Caring For Your Boiler; Checking Sealed System Pressure; How To Fill Or Top Up Your Sealed System - Grant Vortex Combi Series User Instructions

3 CARING FOR YOUR
BOILER
3.1

CHECKING SEALED SYSTEM PRESSURE

All Grant Vortex combi boilers operate as part of a sealed system.
Your installer will have pressurised the system and should have
told you (or set it on the pressure gauge) the system pressure
when cold. This pressure is normally between 0.5 and 1.0 bar,
which will increase slightly when the system is hot.
*This is the
pressure inside
the heating
system while the
system is hot.
Figure 3-1: Pressure gauge during normal boiler operation
You should frequently check that the system pressure is correct.
If the pressure (when the heating system is cold) is below the set
pressure mentioned above, you can re-pressurise the system by
following the instructions given in Section 3.2.
If the system requires re-pressurising frequently, ask your installer
or service engineer to check the heating system for leaks and to
check the expansion vessel air charge.
AIR VENTS
The boiler and/or system will be fitted with an air vent to remove
air from the system.
Any air trapped in the radiators should be removed by venting the
radiators using the vent screw at the top of each radiator. Only
vent a radiator if the top is cool and the bottom is hot. Excessive
venting will reduce the system pressure, so only vent when
necessary and check the system pressure as mentioned above.
Re-pressurise the system if necessary.
PRESSURE RELIEF (SAFETY) VALVE
The boiler is fitted with a safety valve to release excess pressure
from the system. If water or steam is emitted from the safety valve
discharge pipe, switch off the boiler and contact your installer or
service engineer immediately.
Section 3: Caring for your Boiler
2
3
1
0 4
3.2 HOW TO FILL OR TOP UP YOUR
SEALED SYSTEM
(filling loop)
Figure 3-2: Sealed system filling loop arrangement
To fill or top up your heating system, proceed as follows:
1. Check the boiler and circulating pumps are switched off and
any air vents on the system are open.
2. Connect the filling loop* between the two filling valves.
3. Open the filling valve on the mains water end of the filling
loop (the valve is open when the operating lever is in line with
the valve).
4. Open the filling valve on the heating end of the filling loop to
allow water to flow into the heating system (the valve is open
when the operating lever is in line with the valve).
5. When the pressure gauge shows the required cold system
pressure (refer to Section 3.1) close the filling valve on the
heating system.
6. Vent each radiator to remove any air that may be trapped
in them. Start with the lowest radiator in the system, i.e
downstairs.
7. Locate the circulating pump(s) and vent the pump(s) by
following the manufacturer's instructions.
• Refer to Appendix A1 or A2 (as appropriate) at the back
of the boiler's installation and servicing instructions for
the pump venting procedure.
8. Now, check the system pressure on the system pressure
gauge. If necessary, re-open the filling valve on the system
until the gauge shows the required pressure. Take care not
to over-fill!
9. Finally, close both filling valves and disconnect the filling loop
at one end only. Take care, as the filling loop may contain
water!
*Grant Vortex combi boilers come with the filling loop installed
inside the boiler casing, but if you cannot locate the filling loop,
please contact your installer.
! NOTE !
If the system has been drained down or requires frequent
topping up, then the level of inhibitor and/or anti-freeze will
need to be checked by your installer.
! WARNING !
Only add water to the system when the system is cold and
the boiler is switched off.
Do not overfill
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