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COMMISSIONING & TESTING
5
5.1
FILLING THE WATER SYSTEM
Befor
e commissioning the appliance, the whole gas installation
including the meter
MUST
be pur
ged and tested for gas tightness
in accordance with BS 6891: 1998.
Open all doors and windows, extinguish naked lights,
and
DO NOT SMOKE
whilst purging the gas line.
!
It is recommended, where possible, to flush the CH
system without the appliance connected, to avoid debris
and flux blocking the waterways within the appliance.
Befor
e commencing the commissioning procedure, ensure that the
gas service cock is turned on, the electricity supply is isolated,
and that the CH and DHW pipe-work is complete. Fill the water
systems by following the procedure detailed below steps 1 to 5,
and referring to Figure 17.
17
1)
Check that the CH flow and r
eturn valves are in the open
position.
2)
Fill the system with water using one of the appr
oved methods
described in section 3.7 to about 2.0 bar. Vent the system via the
radiator valves and system air vents in accordance with normal
practice. Ensure that all system air vents are closed.
3)
Check the system for soundness.
4)
Check the operation of the pr
essure relief valve (Figure 18) by
pulling the lever out gently to ease the valve of its seat. Checking
that water is discharged, release the lever and ensure that the
valve seats correctly and does not leak.
5)
Drain the entir
e system using the manual drain valve to flush
out any debris, and refill to 0.2 bar above the system design
pressure (between 0.5 and 1.0 bar) by repeating the above
procedure. Follow the commissioning procedure described below,
and then repeat this instruction with the system hot. It is
recommended that the system is cleaned with a recognised system
cleaner such as Fernox or Sentinel.
6)
Open the DHW inlet valve and open and close each hot
water tap in turn to clear all the air from the pipes and the
appliance.
7)
Remove the pump cap; use a scr
ewdriver to rotate the pump
shaft. Replace the cap.
8)
If a filling loop has been used, disconnect filling loop.
9)
Prior to lighting the appliance check that the gas inlet
pressure measured at the appliance inlet pressure test point is
>20±1 mbar for natural gas. (as described in section 5.2 b), the
central heating system should also be checked for circulation by
operating the appliance with the gas turned off, this is to ensure
that no air locks occur. The appliance may go into ignition
lockout and require resetting (see section 5.5).
T
o aid venting, a manual air vent is provided on the top
LHS of the appliance, and an automatic air vent on the
pump assembly
Do not use the pressure relief valve to drain the system,
because dirt or debris could prevent the valve seating
correctly. If the valve leaks or sticks closed, then replace it.
T
o drain the system, open the manual drain on
the side of the CH flow cock shown in figure 18.
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