Buderus Logamax plus GB162-100 kW User manual

Gas valve replacement Condensing gas boiler
Logamax plus
GB162-80 kW/100 kW
6 720 615 152 (01/2008) US/CA
For the contractor
Please read these
instructions carefully!
Required Input Rates
This instruction is for replacing the gas valve for the GB162 model
boilers with Natural Gas.
Notice! Save these instructions for later use.
Logamax plus GB162-80 kW
290,000 btu/hr
Logamax plus GB162-100 kW
333,000 btu/hr
WARNING!
Replacement of a gas valve must be done by a qualified service
agency in accordance with the manufacturer's instructions and
all applicable codes and requirements of the authority having
jurisdiction.
The information in these instructions must be followed to
minimize the risk of fire or explosion or to prevent property dam-
age, personal injury or death. The qualified service agency is
responsible for the proper installation of this gas valve.
The installation is not proper and complete until the operation of
the converted boiler is checked as specified in the manufac-
turer’s instructions supplied with the gas valve.
CAUTION!
The gas supply shall be shut off prior to disconnecting the elec-
trical power, before proceeding with the conversion.
Instructions

Contents
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications!
2
Contents
1 Safety considerations 3
1.1 Application purpose 3
1.2 Hazard definitions 3
1.3 Observe the following symbols 3
2 Parts list 4
3 Gas valve replacement 5
3.1 Testing for gas leaks 9
3.2 Inlet gas pressure 9
3.3 Checking and adjusting the gas/air ratio 11
3.4 Carrying out a tightness test in operating
conditions 12
3.5 Measuring the carbon monoxide
content (CO) 12
3.6 Lighting Instructions 13
4 Operating Instructions 14

1Safety considerations
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications! 3
Contents
1 Safety considerations
For use in Canada the gas valve replacement shall be
carried out in accordance with the requirements of the
provincial authorities having jurisdiction and in accor-
dance with the requirements of the CAN-B149.1 and
CAN1-B149.2 Installation Code. See also E.I.V.
Please observe the following safety instructions.
1.1 Application purpose
This document describes how to replace the gas valve
for the Logamax plus GB162-80 kW/100 kW.
1.2 Hazard definitions
The following defined terms are used throughout the
documentation to bring attention to the presence of
hazards of various risk levels. Notices give important
information concerning the operation of the product.
1.3 Observe the following symbols
DANGER:
Indicates the presence of hazards that will
cause severe personal injury, death or
substantial property damage.
WARNING:
Indicates the presence of hazards that can
cause severe personal injury, death or
substantial property damage.
CAUTION:
Indicates presence of hazards that will or
cause minor personal injury or property
damage.
CAUTION:
Risk of electric shock.
Indicates presence of hazards due to elec-
tric shock.
NOTICE:
Indicates special instructions on installa-
tion, operation or maintenance that are
important but not related to personal injury
or property damage.
DANGER
due to explosion of gas.
zWork only on gas components when
you have a license to do so.
zNote that the assembly of gas and vent
connections, the initial start-up, the
electrical connections, the maintenance
and service can only be performed by a
licensed service contractor or techni-
can.
DANGER
due to electricity.
zPrior to doing any work on the heating
system, disconnect all electrical power
to the appliance at the emergency
switch.
zIt is NOT sufficient to shut off only the
appliance control!

2Parts list
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications!
4
2 Parts list
The gas valve spare part for the 80 kW/100 kW
#7746900399 includes:
–assembly # 774601465A
zgas valve Natural Gas
zventuri
zorifice # 432.438A (dia. 8.40 mm / 0.331 inch)
–bag
–these instructions
–o-ring (fan-venturi)
–sealing (gas pipe)
–Torx keys Tx25 and Tx30
–Torx screws (flange).
Thermal
power
gas
boiler
Type of
gas
supply
Attitude
in ft
Gas orifice
diameter in
mm (inch)
Venturi
article
number
GB162-
80 kW
Natural
gas 0 - 10,200 8.40 (0.331) 73983
GB162-
100 kW
Natural
gas 0 - 10,200 8.40 (0.331) 73983
Table 1 Gas orifice diameter

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications! 5
3 Gas valve replacement
To replace the gas valve the following instructions must
be adhered to:
Shut down the boiler
zTurn off the gas supply underneath the boiler.
zSwitch off the heating system using the main switch
(fig. 1).
zDisconnect the electrical power to the boiler.
zSet the thermostat or other operating control to
lowest setting.
zOpen the boiler door by turning the vent key through
¼ rotation (fig. 2).
DANGER
if flammable gas explodes.
Only carry out work on gas conduits and
fittings if you are licensed for such work.
fig. 1 Mains switch
Reset
01
1
140
130
120
90
100
110
Aut
0
Eco
190
170
150
130
90
110
Aut
0
fig. 2 Opening the boiler door
1
2
3

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications!
6
Changing the gas valve assembly
zLoosen the screw connection on the gas valve
(fig. 3, pos. 1) and pull the plugs (fig. 3, pos. 2) from
the gas valve.
zPull both plugs from the fan unit (fig. 4, pos. 1).
zPull the air suction tube from the fan (fig. 5).
fig. 3 Undoing the connections to the gas valve
1 2
2
fig. 4 Removing the connectors from the fan
1
fig. 5 Pulling the air suction tube from the fan

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications! 7
zLoosen both retaining clips on the burner cover
(fig. 6).
zRemove the burner cover together with the fan unit
and the gas valve (fig. 7).
zUndo the three screws (fig. 8, pos. 1) and remove
the gas valve with the venturi from the fan unit
(fig. 8, pos. 2).
zTake the gas valve and venturi from the box.
zInstall the venturi and gas valve on the fan unit using
a new O-ring (fig. 9) and follow the instructions
above in reverse order.
fig. 6 Opening the retaining clips
fig. 7 Removing the burner cover with the gas/air unit
fig. 8 Removing the screws and gas valve with venturi
2
1
fig. 9 Placing a new O-ring on the fan unit

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications!
8
zInstall the gas flange from the natural gas assembly
on the new gas valve (fig. 10, pos. 1).
zRemove the seal from the gas pipe and install a new
seal (fig. 11).
zRefit all parts in reverse order. When re-installing
the burner plate, make sure that the notch is on the
right-hand side (fig. 12).
zCarry out the start-up activities and complete a new
start-up report.
zAlso check all joints and gaskets affected by the
installation activities while carrying out the tightness
test in operating conditions.
zClose the boiler door and lock the fastener by turn-
ing the vent key through ¼ rotation in a clockwise
direction.
fig. 10 Installing the gas flange
1
fig. 11 Installing a new seal on the gas pipe
fig. 12 Re-installing the burner plate

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications! 9
3.1 Testing for gas leaks
Prior to start-up of the boiler you must check the exter-
nal tightness of the gas supply valve and confirm this in
the start-up report.
zDisconnect the heating system from the power
supply.
zCheck the exterior tightness of new conduit sections
up to and including the direct sealing point on the
gas burner fitting. The maximum test pressure
allowed on the input of the gas burner fitting is
60 inch W.C. (150 mbar).
zCheck the input rates to the values on the front
page.
3.2 Inlet gas pressure
zOpen at least one thermostatic radiator valve if
present to allow water to flow through the boiler.
Do not switch on the boiler.
zClose the gas shut-off valve. Loosen the screw plug
on the inlet gas pressure testing nipple by two turns
(fig. 13, pos. 1).
zConnect the pressure gauge connection hose to the
testing nipple (fig. 13, pos. 2).
zSlowly open the gas shut-off valve.
The boiler and its individual shutoff valve must be dis-
connected from the gas supply piping system during
any pressure testing of that system at test pressures in
excess of 60 inch W.C. (150 mbar).
WARNING !
–Cover endangered positions before leak
testing.
–Do not spray the leak testing agent onto
cables, plugs or electrical connection
lines. Do not allow it to drip onto them
either.
DANGER !
Leaks may be caused to pipes and screw
connections during commissioning and
maintenance activities.
–Carry out a proper leak test.
–Only use approved leak detection
agents for leak detection.
fig. 13 Measuring the gas supply pressure
1
2

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications!
10
The boiler must be isolated from the gas supply piping
system by closing its individual manual shutoff valve
during any pressure testing of the gas supply piping
system at test pressures equal to or less than 60 inch
W.C. (150 mbar).
zBriefly press on the control panel cover to open it.
zSwitch on the heating system by setting the main
switch to position "1" (see fig. 1, page 5).
zPress the "Chimney Sweep" dbutton and hold it
(for approx. two seconds) until the display shows a
decimal point.
zMeasure the gas connection pressure as soon as
the "Burner" LED lights and enter this value in the
start-up report.
The inlet gas pressure must be:
–for natural gas - min. 7.0 to 10.5 inch W.C. (17.4 to
26.1 mbar), nominal supply pressure 8.0 inch W.C.
(19.9 mbar).
zRepeatedly press the "Service" ebutton until the
temperature indication is displayed.
zPress the "Chimney Sweep" dbutton to end the
measurement procedure.
zClose the gas shut-off valve.
zRemove the connection hose again and tighten the
screw plug on the testing nipple.
zOpen the gas shut-off valve again.
fig. 14 Opening the control panel
CAUTION
–Contact the relevant gas utility company
if the required inlet gas pressure is not
available.
–Install a gas pressure regulator before
the gas burner fitting if the supply pres-
sure is too high.

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications! 11
3.3 Checking and adjusting the gas/air
ratio
zSwitch off the heating system using the main switch.
zLoosen the screw plug on the measuring nipple for
the burner pressure by two rotations (fig. 15,
pos. 1).
zSet the pressure gauge to zero.
zUse a hose to connect the plus terminal of the pres-
sure gauge to the burner pressure measuring nipple
(fig. 15, pos. 2).
zSwitch on the heating system using the main switch.
zPress the "Chimney Sweep" dbutton and hold it
(for approx. two seconds) until the display shows the
decimal point.
zPress and hold the "Chimney Sweep" dand "Ser-
vice" ebuttons (for approx. five seconds) until the
display shows "Lxx" (e. g. L80).
zSet the boiler to partial load "L25" for the 80 kW and
"L20" for the 100 kW boiler by pressing the "Chim-
ney Sweep" dbutton (higher values) or the
"Reset" cbutton (lower values).
zRead out the differential pressure.
The differential pressure (pGas –pAir) must be
-0.02 inch W.C. (- 5 Pa) (±0.02 inch W.C. = ± 5 Pa)
(read-out on pressure gauge: -0.04 – 0 inch W.C. =
-10 – 0 Pa).
zEnter the value measured in the start-up report.
zIf the gas/air ratio is not correct it can be adjusted
using the adjustment screw (fig. 16, pos. 1). The
adjustment screw is located behind the cover screw.
zRepeatedly press the "Service" ebutton until the
temperature indication is displayed.
fig. 15 Checking the gas/air ratio
2
1
+
= higher values = lower values
fig. 16 Setting the gas/air ratio
1

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications!
12
zPress the "Chimney Sweep" dbutton until the
decimal point is cleared from the display.
zSwitch off the heating system using the main switch.
zRemove the measurement set-up, tighten the screw
in the burner pressure measuring nipple.
zSwitch on the heating system using the main switch.
3.4 Carrying out a tightness test in
operating conditions
zCheck all gaskets and joints in the burner gas circuit
for leaks while the burner is operational, using a
foaming agent.
3.5 Measuring the carbon monoxide
content (CO)
zMeasure the carbon monoxide content on the flue
gas sampling point (fig. 17, pos. 1).
The CO values in an air-free condition must be below
400 ppm or 0.04 vol. %.
Values of 400 ppm and up indicate that the burner
adjustment may be wrong, the gas burner fitting or the
heat exchanger are dirty or that there may be burner
faults.
zYou must establish and resolve the cause.
The boiler must be operational when you do this.
DANGER !
Leaks may be caused to pipes and screw
connections during start-up activities if
flammable gas explodes.
–Only use approved leak detection
agents for leak detection such as a
soapy water solution.
CAUTION
due to a short circuit.
–Cover damageable parts before leak
testing.
–Do not spray the leak testing agent onto
cables, plugs or electrical connection
lines. Do not allow it to drip onto them
either.
fig. 17 Measuring the carbon monoxide content
1

3Gas valve replacement
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications! 13
3.6 Lighting Instructions
For your safety, read before lighting.
A) This boiler is equipped with an ignition device which
automatically lights the pilot. Do not try to light the
pilot by hand.
B) Check for smell of gas around the boiler area.
Be sure to smell next to the floor because some gas
is heavier than air and will settle on the floor.
C) Do not use this boiler if any part has been under
water. Immediately call a qualified service
technician to inspect the boiler and to replace any
part of the control system and any gas control which
has been under water.
WARNING !
due to not follow these instructions.
zIf you do not follow these instructions
exactly, a fire or explosion may result
causing property damage, personal
injury or loss of life.
zFollow these operating instructions.
DANGER !
What to do if you smell gas:
zNo open fire! Do not smoke!
zAvoid formation of sparks! Do not touch
any electric switch, phone, electric plug
or bell!
zShut off main gas supply.
zOpen windows and doors!
zNotify all occupants!
zLeave the building!
zImmediately call your gas supplier,
heating contractor or fire department
from a phone outside the building!

4Operating Instructions
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications!
14
4 Operating Instructions
Start up the boiler
STOP!
Read the safety precautions on page 13 of this manual.
zWait five (5) minutes to clear out any gas. Then
smell for gas, including near the floor. If you smell
gas, STOP! Follow "B" in the safety information on
page 13. If you do not smell gas, go to the next step.
zFit the casing again.
zOpen the gas shut-off valve.
zSet the thermostat or other operation control to
desired setting.
zConnect the heating system to the power supply.
zSwitch on the heating system using the main switch
(fig. 18).fig. 18
Reset
01
1
140
130
120
90
100
110
Aut
0
Eco
190
170
150
130
90
110
Aut
0

Notes
Logamax plus GB162-80 kW/100 kW - We reserve the right to make any changes due to technical modifications! 15

Bosch Thermotechnology Corporation
50 Wentworth Avenue
Londonderry, NH 03053
Tel.: [phone]
Fax: [phone]
www.buderus.net
Products manufactured by:
Bosch Thermotechnik GmbH
Sophienstrasse 30-32
D-35576 Wetzlar
www.buderus.de
Bosch Thermotechnology Corporation reserves the right to
make changes without notice due to continuing engineering
and technological advances.
6 720 615 152 (01/2008) 7218A