Check the Operational (Working) Gas Inlet Pressure
1
. The gas valve is factory set and the burner pressure
changes as the fan modulates when demand on the boiler
alters. There are two important gas rates that relate to a
corresponding burner pressure that can be chec
k
ed as
verification during a gas rate chec
k
.
2. If necessary the gas rate may be chec
k
ed after running
the boiler for
1
0 minutes with any other appliances and
pilot lights turned off.
3. Ensure that the integral programmer and any external
controls are calling for heat, and the selector switch is in
the central heating and hot water position. The current
boiler temperature is shown on the display.
4. To chec
k
the gas rate it is necessary to set the boiler to
C
alibration Mode.
To carry out this operation
5
. Turn both temperature control
k
nobs fully anticloc
k
wise,
then quic
k
ly turn the DHW temperature
k
nob
1
/
4
turn
cloc
k
wise twice and bac
k
fully anticloc
k
wise.
6. The display will now alternate between SF and the
current boiler temperature and both green
L
EDs will flash.
8
. Turn
C
H temperature control
k
nob fully cloc
k
wise. As the
k
nob is turned the display will change from 0 to 00
indicating maximum rate, then revert to
P
alternating with
the current boiler temperature.
9. With the boiler operating in the maximum rate condition
chec
k
that the operational (wor
k
ing) gas pressure at the
inlet gas pressure test point is in accordance with B.S.
6
7
9
8
& B.S. 6
8
9
1
.
1
0. Ensure that this inlet pressure can be obtained with all
other gas appliances in the property wor
k
ing.
M
easure the Gas Rate
11
. With any other appliances & pilot lights turned OFF the
gas rate can be measured.
1
2. A gas rate measurement may now be made.
Approximate values are:-
Max 2.6
1
m
3
/hr
Min 0.
7
4 m
3
/hr
1
3. The
C
alibration Function is active for 20 minutes
unless the maximum
C
H temperature is exceeded.
1
4. The function can be disabled at any time by turning the
DHW temperature
k
nob.
Central Heating System
1
.
P
ress programmer
C
Hbutton to select heating
(indicated by red neon).
2.
C
hec
k
that any connected room thermostat is calling
for heat.
3. Note that when HWis selected the 3-way diverter
valve does not allow circulation to the
C
H circuit
until the storage cylinder contents have reached the
selected temperature. After filling with cold water,
this will normally ta
k
e between 20 to 2
5
minutes.
4. With flow to the
C
H circuit, bleed every radiator and
the pipewor
k
high points until all air or air/water mix
has been removed.
N.B.
L
eave the cap on the auto air vent (above the
pump) partially unscrewed so that the vent remains
operational - note that the burner control goes to safety
shut-down if the system pressure drops below 0.
5
bar.
I
M
PORTANT:
Do not vent the boiler with the burner
running or damage to the heat exchanger may result.
5
. Wait until the central heating circuit has reached its
normal temperature of approx.
8
0 °
C
before
balancing the radiators in the usual way to
achieve a temperature drop of
1
0 °
C
.
6. Allow system to reach full temperature (all radiators
at wor
k
ing temp.) and note “hot system” pressure.
Switch boiler off, drain and flush the system.
7
. Refill (using a suitable inhibitor) and remove all air
and air/water mix.
C
hec
k
the relief valve is not
“letting” by observing pipe outlet for several
minutes. (“
L
etting” is usually due to debris on valve
seat. Snapping the valve open-shut a few times will
normally cure this).
8
.
C
hec
k
that the system final pressure equals “hot
system” pressure as noted in
7
. above. Adjust if
necessary.
9. Set the room thermostat or programmer according
to the manufacturers instructions.
1
0.Disconnect filling loop flexible hose and leave in a
secure place for householder.
Domestic Hot Water System
1
. With the cylinder fully heated, chec
k
DHW output
temperature is approximately 4
5
to 6
5
°
C
(as
selected) using nearest tap and a flow rate of
approximately
5
l/min. Record inlet and outlet
temperatures in Benchmar
k
C
hec
k
list.
2. Measure hot water flow rate at bath tap (fully open)
and record in Benchmar
k
C
hec
k
list.
3. Refit outer covers in reverse order.
3.2 Hand Over to the User
1
. Explain the boiler controls
2. Give guidance if the system is to be shut down for
long periods when freezing is possible
3. Advise the User that for continued efficient and safe
operation of the boiler it is important that annual
servicing is carried out.
4. Explain how to re-start boiler if red neon indicates
loc
k
out.
5
. Hand over the Users Instructions.
6.
C
arefully read and complete all sections of the
Benchmar
k
C
ommissioning
C
hec
k
list at the rear of
this publication that are relevant to the appliance and
installation. These details will be required in the event
of any warranty wor
k
. The publication must be handed
to the user for safe
k
eeping and each subsequent
regular service visit recorded. For IE, it is necessary
to complete a “Declaration of
C
onformity” to indicate
compliance to I.S.
81
3. An example of this is given in
I.S.
81
3 “Domestic Gas Installations”. This is in
addition to the Benchmar
k
C
ommissioning
C
hec
k
list.
Min Gas Rate
Max Gas Rate
Burner
P
ressure
(mb)
0.6 - 0.
8
6.
8
-
7
.2
Gas
Rate
(m
3
/hr)
0.
7
- 0.
7
4
2.4
8
- 2.
7
4
C
O
(ppm)
2 - 30
30 -
1
00
C
O
2
(%)
8
.4 -
8
.
8
8
.
7
- 9.2
33
© Baxi Heating UK Ltd 2015