Buderus Logano GA124 User manual

6 720 804 895 – 2012/10 EN-US For heating engineers
Please read carefully before use
Conversioninstructions
from natural gas to propane
R o o m a i r - i n d e p e n d e n t
special g as- f i red boi l e r
Logano GA124
This conversion kit and the instructions are for conversion of the special gas-
fired boilers of the GA124 model from natural gas to propane.
Requirements
GA124 -17
70 MBtu/hr
GA124 -23
94 MBtu/hr
GA124 -30
123 MBtu/hr
WARNING!
This conversion kit must only be
installed by qualified heating contractor
as specified by the manufacturer’s
instructions and the applicable rules and
regulations of the local authorities. If
these instructions are not followed
exactly, a fire, explosion or release of
carbon monoxide may occur with
serious property damage or loss of life
and serious injury. The heating
contractor is liable for correct conversion
of the heating system with this
conversion kit.
CAUTION!
Before converting the heating system to
a different type of gas the gas line must
first be shut off and then the power to the
heating system must be disconnected.
Note: Please keep these instructions for future reference.

Contents
2Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
We reserve the right to make any changes due to technical modifications.
1Safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Correct use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Notes structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 Please observe these notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 Conversion to propane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4 Start-up instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.1 Making boiler ready for operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.2 Carrying out final commissioning tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Safety 1
3
We reserve the right to make any changes due to technical modifications.
Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
1 Safety
Observe these instructions for your safety.
1.1 Correct use
The conversion kit is used for conversion of the GA124
special gas-fired boiler from natural gas to propane.
1.2 Notes structure
Additional symbols for identification of dangers and user
instructions.
1.3 Please observe these notes
2 Scope of delivery
1. Honeywell gas solenoid valve conversion kit
# 393 691, comprising:
–black safety screw
–pressure adjustment screw
–red spring
–yellow label for gas fitting
2. BBR 12 ignition gas pilot orifice
3. main gas orifices and seals
4. unit label (to be filled out and attached to the unit)
5. Technical documents
WARNING!
RISK TO LIFE
Identifies possible dangers emanating
from a product, which might lead to serious
injury or death if appropriate care is not
taken.
WARNING!
RISK TO LIFE
from electric shock.
USER NOTE
Tip for the optimum utilization and setting
of the control(s) plus other useful
information.
WARNING!
RISK TO LIFE
from explosion of flammable gases.
Never work on gas lines unless you are
licensed for this type of work..
WARNING!
RISK TO LIFE
from electric shock.
Disconnect the power supply to the
heating system before conducting any
work on it, e.g. switch off the heating
emergency switch outside the boiler
room.
It is not sufficient just to switch off the
control.

4Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
We reserve the right to make any changes due to technical modifications.
Conversion to propane3
3 Conversion to propane
Read the instructions before conversion for your
safety.
The following instructions must be followed for
conversion of the boiler to propane:
1. If the boiler was in operation, close the gas shut-off
valve. Otherwise continue with step 3.
2. Disconnect system from the power supply and set
the thermostat to the lowest setting.
3. Remove safety screws from the left and right side
panels, then lift the front panel of the boiler and pull
it forward.
WARNING!
RISK TO LIFE
due to not observing the attached
conversion instructions.
If you wish to convert the boiler for
operation with propane, the conversion
from natural gas to propane must be
carried out first as specified by the
attached conversion instructions.
Fig. 1 Removing front panel of boiler

Conversion to propane 3
5
We reserve the right to make any changes due to technical modifications.
Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
4. Turn gas valve ON/OFF button clockwise to OFF
position. Do not use force.
Replacing main gas orifices
5. Disconnect pilot gas line from gas valve.
6. Disconnect ignition cable from ignition module.
Fig. 2 Gas valve
1ON/OFF button (at ON position)
1
WARNING!
RISK TO LIFE
from explosion of flammable gases.
Wait five (5) minutes until all gas
residues have dissipated. Check
whether there is any smell of gas,
including at floor level. If there is a gas
odor: STOP! Follow instructions in
section "B" of the safety instructions on
page 9 If there is no sign of a gas odor,
continue with the next step.
Fig. 3 Front view
1Flame roll-out switch (boiler size 17)
2Gas connection pipe
3Gas valve
4Ignition cable
5Ignition module
6Wire holder for gas supply line
7Aquasmart
8Pilot gas line
9Air supply hose
10 Gas supply pipe
11 Fuse
4
1
2
3
10
11
5
8
7
6
9
6 720 804 894-01.1T

6Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
We reserve the right to make any changes due to technical modifications.
Conversion to propane3
7. Remove the safety screw for the manifold pressure
adjustment on the gas valve.
8. Remove orifice pressure adjustment screw.
9. Remove stainless steel spiral spring.
10. Install the red spring from the Honeywell LP
conversion kit in the gas valve.
11. Screw in the new orifice pressure adjustment screw
from the Honeywell LP conversion kit until it is flush
with the top edge of the pressure adjustment.
Then screw the manifold pressure adjustment screw
six (6) revolutions clockwise. This sets the pressure
to about 10.0 in W.C. This setting must be checked
with a pressure gauge when the conversion is
complete.
12. Install new black safety screw from the Honeywell
LP conversion kit.
13. Clean the housing of the gas fitting (Fig. 4) and
attach the yellow label (Fig. 4) from the Honeywell
LP conversion kit to the gas valve in a conspicuous
position.
14. Tie gas line (Fig. 3, page 5) with wire or cord
(Fig. 3, page 5) (secure).
15. Remove screws between gas valve and burner box.
Place the gas connection pipe gasket in a safe
place.
16. Label wires of flame roll-out switch and disconnect
from the roll-out switch.
17. Remove screws in burner box cover and remove
cover.
18. Unscrew nuts and remove gas burner with burner
box.
19. Release air supply hose (Fig. 3, page 5) and pull
off burner box.
Fig. 4 Gas valve
1Safety screw
2Orifice pressure adjustment screw
3Stainless steel spiral spring
4Gas valve
5Yellow label
1
23
4
5
Fig. 5 Gas burner
1Fixing nuts
2Screws
3Flame roll-out switch (boiler size 23 and 30)
4Burner box cover
1
3
4
2
1
CAUTION!
RISK TO LIFE
due to incorrectly connected wiring.
When conducting maintenance work
label all cables before disconnecting
them.

Conversion to propane 3
7
We reserve the right to make any changes due to technical modifications.
Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
20. Turn gas burner 180° and unscrew bottom burner
box panel.
21. Install the new main gas orifices and copper
gaskets. Check with Tab. 1 that the correct
orifices for operation of the boiler are installed.
22. Screw bottom burner box panel into place again.
Replacing pilot gas orifice
23. Unscrew ignition pilot line from pilot burner.
24. Remove pilot orifice.
25. Place the new BBR 12 pilot orifice in the pilot burner.
26. Screw the pilot line to the pilot burner unit.
27. Check that the pilot burner unit is correctly seated
compared to the main burner.
28. Install gas burner in boiler in reverse order of
removal. Tighten the fixing nuts well.
Make sure that the front edge of the burner box
cover (Fig. 8, page 8) is properly engaged in the
sealing grommets (Fig. 8, page 8).
Fig. 6 Removing gas burner
1bottom burner box panel
1
Orifices sizes for propane
Model GA124 -17 GA124 -23 GA124 -30
Orifice size 175 160 160
Number 234
Tab. 1 Orifice sizes
USER NOTE
The orifice sizes are for installations
between 0 and 8500 feet above see level.
Follow the "Conversion instructions for
high altitudes" for installations between
8501 and 12000 feet above sea level.
Fig. 7 Pilot burner
1Ignition cable
2Pilot burner
3Main burner
4Pilot orifice
5Pilot gas line
1
4
3
2
5

8Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
We reserve the right to make any changes due to technical modifications.
Conversion to propane3
29. Tighten the screws (Fig. 5, page 6) between the
gas valve and the burner box again. Make sure that
the connection pipe gasket removed in step 15 is
replaced.
30. Attach wires to the flame roll-out switch.
31. Remove wire or rope that was used to hold the gas
supply line in step 14.
32. Connect pilot gas line to gas valve again.
33. Connection ignition wire to the ignition module.
34. Enter the required information on the conversion
label and attach on the outside of the boiler jacket as
close as possible to the nameplate.
Carrying out leak test
35. Open manual gas shut-off in the gas line.
36. Check the gas supply line to the gas valve for leaks
with soap solution. If no leaks are found, continue
with step 38. If any leaks are found, close gas
shut-off valve.
37. Seal leaks and repeat step 36.
38. Close main shut-off valve. Remove the screw plug
for the gas supply port on the gas valve. Install
pressure measuring nipple and attach a pressure
gauge to measure the gas pressure.
39. Remove the screw plug for the manifold pressure
port on the gas valve. Install pressure measuring
nipple and attach a pressure gauge to measure the
manifold pressure.
40. Open gas valve and measure the gas pressure of
the boiler. The connection pressure must be
between 11" and 13" W.C. If the connection
pressure is not between 11" and 13" W.C., contact
your customer service technician or LP gas
company.
41. Always follow the start-up instructions on the next
page.
Fig. 8 Front view
1Flame roll-out switch (boiler size 17)
2Gas connection pipe
3Gas valve
4Ignition cable
5Ignition module
6Wire holder for gas supply line
7Aquasmart
8Pilot gas line
9Air supply hose
10 Gas supply pipe
11 Fuse
4
1
2
3
10
11
5
8
7
6
9
6 720 804 894-01.1T
Fig. 9 Gas valve
1ON/OFF button (at ON position)
2Screw plug for gas supply pressure measuring port
3Screw plug for manifold pressure measuring port
4Pilot gas line connection
3
2
1
4

Start-up instructions 4
9
We reserve the right to make any changes due to technical modifications.
Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
4 Start-up instructions
Read the instructions before start-up for your
safety.
AThis unit is fitted with an igniter that automatically starts the
ignition burner. Do not attempt to ignite it manually.
BCheck for an odor of gas around the system. This test must
also be conducted at floor level, because some types of
gas are heavier than air and may accumulate at floor level.
CSwitch on the ON/OFF switch on the gas valve by hand
only. Never use a tool as assistance. If you cannot actuate
the ON/OFF switch on the gas valve by hand, do not
attempt to repair it. Contact a qualified technician. Any
attempt to use force or to repair the valve may cause a fire
or explosion.
DDo not operate the unit if any part is under water. Contact
a qualified customer service technician immediately to
have the unit checked and to replace the parts of the
control and gas fittings that were under water.
WARNING!
RISK TO LIFE
due to not observing the start-up
instructions and resulting incorrect
operation.
If these instructions are not followed
exactly, a fire or explosion may be
caused with serious property damage
or loss of life or serious injury.
Observe the start-up instructions.
WARNING!
DANGER OF EXPLOSION
If you smell gas there is a danger of
explosion..
No open flame. No smoking.
Prevent spark formation.
Do not operate electrical switches,
including telephones, plugs or door
bells.
Shut off main gas supply valve.
Open doors and windows.
Warn other occupants of the building.
Evacuate the building.
Call gas company or fire department
from outside the building.

10 Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
We reserve the right to make any changes due to technical modifications.
Start-up instructions4
4.1 Making boiler ready for operation
STOP! First read the safety instructions on page 9 of
this manual.
1. Carry out leak test (page 8). Wait five (5) minutes
until all gas residues have dissipated. Finally check
whether there is any smell of gas, including at floor
level. If there is a gas odor: STOP! Follow
instructions in section "B" of the safety instructions
on page 9 of this manual. If there is no sign of a
gas odor, continue with the next step.
2. Open main gas valve.
4.1.1 Placing heating system with aquasmart control in operation
The boiler is fully functional with the factory-installed
aquasmart.
3. Turn on ON/OFF switch (contractor installed) (ON
position). This turns on the boiler with all its
components. Then continue with step 7.
4. Make sure that the room thermostat signals a heat
requirement (set thermostat at least 10 °F above
room temperature).
4.2 Then carry out start-up procedures.
The following start-up procedures must be carried out
regardless of the control type.
5. Look at the igniter through the sight glass in the
burner housing.
Fig. 10 Switching on heating system (with aquasmart)
1ON/OFF switch (main switch)
1
Fig. 11 Front view
1Sight glass
1
6 720 804 894-02.1T

Start-up instructions 4
11
We reserve the right to make any changes due to technical modifications.
Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
6. Turn gas valve ON/OFF switch counterclockwise to
ON position.
7. The automatic igniter must generate sparks towards
the pilot burner. The pilot flame must appear and
then ignite the main burner. If the main burner does
not ignite, close the gas valve. Disconnect heating
system from the power supply and inform your
customer service technician or LP gas company.
8. If the main burner has ignited, the gas valve must be
checked for leaks with soap solution. If no leaks are
found, continue with step 12. If leaks have been
found, switch ON/OFF switch on gas valve
clockwise to the OFF position. Disconnect heating
system from the power supply and set the
thermostat to the lowest setting.
9. Seal leaks. Repeat steps 1 and 2 (regardless of the
control in use).
Caution:
With aquasmart control continue with steps 3 and 4.
Then repeat steps 7 to 10 regardless of the control
in use.
10. Check the supply gas pressure while the boiler is
operating. The supply pressure must be between
4.7" and 10.5" W.C. for natural gas and between 11"
and 13" W.C. for propane gas. Record the measured
values in the commissioning protocol in the
installation and maintenance instructions.
11. Check manifold pressure. The nozzle pressure must
be set in accordance with the values in Tab. 2. To
set the manifold pressure the cover (Fig. 12) on
the gas valve must be removed. Turn the adjustment
screw clockwise to increase the pressure and
counterclockwise to reduce the pressure. This
setting must be adjusted while the boiler is
operating.
12. Record the set value in the commissioning protocol
of the installation and maintenance instructions and
screw the safety screw (Fig. 12, page 11) into the
gas valve again.
Fig. 12 Gas valve
1ON/OFF button (at ON position)
2Screw plug for gas supply pressure measuring port
3Safety screw for manifold pressure setting
4Screw plug for manifold measuring port
5Safety screw for pilot ignition pressure setting
1
2
4
5
3
GA124 Natural gas
[inch W.C.]
Propane
[inch W.C.]
17 3.6 8.9
23 3.6 9.9
30 3.5 9.5
Tab. 2 Manifold pressure

12 Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
We reserve the right to make any changes due to technical modifications.
Start-up instructions4
13. Observe ignition flame through the sight glass
(Fig. 11, page 10) in the burner housing.
14. The flame must envelope the flame guard 1/2 to
1 1/2 inches. If this is the case continue with step 20.
15. If the ignition flame is too small or too large, the
pressure for pilot burner must be adjusted with the
corresponding adjustment screw.
16. Remove safety screw for pilot ignition pressure
setting (Fig. 12, page 11). Turn the inner
adjustment screw clockwise to reduce the ignition
flame and counterclockwise to enlarge the ignition
flame.
17. After adjustment tighten the ignition gas pressure
adjustment safety screw (Fig. 12, page 11) again.
18. Observe main burner flame through the sight glass
(Fig. 11, page 10) in the burner housing. The
flame must have a steady and fixed contour and
generally has a bluish color. If the main burner flame
meets the requirements, proceed with step 21. If the
main burner flame is too weak or is yellow or goes
out, turn the ON/OFF switch (Fig. 12, page 11) on
the gas valve clockwise to OFF. Close the gas valve
and disconnect the heating system from the power
supply and contact the customer service technician
or the gas company.
Checking flame sensor
19. Test the safety switch by closing the gas valve. The
main burner flame (Fig. 14) and the ignition flame
(Fig. 13) are extinguished. After six (6) seconds at
the most the main gas solenoid valve on the gas
valve must close with an audible noise.
20. After 90 seconds the automatic igniter must switch
to lock status and stop generating sparks.
21. Disconnect the heating system from the power
supply. Open main gas valve. Switch on unit power
supply. A normal operating cycle must follow.
22. If the gas valve operates correctly, proceed to
step 25. If the gas valve does not operate correctly,
switch ON/OFF switch (Fig. 15) on the gas valve
clockwise to the OFF position immediately. Close
main gas valve. Disconnect heating system from the
power supply and inform the customer service
technician or LP gas company.
Fig. 13 Correct pilot flame setting
11/2 to 1 1/2 inches
2Pilot flame
1
2
USER NOTE
The adjustment screw is behind the
ignition gas pressure adjustment safety
screw (Fig. 12, page 11).
Fig. 14 Main burner
1Main burner flame
1

Start-up instructions 4
13
We reserve the right to make any changes due to technical modifications.
Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
23. Turn gas valve ON/OFF button clockwise to OFF
position.
24. Close main gas shut-off.
25. Disconnect heating system from the power supply
and set the thermostat to the lowest setting.
26. Remove pressure measuring nipple and pressure
gauge for measuring gas supply pressure and
manifold pressure from the gas valve and close the
openings with the screw plugs.
27. Repeat steps 1 to 10 (depending on the control) and
20 to restart the heating system. Check the screw
plugs for leaks with soap solution. If no leaks are
found, continue with step 31. If leaks are found,
close gas shut-off and switch ON/OFF button on gas
valve clockwise to the OFF position. Disconnect the
heating system from the power supply.
28. Seal leaks. Open gas shut-off and repeat step 24.
29. Carefully wipe away the soap solution to prevent
corrosion caused by the alkali content of the soap.
30. Check the function of the maximum aquasmart to
make sure that it switches off the boiler as soon as
the boiler water temperature set at the aquasmart is
reached. Record the result in the commissioning
protocol of the installation and maintenance
instructions.
31. Replace front panel of boiler.
Fig. 15 Gas valve
1ON/OFF button (at ON position)
1

Notes
14 Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10
We reserve the right to make any changes due to technical modifications.

Notes
15
We reserve the right to make any changes due to technical modifications.
Conversion instructions Logano GA124 special gas-fired boiler • Issue 2012/10

Bosch Thermotechnology Corp.
50 Wentworth Avenue
Londonderry, NH 03053
Tel. [phone]
Fax [phone]
www.buderus.us
Products manufactured by
Bosch Thermotechnik GmbH
Sophienstrasse 30-32
D-35576 Wetzlar
www.buderus.com
Bosch Thermotechnology Corp. reserves the right
to make changes without notice due to continuing
engineering and technological advances.