Slant/Fin Prodigy 21 KC-45 User manual

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Gas-fired • Cast-iron • Hot Water Boilers
Sealed Combustion — Direct Vent
WALL MOUNT
HOT WATER BOILER
INSTRUCTION MANUAL
Contents...............................................Page
•Planning Ahead .........................................2
•Installation Procedures..............................4
•Operation Procedures .............................12
•Maintenance Procedures ........................15
•Troubleshooting .......................................16
REFERENCES FOR YOUR USE
Boiler Failure Codes.....................................................16
Boiler Location Requirements .......................................2
Blower Speed Calibration ...........................................13
Components Identification ............................................2
Data (Boiler) ..................................................................3
Diagnostic Indicator Light ...........................................16
Dimensions ...................................................................3
FreezeProtection.........................................................15
Gas Valve Calibration...................................................13
Indicator Light Panel ...................................................12
Input Rate Verification Procedure ...............................13
Jacket Installation ........................................................11
Lighting Instructions ....................................................20
Measuring Equipment ..................................................12
Orifice (Gas and Air) Sizes .........................................24
Purge Heating System ..................................................9
Replacement Parts .....................................................15
Safety Controls.............................................................14
Sequence of Operation ...............................................21
Thermostat Heat Anticipator .......................................11
Venting Location Requirements ....................................2
Water Treatment ..........................................................15
Wiring Diagram (Boiler) ..............................................22
Models KC-45 and KC-90
Boiler Packing List
SEE BACK PAGE OF THIS MANUAL
Additional Tools Needed
• Differential pressure gage: 0 - 1.0" w.c. range with
.02" increments.
•Plastic gage hookup tubing: 2 lengths of 3/16" I.D.
tubing with female service fitting adapters.
•Microampmeter: 0-25 microamp range with
1microamp increments.
Printed in USA 100 PUBLICATION P-40
Part No. 65-0646 Rev. G
This manual must be left with owner, hung on or
adjacent to the boiler. Owner should retain
manual for future reference.
®

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PART 1: PLANNING AHEAD
Circulator, ASME #30 pressure relief valve and automatic air vent are factory mounted/wired. Low water cutoff is
factory-installed. Low water cutoff will shut off boiler in the event water falls below lowest safe water level.
BOILER LOCATION REQUIREMENTS
Boiler must be wall-mounted and can be installed on
acombustible wall. Boiler must be mounted on a
wall which provides access to the outside for choice
of venting. Boiler must not be installed on or above
carpeting.
Wall through which venting will pass must be free
and clear for opening (i.e. no hidden conduit, tele-
phone cables or other obstructions). Wall construc-
tion must be able to support the weight of boiler, pip-
ing and fill water.
For a closet installation, ventilation openings must be
provided through a door or wall to prevent excessive
heat buildup. Two openings, one near the floor and
one near the ceiling, should be sized to assure suffi-
cient air circulation in the closet (minimum 100 sq.
inches each).
Boiler must be installed so gas ignition system com-
ponents are protected from dripping or spraying
water or rain during operation and service.
VENTING LOCATION REQUIREMENTS
Vent installations shall be in accordance with Part 7,
Venting of Equipment, of the National Fuel Gas
Code,ANSI Z223.1, or applicable provisions of local
building codes.
The boiler can be vented directly through a rear wall
or through anywall within 10 feet of the right side,
left side or backof the boiler. Venting is approved for
wall thickness of 4" to 24". The boiler cannot be vent-
ed up through a roof.
Maximum vent pipe length for both the exhaust and
air intake is 10 feet external to boiler with no addi-
tional elbows other than those provided with boiler.
Vent termination must meet the following clearances:
Minimum of 12" above grade and normal snow line to
vent terminal bottom; minimum of 12" from any
building opening; minimum of 3 feet above any forced
air intake located within 10 feet; minimum of 4 feet
from electric or gas meters, regulators and relief
equipment.
Vent termination must not be located over any public
walkway, in any confined space (i.e. window wells,
alcoves, narrow alleys) or under any overhang or
deck. Vent termination should not allow flue-gas dis-
charge towards neighbor’s windows or where person-
al injury or property damage can occur.
Vent terminal is designed to deflect flue gases from
outside building wall; properly installed, it will prevent
flue-gas degradation of normal building materials.
DO NOT install the venting into a chimney or any
common venting system. DO NOT install a vent
damper or similar device in vent tubing or on the boiler.
Vent terminal provided by Slant/Fin must be used.
This vent terminal must only be mounted to an out-
side vertical wall.

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Minimum Clearances
ToCombustibles
and Recommended
Service Clearances
Minimum Service
Front 6" 18"
Sides 2" 12"
Top 3" 3"
Bottom 12" 12"
Rear 0" 0"
Flue Conn.* 1-1/2" 3"
Boiler Heat Exchanger
Water Content
Model Water Content
KC-45 1/2 gal.
KC-90 1gal.
* Flue tubing must be insulated
with supplied insulation materi-
al for wall passage.
KC-45 45 22.5 9 3.5 14 11 141⁄248
1⁄241⁄291⁄233⁄4220
KC-90 90 45 9 3.5 14 11 171⁄2711
1⁄271⁄2121⁄261⁄4280
Boiler
Model
Gas Input
(MBH)
Gas Pressure (In. w.c.)
Dimensions (In.)
Natural Propane
High Low Max. Min. Max. Min. A B C D E F
Shipping
Weight
(lbs)
NOTICE: INSTALLATION AND SERVICE
MUST BE PERFORMED BY A
TRAINED AND QUALIFIED TECHNICIAN.
The installation must conform to the require-
ments of the National Fuel Gas Code ANSI
Z223.1 and the requirements of the authority
having jurisdiction as well as the requirements
in this instruction manual.
In addition, where required by the authority
having jurisdiction, installation must conform to
the Standard for Controls and Safety Devices
for Automatically Fired Boilers, ANSI/ASME
CSD-1. If there is any conflict in the above
requirements,then the more stringent require-
ment will apply.
WARNING
LIQUEFIED PETROLEUM (L.P.) PROPANE GAS-FIRED
BOILER LOCATION
REQUIRES SPECIAL ATTENTION
Liquefied Petroleum (L.P.) propane gas is heavier than air.
Therefore, propane boilers, piping, valves must NOT be installed
in locations where propane leaking from defective equipment
and piping will "pool" in a basement or other space below the
leak.
Aspark or flame from the boiler or other source may ignite the
accumulated propane gas causing an explosion or fire. Location
should be as near the vent terminal as possible so that the flue
pipe from boiler to outside is short and direct.
The UNIFORM MECHANICAL CODE may be in effect in your
geographic area.
The following precautions are cited by the 1994 UNIFORM
MECHANICAL CODE, section 304.6:
"LPG Appliances. Liquefied petroleum gas-burning appli-
ances shall not be installed in a pit, basement or similar
location where heavier-than-air-gas might collect.
Appliances so fueled shall not be installed in an above-
grade under-floor space or basement unless such location is
provided with an approved means for removal of unburned
gas."
Consult Chapter 5 of the 1994 UNIFORM MECHANICAL CODE
for design criteria of the "approved" means for removal of
unburned gas.

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PART 2: INSTALLATION PROCEDURES
Boiler can be mounted on and vented directly through
an outside rear wall or mounted on an interior wall and
vented through an outside rear wall that is within 10 feet
of the back of the boiler. See Figure on Page 3.
If horizontal passage through wall is aboveboiler, vent
tubing can be extended vertically from boiler to reach
horizontal passage; full tubing length must still be within
10 feet external to boiler with no additional elbows.
If wall is frame construction, locate wall studs for mount-
ing. Suggested boiler mounting height is 32" minimum
from floor to bottom of boiler enclosure. This allows for
ease of service and/or the installation of an indirect-
fired water heater under boiler.
1. Hold mounting panel on wall (with the boiler mount-
ing studs facing out) in the location where boiler will
be positioned and level wall panel.
2. Mark the mounting bolt holes for wall panel on wall.
Use the cutout in the top of the mounting panel to
mark 9"x5" rectangular vent cutout on wall.
3. Drill mounting bolt holes for wall panel. Cut the
9"x5" opening through rear wall and do all finishing
work.
4. Secure the mounting panel (see Figure 1) to wall
using appropriate hardware: 5/16" lag bolts (provid-
ed) for frame construction wall studs; 5/16" wall
anchors or expansion plugs if construction is other
type.
5. For extended rear-wall venting only, follow the
boxed instructions above.
6. Place hex nuts (provided) loosely on the ends of
boiler mounting studs on mounting panel. (See
Figure 2.) Two keyhole-shaped slots are provided
on each side of the boiler rear which allow hex nuts
(on studs) to pass through slots. Lift the boiler and
seat it on the mounting studs. Tighten hex nuts
securely.
STEP 1A: MOUNTING BOILER WITH REAR WALL VENTING
Figure 1: Secure Mounting Panel Figure 2: Position and Secure Boiler
How To Locate Outside Wall Opening
For Extended Rear-Wall Venting
Remember, the maximum vent length is 10 feet
external to boiler with no additional elbows.
Measure the distance from floor or ceiling (whichev-
er is most level to the outside rear wall) to the center
of the vent opening.
Measure the same distance on outside rear wall
through which venting will pass. From this point,
drop the center mark 1/4" for every 1-foot of tubing
run from boiler. (Prevents condensate from flowing
back to boiler.)
Mark and cut 9"x5" opening through outside rear
wall around new center mark and do all finishing
work.

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Stainless Steel
Exhaust Tubing
Copper
Air Intake
Tubing
Exhaust
Outlet
Air Intake
Inlet
1 3/4" Beyond
Both Tubes
Must
Terminate
Surface.
1 3/4"
Figure 3: Rear Wall Vent Tubing Installation
Figure 4: Copper Parts Assembly
11 3/8" Vertical Riser
Figure 5: Insulation Installation
EXHAUST/AIR INTAKE TUBING
Vent installations shall be in accordance with Part 7,
Venting of Equipment, of the National Fuel Gas Code,
ANSI Z223.1, or applicable provisions of local building
codes.
Only 2" stainless steel tubing provided by Slant/Fin
Corp. can be used for exhaust venting. 2" copper DWV
tubing for air intake can be provided from Slant/Fin or
local supplier. See Figure 3.
7. For exhaust, install the stainless steel elbowed
tubing length (provided) on the boiler exhaust out-
let, pointing toward the outside wall opening.
8. For air intake, assemble copper tubing parts (see
Figure 4) provided with boiler and install assembly
on boiler air intake inlet, pointing toward outside
wall opening.
9. For extended rear-wall venting only, complete both
of the tubing runs through outside rear wall open-
ing. Avoid routing tubing internal to walls or ceil-
ings; always allow sufficient access to tubing for
annual inspection.
10. Both tubing runs must terminate exactly 1-3/4"
beyond outside wall surface for proper insertion
into vent terminal. If necessary, cut tubing to prop-
erlength and remove all burrs.
11. Seal all tubing run joints and boiler connections
with high-temperature RTV sealant (provided).
APPLY SEALANT TO OUTSIDE OF MALE TUBE
ENDS ONLY, 1/4 inch from the tube end, not
inside of tubes or fittings.
12. If vent length exceeds 5 feet, install one vibration
isolating-type hanger on each tubing run (to pre-
vent sagging).
13. Install the insulation (provided) around stainless
steel vent pipe and secure. Insulation must cover
the vent pipe passing through the wall and termi-
nate at outside wall surface.
14. Proceed to Step 2 on Page 8.

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STEP 1B: MOUNTING BOILER WITH SIDE WALL VENTING
Figure 6: Secure Mounting Panel Figure 7: Position and Secure Boiler
Boiler can be vented through an outside wall that is
within 10 feet right or left of the boiler with no addition-
al elbows.
If horizontal passage through wall is aboveboiler,vent
tubing can be extended vertically from boiler to reach
horizontal passage; full tubing length must still be with-
in 10 feet external to boiler with no additional elbows.
If wall is frame construction, locate wall studs for
mounting. Suggested boiler mounting height is 32"
minimum from floor to bottom of boiler enclosure. This
allows for ease of service and/or the installation of an
indirect-fired water heater under boiler.
1. Hold mounting panel on wall (with the boiler
mounting studs facing out) in the location where
boiler will be positioned and level wall panel.
2. Mark mounting bolt holes for wall panel on wall and
then drill mounting bolt holes for wall panel.
3. Secure the mounting panel (see Figure 6) to wall
using appropriate hardware: 5/16" lag bolts (provid-
ed) for frame construction wall studs; 5/16" wall
anchors or expansion plugs if construction is other
type.
4. Measure the distance from floor or ceiling (whichev-
er is most level to the outside side wall) to center of
9"x5" vent cutout on the wall panel.
5. Measure the same distance on the outside side wall
through which the venting will pass. This mark must
be5-1/2" from corner where the two walls adjoin.
6. From this point, drop the center mark 1/4" for every
1-foot of tubing run from boiler. (Prevents any con-
densate from flowing back to boiler.)
7. Mark and cut 9"x5" opening through the outside
side wall around new center mark and do all finish-
ing work.
8. Place hex nuts (provided) loosely on the ends of
boiler mounting studs on mounting panel. (See
Figure 7.) Two keyhole-shaped slots are provided
on each side of the boiler rear which allow hex nuts
(on studs) to pass through slots. Lift the boiler and
seat it on the mounting studs. Tighten hex nuts
securely.
EXHAUST/AIR INTAKE TUBING
Vent installations shall be in accordance with Part 7,
Venting of Equipment, of the National Fuel Gas Code,
ANSI Z223.1, or applicable provisions of local building
codes.
Only 2" stainless steel tubing provided by Slant/Fin
Corp. can be used for exhaust venting. 2" copper
DWV tubing for air intake can be provided from
Slant/Fin or local supplier.
9. For exhaust, install the stainless steel elbowed tub-
ing length (provided) on the boiler exhaust outlet,
pointing toward outside wall opening.

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10. For air intake, assemble copper tubing
parts (see Figure 9) provided with boiler
and install the assembly on boiler air
intake inlet, pointing toward outside wall
opening.
11. Complete both tubing runs through out-
side side wall opening. Avoid routing tub-
ing internal to walls or ceilings; always
allow sufficient access to tubing for
annual inspection.
12. Both tubing runs must terminate exactly
1-3/4" beyond the surface of the outside
wall for proper insertion into vent termi-
nal. If necessary,cut the tubing to proper
length and remove all burrs.
13. Seal all tubing run joints and boiler con-
nections with a high-temperature RTV
sealant (provided). APPLY SEALANT TO
OUTSIDE OF MALE TUBE ENDS ONLY,
1/4 inch from the tube end, not inside of
the tubes or fittings.
14. If vent length exceeds 5 feet, install one
vibration isolating-type hanger on each
tubing run (to prevent sagging).
15. Install the insulation (provided) around
stainless steel vent pipe and secure.
Insulation must cover the vent pipe pass-
ing through the wall and terminate at
outside wall surface.
Figure 9: Copper Parts Assembly
Figure 8: Side Wall Vent Tubing Installation
Figure 10: Insulation Installation

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STEP 2: INSTALL OUTSIDE VENT TERMINAL
Figure 11: Wall Plate Installation Figure 12: Vent Terminal Box Installation
VENT TERMINAL INSTALLATION
Warning: The vent terminal provided must be used.
DO NOT alter this part in any manner other than as
shown in these instructions. This vent terminal can
only be mounted on a vertical surface.
1. Checking tubing installation
a) Both exhaust and air intake tubes should extend
1-3/4” beyond outside wall surface.
b) Insulation on exhaust tube should be flush with
outside wall surface.
2. Check tubing orientation
a) Air inlet tubing may be located to the left or to
the right of the exhaust tube, depending on
which direction the tubes were run from the boil-
er.
b) If the air inlet tubing is to the left of the exhaust
(viewed from outside of building), then the vent
terminal may be installed as supplied without
alteration.
c) If the air inlet tubing is to the right of the exhaust
(viewed from outside of building), then the air
inlet cover must be removed and reinstalled over
the slots on the opposite side of the vent termi-
nal. This alteration will ensure that the air inlet
openings will face down when the vent terminal
is installed.
3. Prepare outside wall
a) Position vent terminal up to wall cutout so that
both exhaust and air intake tubes are inserted
into the terminal’s back openings.
b) Check that the wall mounting plate overlaps the
wall passage cutout on both sides for proper
sealing to wall.
c) Check that the terminal itself is level and that its
position ensures a 1/4” per foot downward pitch
of the tubing from the boiler.
d) Mark and drill out the location of the four screw
holes in the wall for mounting the vent terminal.
4. Install wall mounting plate
a) Separate wall mounting plate from vent terminal
box by unscrewing the two screws on both sides
of the terminal.
b) Run a bead of silicone around the inside perime-
ter of the back of the wall plate.
c) Slide the wall plate over the tubes and screw it
securely to the outside wall. Check that the plate
is flush and sealed to the wall around its perime-
ter.
d) Run a bead of RTV high-temperature sealant
around the tubes, both where they pass through
the wall plate and also about 1/4” from the end of
each tube for sealing the vent terminal box in the
next step.
5. Install vent terminal box
a) Place the vent terminal box over the tubes and
reattach to the wall mounting plate with the
screws removed in step 4.
b) Makesure the terminal is orientated so that the
air intake tube inserts into the side of the termi-
nal with the air intake openings, and that these
openings face downward and the air intake cover
is facing upward.
c) Make sure that both the air intake and exhaust
tubes insert into the vent terminal box and are
sealed properly.
RUN BEAD OF SILICONE
AROUND INSIDE PERIMETER
ON BACK OF WALL PLATE.
EXHAUST TUBE
SEPARATE WALL PANEL
FROM VENT TERMINAL BOX
BYREMOVING SCREWS.
AIR INLET
TUBE
INSULATION
WALL
P
ASSAGE
CUTOUT
AIR INLET COVER
( FACES UP )
AIR INLET OPENINGS
(FACE DOWN )
EXHAUST TUBE
AIR INLET TUBE
SILICONE
BEADS

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STEP 3: INSTALL EXPANSION TANK AND WATER PIPING
Expansion
Tank
Tank
Support
Bracket
Expansion
Tube
Tank Strap
Relief
Valve
Discharge
Supply
Water
Outlet
3/4"NPT
3/4"NPT
Return
Water Inlet
3/4"NPT
Return
Drain Valve
For Boiler
Supply
Shutoff
Valves
Pressure
Reducing
(Fill) Valve
Shutoff
Valve
Valves
Zone
Figure 14:
Expansion
Tank and
Piping
Connections
Note: Factory-
installed low
water cutoff
will shut off
boiler in the
event water
falls below the
lowest safe
water level.
Always follow good piping practices. Observe minimum
1" clearance to combustibles around all uninsulated hot
water pipes or when openings around pipes are not
protected by non-combustible materials.
Boiler must not be connected to a chiller. If the boiler
supplies hot water to heating coils in air handling units,
flow control valves or other devices must be installed to
prevent gravity circulation of boiler water in the coils
during the cooling cycle.
NOTICE: USE PIPE DOPE SPARINGLY AND SPREAD
AROUND MALE PIPE THREADS ONLY.
Expansion Tank: (Provided) To install, see Figure 14.
Piping systems with unusually large water volume may
require the connection of a larger capacity expansion
tank outside of the boiler’s enclosure.
Relief ValveDischarge Piping: Install behind supply
water pipe. Use same size or larger piping (iron or cop-
per) than valve outlet. Must terminate 6" from floor (or
local codes) with a plain (no threads) end. DO NOT
hard-pipe to drain piping. Make sure discharge is
always visible.
Cold Water Fill: Pressure reducing (fill) valve and shutoff
valve should be installed.
Supply and Return: For tapping sizes, see dimensions
on Page 3. Recommend shutoff valve in supply (and
shutoff and drain valves in return on non-zoned sys-
tem).
Radiant Floor and Standing Iron Radiant Systems:A
boiler by-pass loop (or equivalent) will be required to
avoid flue gas condensation on cast iron sections for
low temperature application. (i.e. radiant floor systems.)
Zone Piping: See Page 20 for zoning with zone valves
and domestic hot water installation.
STEP 4: FILL AND PURGE HEATING SYSTEM
•Make sure flow direction arrows on components are
facing in direction of flow.
•Place bucket under pressure relief valve discharge.
BASEBOARD AND RADIANT FLOOR SYSTEMS
•Close all shutoff valves, drain valves and air vents.
•Open supply shutoff valve and return drain valve on
first zone (or return drain valve on non-zoned system).
If zoned with zone valves, manually open zone valve.
•Attach a hose from return drain valve to a drain. Open
fill line shutoff valve. Manually operate fill valve regula-
tor. When water runs out of hose in a steady stream
(with no air bubbles), close return drain valve.
•Repeat procedure for additional zones (one at a time).
•On completion, open all return shutoff valves.
STANDING IRON RADIATION AND SYSTEMS WITH
MANUAL VENTS ATHIGH POINTS
•Close all shutoff valves, drain valves and air vents.
•Open supply and return shutoff valves. If zoned with
zone valves, manually open all zone valves.
•Open fill line shutoff valve. Manually operate fill valve
regulator. Open pressure relief valve manual operator
to fill boiler. When water runs out of discharge pipe in
steady stream (with no air bubbles), close operator.
•Starting with nearest manual air vent, open vent until
water flows out; close vent. Repeat procedure, working
your way toward farthest air vent.
WHEN FINISHED
•Place fill valve regulator and all zone valve operators
in automatic position.
•Check that temperature/pressure gage reads minimum
of 12 psi (fill pressure); exact pressure will vary with
altitude. If piping system rises more than 16 feet verti-
cally above boiler, higher fill pressures are required.
•Check for and repair any water leaks.

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STEP 5: SELECT GAS PIPE SIZE
Install Manual
Main Shutoff
Above Floor
When Required
By Local Code
Valve 5 ft.
Gas
Supply
Gas Valve
Union
Full Size
Sediment
Trap
Figure 15: Gas Piping Component Locations
•Measure length of piping from gas meter to farthest
appliance on gas line. MEASURE BOTH VERTICAL
AND HORIZONTAL RUNS. This is the only measure-
ment required regardless of which portion of the gas
piping is being sized. No allowance required for fit-
tings.
•Using sizing table below, enter table at top with num-
ber of running feet.
•Read down and match boiler’s input to capacity
(cu.ft./hr). If the input falls between two numbers,
always use higher capacity.
•Read across to left side of table for correct pipe size.
Example: Prodigy Model KC-90, with 90,000 input, will
be installed. Measured length of piping is 30 feet. From
chart, a “matched” capacity would be 152; so, pipe size
would be 3/4".
STEP 6: INSTALL AND TEST GAS PIPING SYSTEM
Where it’s applicable, local codes supercede these
instructions. Always follow good piping practices.
Inspect piping thoroughly for cleanliness before make-
up. Pipe dope must be compatible with gas (NG or LP).
NEVER use teflon tape or hard-setting compounds.
NOTICE: USE PIPE DOPE SPARINGL
YAND SPREAD
AROUND MALE PIPE THREADS ONLY.
Gas Piping Components: Install piping from gas meter
to boiler with a manual main shutoff valve (recommend
afull port, ball-type valve approved for use with gas), a
ground joint union and full size sediment trap.
Piping Supports: Horizontal piping must be supported
by hangers, not by the boiler or accessories. Space
hangers 8 feet apart (or local codes).
GAS SUPPLY PRESSURE
Minimum and maximum gas supply pressure to the gas
valveis provided on the boiler rating plate. Check local
utility for pressure being supplied. If pressure is below
minimum, contact the gas utility. If pressure is above
maximum, install a 100% lock-up gas pressure regula-
tor in gas supply line and adjust to maximum boiler gas
pressure.
LEAK TEST GAS PIPING
For test pressures of 13" w.c. or less, isolate the boiler
from gas piping byclosing the manual main shutoff val-
ve. For test pressures greater than 13" w.c., disconnect
boiler gas valve from the gas piping. Pressurize the gas
piping and bubble test all piping and boiler connections
for leaks using soap solution.
DANGER: DO NOT USE FLAME TO CHECK FOR
GAS LEAKS. FIRE OR EXPLOSION CAN RESULT.
10 20 30 40 50 60 70 80 90 100 125 150 175 200
3⁄4” 278 190 152 130 115 105 96 90 84 79 72 64 59 55
1” 520 350 285 245 215 195 180 170 160 150 130 120 110 100
11⁄4” 1050 730 590 500 440 400 370 350 320 305 275 250 225 210
11⁄2” 1600 1100 890 760 670 610 560 530 490 460 410 380 350 320
2” 3050 2100 1650 1450 1270 1150 1050 990 930 870 780 710 650 610
Schedule
40
Pipe
Size
Maximum Capacity of Pipe (cu.ft./hr.) for Gas Pressures of 0.5 psig or Less
and Pressure Drop of 0.3” W.C. (Based on 0.60 Specific Gravity Gas)