Granby Conforto Series Setup guide

2021-3-1 G2020-E6 - Rev. C
Installation, Operation and
Service Manual
Conforto Boiler SERIES
B*C - 3 to 9 sections boiler
*Designates Brand Name
Three section boiler shown
INSTALLATIONS MUST MEET ALL LOCAL AND FEDERAL
CODES THAT MAY DIFFER FROM THIS MANUAL
Please read the manual in its entirety before beginning installation.
This manual must be kept with the boiler for future reference.
Manufactured by:
GRANBY FURNACES INC.
PO Box 637
12118 Hwy 209
Parrsboro Nova Scotia Canada, B0M 1S0
Distributed by:
GRANBY HEATING PRODUCTS, LLC.
67 Target Industrial Circle
Bangor, ME 04401
www.granbyindustries.com

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TABLE OF CONTENTS
Boiler – Oil
1.0 IMPORTANT SAFETY ADVICE ........................................................3
2.0 PRODUCT INFORMATION .............................................................4
3.0 UNIT INSTALLATION .....................................................................5
3.1 PLACEMENT & LEVELING OF THE UNIT ...........................................................................................................5
3.2 TRIM KIT COMPONENT INSTALLATION............................................................................................................5
3.3 JACKET ASSEMBLY AND CONTROL INSTALLATION ..........................................................................................7
4.0 PIPING.........................................................................................11
5.0 ELECTRICAL WIRING ...................................................................16
6.0 CHIMNEY INFORMATION ...........................................................19
7.0 FUEL SYSTEM ..............................................................................20
8.0 BURNER INSTALLATION AND SETTING .......................................21
9.0 TECHNICAL INFORMATION.........................................................24
10.0 BOILER START UP AND OPERATION ...........................................25
10.1 START UP PROCEDURE ................................................................................................................................25
10.2 HONEYWELL L7248 AQUASTAT ...................................................................................................................25
10.3 HYDROSTAT 3250 CONTROL........................................................................................................................26
11.0 MAINTENANCE / SERVICE...........................................................28
11.1 CLEANING THE BOILER ................................................................................................................................29
11.2 BURNER NOTES..........................................................................................................................................29
11.3 PERFORM COMBUSTION TEST...................................................................................................................29
12.0 EXPLODED PARTS VIEW.............................................................30
13.0 START-UP TEST RESULTS............................................................32

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1.0 IMPORTANT SAFETY ADVICE
Please read and understand this manual before installing, operating or
servicing the boiler.To ensure you have a clear understanding of the operating
procedures of the appliance please take the time to read the section IMPORTANT
SAFETY ADVICE in this manual.
CAUTION
DO NOT START THE BURNER UNTIL ALL FITTINGS, COVERS AND DOORS
ARE IN PLACE.
DO NOT TAMPER WITH THE BOILER OR CONTROLS, CALL A QUALIFIED
BURNER TECHNICIAN.
DO NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE VAPOURS AND
LIQUIDS IN THE VICINITY OF THIS UNIT OR ANY OTHER APPLIANCE.
NEVER BURN GARBAGE, PAPER OR ANY OTHER COMBUSTIBLE MATERIAL
IN THE UNIT, AND NEVER LEAVE COMBUSTIBLE MATERIAL AROUND IT.
ALWAYS KEEP A CLEAR SPACE AROUND THE APPLIANCE
IMPORTANT
This manual contains instructional and operational information for the OIL-FIRED
Boiler. Read the instructions thoroughly before installing the boiler or starting the
burner. Consult local authorities about your local FIRE SAFETY REGULATIONS.
All installations must be in accordance with local, state or provincial codes.
Improper installation will void the warranty.

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2.0 PRODUCT INFORMATION
PHYSICAL DIMENSIONS
No. of
Sections
Length
Weight
Shipping Weight
Water Content
Flue Size
(inches)
(pounds)
(pounds)
(us gal)
(inches)
3
18.5
275
310
6
5
4
23.0
338
379
7.5
5
5
27.5
401
447
9
5
6
31.75
464
515
10.5
6
7
36.25
527
586
12
6
8
40.5
590
654
13.5
6
9
45.0
653
722
15
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CLEARANCES
Proper clearances must be maintained not only from combustible materials but also to provide
adequate access for servicing. All installations must comply with local codes and CSA B139 and
NFPA 31.Consult local fire codes for required clearances.
CLEARANCE (minimum) FOR SERVICING
Top 10” (254 mm)
Front 24” (609 mm)
Rear 24” (609 mm)
Control Mounted Side (Left/Right) 24”(609 mm)
Non-Control Mounted Side (Left/Right) 6” (152 mm)
CLEARANCE (minimum) TO COMBUSTIBLES
Top 10” (254 mm)
Front 24” (609 mm)
Rear 24” (609 mm)
Control Mounted Side (Left/Right) 24” (609 mm)
Non-Control Mounted Side (Left/Right) 6” (152 mm)
Chimney Connector 18” (457 mm)
Floor must be non-combustible.
DRAFT PRESSURE
Breech draft pressure -0.015’’ w.c. draft required
Drafts in excess of -0.015” w.c. will require the installation of a barometric damper.

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TEMPERATURE DELTA: 20°F
FLUE PIPE CONNECTION
CHIMNEY or Granby Direct Vent System (3, 4 & 5 section boiler only)
CLEANOUTS
Rear removable smoke hood & front combustion chamber swing door
FUEL
Not heavier than No.2 fuel oil
CAUTION: Do not use gasoline, crankcase drainings, or any oil containing
gasoline.
ELECTRICAL
120 Volts, 60Hz, 15 amps. fuse or breaker
AIR SUPPLY
CAUTION: Adequate air supply for both combustion and ventilation must be available.
See page 20 for details.
3.0 UNIT INSTALLATION
The installation of the unit shall be in accordance with regulations of the authorities having
jurisdiction and be in accordance with CSA B139, NFPA31 and NFPA211.
3.1 PLACEMENT & LEVELING OF THE UNIT
The boiler should be located on a firm foundation in an easily accessible area that meets the
previously discussed clearances and air requirements. In situations where the floor may be
uneven the boiler may be leveled by the insertion of metal shims under the legs.
3.2 TRIM KIT COMPONENT INSTALLATION
If you purchased the “packaged” version of this boiler, the trim kit components and jacket have
been factory installed. Proceed to Section 3.2 – Step 8 – Control Mounting on page 11 of this
manual for remaining installation instructions.
If you purchased the “knockdown” version of this boiler, the trim kit components and jacket need
to be field installed following the instructions in sections 3.2 and 3.3.

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STEP 1: VERIFY CONTENTS OF TRIM KIT
The boiler trim kit package includes:
Knockdown Boiler Trim Kit Components
Item Part no. Description
Hydrolevel Kit
CBT-KD-3250-00
Honeywell Kit
CBT-KD-7248-00
Qty
Qty
1
CBF-BN-1025-00
1" x 2 1/2" Nipp
2
2
2
CBF-BT-1010-07
1" x 1" x 3/4" Tee
2
2
3
CBF-BP-0010-00
1" Plug
2
2
4
CBA-BD-0852-07
Drain
1
1
5
CBA-34-MPRV-00
Pressure Relief Valve
1
1
6
CBA-00-TRID-20
T&P Gauge
1
1
7
CBA-48-2010-00
3/4" Well
1
1
8
CBA-48-3250-58
Thermistor 48"
1
NA
9
CBA-48-3150-50
Grommet
1
1
10
CBA-48-102A-00
Remote Mount Kit
1
NA
11
CBA-48-3250-00
Hydrostat 3250 Plus
1
NA
12
CBA-HW-7248-00
Honeywell L7248
NA
1
13
CBA-HW-5001-48
Honeywell 48” Thermistor
NA
1
Package Boiler Trim Kit Components
Item Part no. Description
Hydrolevel Kit
CBT-PK-3250-00
Honeywell Kit
CBT-PK-7248-00
Qty
Qty
10
CBA-48-102A-00
Remote Mount Kit
1
NA
11
CBA-48-3250-00
Hydrostat 3250 Plus
1
NA
12
CBA-HW-7248-00
Honeywell L7248
NA
1
13
CBA-HW-5001-48
Honeywell 48” Thermistor
NA
1
STEP 2: INSTALL TRIM COMPONENTS
Knockdown Boiler trim items 1-7 should be installed now, prior to system piping & casing
installation. The remaining items and the Package Boiler trim items will be installed during later
steps in the manual. All threaded connections require the application of a high quality pipe thread
sealant.

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3.3 JACKET ASSEMBLY AND CONTROL INSTALLATION
The boiler jacket has been designed for ease of assembly and removal. The following are step
by step instructions. A philips screwdriver, 17mm socket and ratchet, 17mm wrench or
adjustable wrench are needed.
STEP 1: VERIFY CONTENTS OF JACKET ASSEMBLY PACKAGE.
Your jacket assembly will contain boiler block insulation, rear of block insulation, front panel
insulation, two (2) side panels, rear panel, top panel, front panel and a fastening package with
screws and foil tape for fastening insulation. See jacket content photos below.
NOTE: If you are installing a 7, 8, or 9 section boiler, the jacket will be supplied in
two boxes. Box 1: 4, 5, or 6 section boiler jacket (respectively). Box 2: rear jacket extension
which includes a top, two (2) side panels, block insulation and additional fastening screws.

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STEP 2: INSULATION INSTALLATION
Drape the large piece of boiler block insulation directly over the block taking care to provide equal
coverage on both sides. If installing a 7,8, or 9 section boiler, the extension insulation
should be draped over the rear 3 sections of the boiler. Install the rear insulation piece by
sliding it over the upper tie rods and around the flue collar as shown. Secure the rear insulation
to the boiler block insulation using the foil tape provided.
STEP 3: REAR PANEL INSTALLATION
Remove the four nuts from the rear of the tie rods. Slide the rear panel onto the tie rods until it
sits flush against the spacers. Re-install the nuts. Tighten the nuts to secure the rear panel.
STEP 4: SIDE PANEL ATTACHMENT
Remove the four nuts and washers from the front of the tie rods.

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STEP 4: SIDE PANEL ATTACHMENT CONTINUED
Align the left and right panel so the knock out on the side of each panel is located toward the
upper front corner of the boiler. Install each side panel by sliding the front mounting holes over
the front tie rods. The back of the side panel can then be slid over the rear panel. If installing a
7,8, or 9 section boiler, the extension side panels must be screwed to the boiler side
panels prior to mounting. Make sure the slotted holes on the extension side panels are
facing toward the back of the boiler.
Re-install the washers and nuts on the front tie rods and tighten. Secure the back of the side
panels to the rear panel with the sheet metal screws provided.
STEP 5: CONTROL SENSOR ATTACHMENT
Prior to jacket top and front panel installation the control sensor must be routed through the side
panel knock out. The boiler operating control can be mounted on either side of the boiler. Once
the control mounting side has been selected, remove the corresponding knockout, install the
plastic sensor protector and feed the sensor wire through the hole. Route the sensor wire over
the boiler insulation to the immersion well in the top rear section of the boiler. Make sure the
sensor bulb is fully inserted into the brass well and secure with the grommet provided.

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STEP 6: TOP PANEL ATTACHMENT
Affix the top panel by placing the holes located on the underside of the panel over the jacket
affixing pins. Press down on the top panel and it will snap in place. Secure the top panel to the
back of the side panels with 2 sheet metal screws provided in the hardware packet. If installing a
7,8, or 9 section boiler, the extension top panel will be mounted in the same way.
STEP 7: FRONT PANEL ATTACHMENT
Align the front panel pins with corresponding side panel clips. Push the front panel toward the
boiler and pins will snap into the clips. Be sure to engage all four pins on the front panel.
The jacket installation is now complete.

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STEP 8: CONTROL MOUNTING
Upon completion of the jacket assembly the operating control can be mounted on the side
of the boiler where the sensor wire was installed. The jacket side panels have been pre-
drilled holes for mounting the control. Follow the mounting instructions and use the hardware
provided with the control.
Three section boiler illustrated
The boiler is now ready for piping and connection to the fuel system, heating and
domestic hot water, thermostat and 120 Volt 60 cycle AC current.
CAUTION: Safety relief valve discharge should be piped downward to within 6” of
the floor or to a drain. The valve must be mounted in a vertical position.
4.0 PIPING
Prior to connecting the boiler to an existing piping system, certain procedures must be followed.
The system must be flushed to ensure that scale and sludge will not be introduced to the boiler.
This is a must when replacing a boiler in what was once an open gravity system.
The Conforto boiler is a low mass boiler with low water content and steps must be taken to
ensure that the boiler is not inundated with cold return water from an existing high-volume
standing cast iron system. If the boiler is installed in a high-volume system a bypass loop must
be installed.
Manual shut off valves must be installed on both the supply line and on the boiler bypass loop.
Bypass loop piping MUST be the same size as the supply and return piping. ASME Boiler Code
requires that feed or make-up water be introduced to the piping system and not directly into the
boiler. Pressure reducing valve should be installed and adjusted to 12 psi cold water. The
pressure relief valve must be piped from the boiler and downward to within 6” of the floor or to a
height to meet existing code. An expansion tank, circulating pump and automatic air eliminators
must be part of the system. The relief valve, backflow preventer and drain valve should be piped
to a drain with piping that is the same size as the relief valve outlet, according to code.
All piping, including heating, domestic hot water and fuel lines must be done in accordance with
all local codes. It is suggested that you refer to the Water Installation Survey and Hydronic
Institute Residential Hydronic Heating Installation/Design Guide. All piping must be properly
sized, free from defect and be made of copper, steel, brass, aluminum or PEX.

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Circulation Pump
A calculation for proper pump selection must be performed for all installations. The pump(s)
should not be operated at maximum working pressures above 30 psi or maximum working
temperatures above 200°F and within limits advised by the manufacturer. The pump must not be
operated unless the system has been flushed, bled of all air and completely filled with water.
Recommended locations for the circulator, expansion tank, relief valve and other trim are
shown in Figures 1 - 7.
Figure 1: A typical installation with no domestic hot water and no by-pass
loop installed.

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Figure 2: A typical installation with no domestic hot water and with a by-pass
loop installed. By-pass MUST be same size as supply / return pipes.
Figure 3: A typical installation with domestic hot water supplied by an
indirect heater and with no by-pass loop installed.

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Figure 4: A typical installation with domestic hot water supplied by an
indirect heater connected to boiler accessory tappings.
Figure 5: A typical installation with domestic hot water supplied by an
indirect heater connected to boiler accessory tappings and a by-pass on
the heating circuit. By-pass MUST be same size as supply / return pipes.

15
Figure 6: Primary / Secondary piping with domestic hot water supplied by
an indirect heater connected to boiler accessory tappings.
Figure 7: Alternative Primary / Secondary piping with domestic hot water
supplied by an indirect heater connected to boiler accessory tappings.

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HEATING ONLY – No Indirect Water Heater
5.0 ELECTRICAL WIRING
All external wiring must be performed in compliance with existing electrical codes within the local
jurisdiction. In Canada, in compliance with the requirements of CSA STANDARD C22.1 and the
Canadian Electrical Code. In the USA, in compliance with the requirements of NFPA 70, National
Electrical Code. Connections should be carried out in accordance with this manual and only by
qualified individuals.
•The boiler and burner should only be operated on 120 Vac.
•Field connections should be properly sized and protected with a minimum 15A fuse or circuit
breaker.
•A separate fused disconnect must be installed as required by code so that power can be shut
off for servicing.
•The boiler must be grounded to the main service ground.
The connections must be made in a manner to ensure that there is no crossing of the neutral with
the phase, a proper ground is provided, and all three wires are connected to the operating
control.
Typical wiring for line voltage oil burner with Fuel Smart HydroStat 3250 and
one heating zone
CHOOSE OR BELOW
Connect thermostat or end switch from zone relay or multi-zone
panel to
T-T. Connect circulator to C2-C1. Move Zone/Indirect
Switch up to Z.
SINGLE CIRCULATOR
ZONE/
INDIRECT
SWITCH
POSITION
Connect end switch from circulator relay or multi-zone panel to
MULTIPLE CIRCULATORS
ZONE/
INDIRECT
SWITCH
POSITION

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Connect thermostat or end switch from zone relay or multi-zone panel
to
T-T. Connect circulator to C2-C1. Connect end switch from indirect
zone relay to
ZC-ZR. Move Zone/Indirect Switch down to I.
SINGLE CIRCULATOR
ZONE/
INDIRECT
SWITCH
POSITION
Connect end switch from heating circulator relays or multi-zone panel
to
T-T. Connect end switch from indirect circulator relay to ZC-ZR.
Move Zone/Indirect Switch to I.
MULTIPLE CIRCULATORS
ZONE/
INDIRECT
SWITCH
POSITION
HEATING and Indirect Water Heater
NOTE: The wire from ZR to the hot terminal of the indirect circulator will ensurethat
indirect calls will fire to limit and receive priority over heating calls.
MULTIPLE CIRCULATORS — Typical Zone Panel with Priority Zone
ZONE/
INDIRECT
SWITCH
POSITION
IMPORTANT: When installing with an indirect water heater, the Zone/Indirect Switch must be set in the I position. When set in the I position, calls to ZC-ZR will bypass
the Thermal Targeting feature and allow the boiler to fire to the high limit setting to heat the indirect tank. The indirect signal must be separate from all heating zone
signals. If you choose not to separate the indirect signal from the heating zones, the Economy Feature should be turned OFF to ensure that the boiler supplies
adequate temperature to heat the indirect tank (see page 7).
CHOOSE FROM THROUGH BELOW

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Typical wiring for line voltage oil burner with Honeywell L7248 and one
heating zone.
Make sure sensor is inserted ALL THE WAY into the immersion well on top of the
boiler. Route sensor wire through clearance hole A and connect it to the L7248 control.

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6.0 CHIMNEY INFORMATION
Natural Draft Applications
CAUTION: Oil fired units must always be connected to flues with sufficient draft.
Specific guidelines should be followed to prevent the occurrence of the following conditions:
•Reverse flow of flue gas during or after burner shutdown.
•Positive outlet draft conditions.
•Condensation of flue gasses
•Damage to masonry chimney
Chimney Connection
To insure safe and efficient boiler operation flue gasses must be released through a clean,
properly sized chimney with adequate draft that meets all local codes and regulations and be in
accordance with CSA B139, NFPA31, NFPA211 and local regulations. Always inspect and clean
the chimney to ensure that it is free from obstructions. Never connect the boiler to a chimney or
liner serving an open fireplace.
A 5” diameter flue pipe must be used for connection of the 3,4,5, section boiler flue outlet to the
chimney for the entire length of the connection. A 6” diameter flue pipe must be used for
connection of the 6,7,8,9, section boiler flue outlet to the chimney for the entire length of the
connection. The chimney connector must be made with the proper gauge thickness and diameter
of fluepipe as required by CSA B139, NFPA31, NFPA211, and local codes, be properly
supported and use as few 90 degree turns as possible. The distance between the boiler and the
chimney depends on whether or not elbows are used. The distance should be at least 24” if no
elbows are used and 12” if elbows are used. The same holds true for the maximum length of the
flue pipe. It must be no longer than 10’ if no elbows are used and 6’ if elbows are used.
Drafts in excess of -0.015” w.c. will require the installation of a barometric damper.
Condensation
The Conforto boiler series is a high efficiency boiler and as a result improper venting can lead to
condensing temperatures in the chimney connector and the venting system. If condensing
temperatures of below 325 Degrees F are reached in the chimney connector, then additional
steps to ensure proper draft must be taken. Make sure that all joints are properly sealed with a
high temperature silicone or mastic. If after sealing the joints the condition still exists, then
inspect the chimney for suitability. If the masonry, brick, block chimney or tile chimney liner is in
poor condition a new chimney liner rated for oil may have to be installed. In the event the
condition still exists after installation of a new liner consult Granby.

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7.0 FUEL SYSTEM
The fuel system piping must comply with the fuel pump manufacturers’ specifications which are
included with the burner. In addition, all fuel system piping must comply with local codes and
ordinances.
•The quality of your fuel oil is of great importance. For most instances your burner is
designed to burn clean, water free, #2 fuel oil.
•The oil supply line should be constructed of seamless heavy wall copper tubing with flared
fittings. Only oil resistant pipe dope should be used on threaded connections. The use of
Teflon Tape will void manufacturers’ warranty. Lines must be airtight, clean and free of
kinks. All joints and threaded fittings must be checked for leaks. A vacuum gauge should be
employed when testing the installation. It is recommended that older fuel lines be replaced.
•A two-pipe system should only be used when the oil supply is well below the pump. A return fuel line
may be used on inside installations where the tank level is below the level of the burner. The return
line must be equal in diameter to the suction line. The minimum size for the oil line is 3/8” copper
tubing. Do NOT install any valve in the return line.
•An oil de-aerator is recommended when the oil tank is located 5’ or more below the burner.
•Shut off valves must be installed in the supply line at or near the oil storage tank and at the burner in
compliance with all codes. Inspect the shut off valve spindle packing for tightness to ensure that
there are no air leaks. The burner should be tagged to indicate that the fuel supply has been closed
off. The electrical circuit to the burner must be cut off by removing the fuse or circuit breaker to
ensure that no operation of the burner will occur while the fuel supply is shut off.
CAUTION: ALWAYS KEEP THE OIL SUPPLY VALVE SHUT OFF IF THE BURNER IS SHUT
DOWN FOR AN EXTENDED PERIOD OF TIME.
•Only certified fuel storage tanks and accessories approved as prescribed by local code may be used.
•The installation of 2, 10 micron oil filters, one at the tank and the other at the burner is recommended.
•Automatic oil safety valves (O.S.V. / P.R.V.) are recommended to provide automatic shut-off for the oil
supply incase the line between O.S.V. device and burner fuel pump is broken or damaged.
OIL TANK AND PIPING
Draft
regulator
O.S.V.
or
P.R.V.
Shut off