a two storey house.
Refer to the Domestic Heating
Design Guide for further information
if required.
8. Repeat steps 5 and 6 as required
until system is full of water at the
correct pressure and vented.
9. Water may be released from the
system by manually operating the
safety valve until the system design
pressure is obtained.
10. Close the fill point and double
check valves either side of the filling
loop and disconnect the loop.
11. Check the system for water
soundness, rectifying where
necessary.
6.3 Venting the Pump
For those heating circulating pumps
fitted with a vent plug, it is important
that the pump is properly vented to
avoid an air lock and also prevent it
running dry and damaging the bearings.
Unscrew and remove the plug from
the centre of the pump motor. Using a
suitable screwdriver, rotate the pump
spindle about one turn. Replace the
plug in the motor. Do not over tighten.
6.4 Pressure Relief (Safety)
Valve Operation
Check the operation of the pressure
relief (safety) valve as follows:
1. Turning the head of the valve
anticlockwise until it clicks. The click
is the safety valve head lifting off its
seat allowing water to escape from
the system.
2. Check that the water is escaping
from the system.
3. Top-up the system pressure, as
necessary.
Only ever fill or add water to the
system when it is cold and the
boiler is off. Do not overfill.
!
WARNING
!
NOTE
The expansion vessel air pressure,
system pressure and operation of
the pressure relief valve must be
checked on an annual service. Refer
to Section 11.
!
NOTE
The air charge pressure may be
checked using a tyre pressure
gauge on the expansion vessel
Schraeder valve. The vessel may
be re-pressurised, when necessary,
using a suitable pump. When
checking the air pressure, the water
in the heating system must be cold
and the system pressure reduced
to zero.
!
NOTE
Some heating circulating pumps are
not fitted with a vent plug so it is not
possible to vent these pumps in the
manner described above.