3.1 Commission the Boiler
Automatic Air Vent:
This is built into the pump.
L
eave
the cap open during and after commissioning.
M
anual Air Vent:
This must be used to remove as much
air as possible before firing the burner.
Warning: Do not attempt to start this boiler unless
the primary circuit has been filled with water.
Preliminary Electrical System Checks
These chec
k
s must be carried out prior to attempting to
start the boiler. They are, Earth
C
ontinuity, Short
C
ircuit,
P
olarity & Resistance to Earth.
Flush the System
The system must be flushed in accordance with BS
75
93
and the flushing agent manufacturers instructions.
Further guidance can be obtained from BS
5
449 Section
5
.
Gas Soundness
P
urge and test for soundness in accordance with BS6
8
9
1
or I.S.
81
3. The inlet pressure test point of the gas valve
is indicated opposite. The appliance gas coc
k
operation is
shown in Fig. 9A page 20.
Unvented Domestic Hot Water System
1
. Open one or more hot water taps.
2. Turn on mains water supply and observe air free
water issuing from tap(s)
3.
C
lose tap(s) and chec
k
mains water pipewor
k
for
lea
k
s
4.
C
hec
k
that all factory-made plumbing connections
are tight and lea
k
free (and have not loosened in
transit).
5
. Manually operate both the Temperature &
P
ressure Relief Valve and the secondary pressure
relief valve and ensure that the discharge from
these valves emerges safely.
C
lose them again
with a “snap” action.
Guideline times for the initial heat-up and recovery
for a nominal
5
0 °
C
temperature rise (e.g.
15
°
C
-
6
5
°
C
) within the store are:
Unit Heat-up
Recovery*
90
L
itre
18
min.
15
min.
115
L
itre
22 min.
18
min.
15
0
L
itre
30 min.
23 min.
* From previous draw-off of
7
0% of volume.
Sealed Primary System
1
. Ensure that gas supply is turned OFF at the gas
coc
k
.
2.
L
eave the boiler switched OFF at the selector switch
but turn both the
C
H and DHW control
k
nobs cloc
k
wise.
3. Move the indicator lever on the diverter valve head to
the mid position and push in so that it “latches”.
4.
C
hec
k
that the isolating valve on the by-pass lin
k
is
O
P
EN (slot in-line with body).
5
. Attach a length of hose to the outlet of the manual
vent (
1
/4” manometer tube is suitable). Open the vent
using a radiator
k
ey.
6. Open the automatic air vent cap (above the pump) by
one turn.
C
hec
k
that filling loop is connected and
supplied with water.
7
. Open both valves on the filling loop and fill system
with water. Allow water to flow from the manual vent
until air is no longer discharged.
8
. Turn the (
L
H) selector switch cloc
k
wise to the DHW
position and use the HW/ENTER button on the
programmer to select hot water on A
LL
DA
Y
or 24HR
NOTE:
Full details of how to set up and use the
programmer are in the Users Instructions.
9.The pump and diverter valve should now operate
allowing more air to be expelled. (Free the pump
spindle if it appears to be stic
k
ing).
1
0. The boiler control will go to loc
k
out after about a
minute.
C
lose the manual vent. Reset using the selector
k
nob, turn the gas ON and allow the boiler to start
heating the cylinder contents.
11
. After approx.
5
minutes, central heating can be
selected by using the selector switch and programmer.
1
2. If a fault is suspected, consult the list of Error
C
odes
on page 4
7
.
Inlet
P
ressure
P
oint
Outlet
P
ressure
P
oint
30
© Baxi Heating UK Ltd 2015