Lochinvar POWER-FIN PF0501 User manual

DESIGNER’S GUIDE POWER-FIN®WATER HEATER
500,000 – 2,000,000 Btu/hr

Dear Specifier/Project Manager,
At Lochinvar, we have long recognized the importance of innovation to any
product or service. Those who enter into business must also accept the challenge
of meeting constantly changing needs.
The designer’s guide you are now holding has been designed to make it more
convenient for you to select the perfect Lochinvar water heater for your projects
and provide correct specifications for your teams.
All information has been organized and presented in a succinct, easy-to-use
manner, so you can use and share information confidently and with minimal
effort.
However, it is important to remember that this guide is not intended to replace our
installation manual. Installers should still refer to our installation manual for
specific installation instructions.
We hope our manual will make your work easier and more productive.
As always, we greatly appreciate your input on additional improvements for the
future.
Thanks once again for specifying the Lochinvar family of quality standard
and custom-built water heaters and boilers.
Sincerely,
Lochinvar Corporation
Lochinvar Corporation • 615-889-8900 • Fax: [phone]

Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
Table of Contents
Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Combustion & Ventilation Air . . . . . . . . . . . . . . . . .5
Contaminants . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Determining Total "Free" Area . . . . . . . . . . . . . . . . .5
Electrical Requirements . . . . . . . . . . . . . . . . . . . . .20
Gas Bleeds & Vents . . . . . . . . . . . . . . . . . . . . . . .18
Gas Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
General Venting . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Location of Unit . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Low Water Temperature Delivery . . . . . . . . . . . . . .18
Pump Operation . . . . . . . . . . . . . . . . . . . . . . . . .19
Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Venting Overview . . . . . . . . . . . . . . . . . . . . . . . . .8
Venting Options . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Water Connections . . . . . . . . . . . . . . . . . . . . . . .18
Water Treatment . . . . . . . . . . . . . . . . . . . . . . . . .19
Water Velocity Control . . . . . . . . . . . . . . . . . . . . .18
Figures & Tables Index
FIG. 1 Clearances From Combustibles . . . . . . . . .3
FIG. 2 Water Heater Equipment
And Control Orientation . . . . . . . . . . . . . .4
FIG. 3-6 Combustion And Ventilation Air . . . . . . . . .5
FIG. 7 Conventional Negative Draft Venting . . . . .9
FIG. 8 Vertical Negative Draft Venting . . . . . . . . .9
FIG. 9 Vertical Positive Pressure Venting . . . . . . . .9
FIG. 10 Multiple Unit Barometric Damper Installation10
FIG. 11 Sidewall Venting . . . . . . . . . . . . . . . . . .10
FIG. 12 Location Of Sidewall Vent Termination . . .11
FIG. 13 DirectAire Vertical w/ Sidewall Air Inlet . .14
FIG. 14 DirectAire Vertical w/ Rooftop Air Inlet . .15
FIG. 15 DirectAire Horizontal w/ Rooftop Air Inlet 15
FIG. 16 DirectAire Horizontal w/ Sidewall Air Inlet
In A Different Pressure Zone . . . . . . . . . .15
FIG. 17 Direct Vent Vertical . . . . . . . . . . . . . . . . .16
FIG. 18 Direct Vent Horizontal . . . . . . . . . . . . . .16
TABLE A Clearances From Combustibles . . . . . . . . .3
TABLE B Power-Fin Venting Configurations . . . . . . .8
TABLE C Sidewall Vent Kits . . . . . . . . . . . . . . . . .10
TABLE D Sidewall Air Inlet Kits . . . . . . . . . . . . . . .12
TABLE E Flue & Combustion Air Pipe Sizes . . . . . .14
TABLE F Horizontal Direct Vent Kits . . . . . . . . . . .16
TABLE G Gas Supply Pipe Sizing . . . . . . . . . . . . .17
TABLE H Inlet Gas Pressure Requirements . . . . . . .18
TABLE I Required Temperature Rise . . . . . . . . . . .18
TABLE J Required Pump Performance . . . . . . . . .19
TABLE K Common Water Manifold Sizes . . . . . . .20
TABLE L Amp Draw . . . . . . . . . . . . . . . . . . . . . .20
Water Heater Piping Diagrams
Single Heater - Single Tank . . . . . . . . . . . . . . . . . .A1
Single Heater - Two Tanks . . . . . . . . . . . . . . . . . .A2
Two Temperature Installation
/ Single Heater - Single Tank . . . . . . . . . . . . . . .A3
Two Heaters - Single Tank . . . . . . . . . . . . . . . . . .A4
Two Heaters - Two Tanks . . . . . . . . . . . . . . . . . . .A5

CODES
The equipment shall be installed in
accordance with those installation regulations
in force in the local area where the installation
is to be made. These shall be carefully
followed in all cases. Authorities having
jurisdiction should be consulted before
installations are made.
In the absence of such requirements, the
installation shall conform to the latest edition of
the National Fuel Gas Code, ANSI Z223.1.
Where required by the authority having
jurisdiction, the installation must conform to
American Society of Mechanical Engineers
Safety Code for Controls and Safety Devices
for Automatically Fired Water heaters, ASME
CSD-1. Where required by the authority
having jurisdiction, the installation must
comply with the Canadian Association Code,
CAN/CGA-B149.1 and/or B149.2 and/or
local codes.
LOCATION OF UNIT
These units are suitable for indoor
installation only. Venting options and
configurations are illustrated in the
venting section.
Indoor units must be installed so that
the ignition system components are
protected from water (dripping, spraying,
rain, etc.) during appliance operation and
service (circulator replacement, control
replacement, etc.).
2Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
Lochinvar
•Water Velocity – Flow Rate
(See page 18 for Required
Temperature Rise chart.)
•Factory Supplied Pump-Capacity
(See page 19 for Pump Operation.)
•Manifold Pipe Size
when using more than one
heater (See page 20 for Common
Manifold Size for Multiple Water
Heater Installation table.)
•Storage Tank Circulating Tappings
(See page 20 for Manifold Pipe
Size above.)
•Placement of Cold Water
Inlet and Building Return
(See Appendix A for Water Heater
Piping Diagrams.)
• Water Hardness
(See page 19 for Water Treatment
Information.)
In designing a hot
water heating system,
pay special attention to:
1.

Locate the unit so that if the water
connections should leak, water damage
will not occur. When such locations cannot
be avoided, it is recommended that a
suitable drain pan, adequately drained, be
installed under the unit. The pan must not
restrict combustion air flow.
Allow sufficient space in the back of
water heater for servicing pipe
connections, pump, and other auxiliary
equipment, as well as the unit.
The unit must be placed on a
level floor; combustible floor locations
may be used.
2.
3.
4.
Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900 3
(TABLE A) - CLEARANCES FROM COMBUSTIBLES
Location Clearances
Right Side 0"
Rear 6" (24" for service)
Left Side 0"
Front ALCOVE* (24" for service)
Top 6" (24" for service)
Flue 2"
Hot Water Pipes 1"
* Alcove is a closet without a door.
Under no circumstances is the
manufacturer to be held responsible
for water damage in connection with
this unit or any of its components.
(FIG. 1) CLEARANCES FROM COMBUSTIBLE CONSTRUCTION

4Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
Lochinvar
(FIG. 2) WATER HEATER EQUIPMENT AND CONTROL ORIENTATION
PF1500-2000
PF0501-1300
GAS
CONNECTION
ELECTRICAL
CONNECTION INLET
AIR
HOT WATER
OUTLET
HEAT EXCHANGER
DRAINS FLUE
DIAGNOSTIC
PANEL
COLD WATER
INLET
GAS
CONNECTION
ELECTRICAL
CONNECTION INLET
AIR
HOT WATER
OUTLET
HEAT EXCHANGER
DRAINS FLUE
COLD WATER
INLET
DIAGNOSTIC
PANEL

Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900 5
COMBUSTION &
VENTILATION AIR
Provisions for combustion and ventilation air
must be in accordance with Section 5.3,
Air For Combustion And Ventilation, of the
latest edition of the National Fuel Gas Code
ANSI Z223.1, or applicable provisions of
the local building codes.
If air is taken directly from outside the
building with no duct (FIG. 3):
A. Combustion air opening, one square
inch per 4000 Btu/hr input. This opening
must be located within 12” of the
bottom of the enclosure.
B. Ventilation air opening, one square
inch per 4000 Btu/hr input. This opening
must be located within 12” of the top of
the enclosure.
If air is taken from another interior space
(FIG. 4), each opening specified above
should have a net free area of one square
inch for each 1000 Btu/hr input.
If combustion and ventilation air is taken
from the outdoors using a duct to deliver
the air to the mechanical room (FIG. 5),
each opening should have a net free
area of one square inch per 2000
Btu/hr input.
If a single combustion air opening is
provided to bring combustion air in
directly from the outdoors (FIG. 6), the
opening should have a net free area of
one square inch per 3000 Btu/hr input.
This opening must be located under 12”
of the top of the enclosure.
(FIG. 3) COMBUSTION AIR DIRECT FROM OUTSIDE
(FIG. 6) COMBUSTION AIR DIRECT FROM OUTSIDE
SINGLE OPENING
(FIG. 5) COMBUSTION AIR THROUGH DUCTWORK
(FIG. 4) COMBUSTION AIR FROM AN INTERIOR SPACE
1.
2.
3.
4.
CAUTION: Under no circumstances
should the equipment room be under a
negative pressure, when atmospheric
combustion equipment is installed in the
room.
EXAMPLE OF
SIZING FOR
COMBUSTION
& VENTILATION
AIR OPENINGS
(UNIT WITH
1,000,000
Btu/hr INPUT):
When combustion and
ventilation air is taken
from directly outside the
building (FIG. 3), divide
the total Btu/hr by
4,000. This yields 250
sq.in. of “Free Area”
without restriction.
1,000,000 ÷ 4,000 =
250 sq.in.
Since the air opening is
50% closed due to
screens and louvers, the
total opening must be
multiplied by 2.
250 sq.in. x 2 =
500 sq.in.
This project requires one
Ventilation Air Opening
with a net “Area” of
500 square inches with
louver dimensions of
20” x 25” and one
Combustion Air Opening
with a net “Area” of
500 square inches with
louver dimensions of
20” x 25”.

6Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
CONTAMINANTS
Combustion air drawn from an interior
or exterior space must be free of any
chemical fumes which could be corrosive to
the water heater. Burning chemical fumes
results in the formation of corrosive acids
which attack the water heater, cause
improper combustion and premature failure
of the water heater and vent.
These fumes are often present in areas
where refrigerants, salts, and solvents are
used. Therefore, be mindful of swimming
pool equipment, water softening, and
cooling system placement.
VENTING
General
Vent installations for connection to gas vents
or chimneys must be in accordance with
Part 7, "Venting of Equipment," of the latest
edition of the National Fuel Gas Code,
ANSI Z223.1, or applicable provisions
of the local building codes.
The connection from the appliance vent to
the stack must be as direct as possible and
sized correctly. The horizontal breeching of
a vent must have at least 1/4" rise per
linear foot. The horizontal portions should
also be supported for the design and weight
of the material employed to maintain
clearances, prevent physical damage and
separation of joints.
The connection from the appliance vent to
the stack or vent termination outside the
building must be made with appropriate
vent category connectors and sized
according to vent sizing tables (FAN column)
in the latest edition of the National Fuel Gas
Code.
The vent and accessories, such as firestop
spacers, thimbles, caps, etc., must be
installed in accordance with the vent
manufacturer's listing. The vent connector
and firestop must provide correct spacing to
combustible surfaces and seal to the vent
connector on the upper and lower sides of
each floor or ceiling through which the vent
connector passes.
Any improper operation of the common
venting system in an existing building should
be corrected when new equipment is
installed, so the installation conforms to the
latest edition of the National Fuel Gas Code,
ANSI Z223.1.
When resizing any portion of the common
venting system, it should be resized to
approach the minimum size as determined
using the appropriate tables in the National
Fuel Gas Code.
The weight of the venting system must not
rest on the unit. The venting system must be
adequately supported in compliance with
local codes and other applicable codes.
Vent Terminations
The vent terminal should be vertical and
exhaust outside the building at least 2 feet
(0.6 m) above the highest point of the roof
when within a 10 foot (3.05 m) radius.
Lochinvar
IMPORTANT!
This appliance is a high
efficiency unit. It
operates at an efficiency
level which could yield a
condensing condition.
Care should be taken in
providing the proper
venting and employing
the best principles of
application and sizing.

Additionally, vertical terminations must be a
minimum of 3 feet (0.9 m) above the roof
line, and when less than 10 feet (3.05 m)
from a parapet wall must be a minimum of
2 feet (0.61 m) higher than the parapet wall.
Vent caps should have a minimum clearance
of 4 feet (1.2 m) horizontally from, and in
no case above or below [unless a 4 feet
(1.2 m) horizontal distance is maintained],
electric meters, gas meters, regulators and
relief equipment.
Maintain a distance of at least 3 feet (0.9
m) above any forced air inlet within 10 feet
(3.05 m) and a distance of at least 4 feet
(1.2 m) below, 4 feet (1.2 m) horizontally
from, or 1 foot (30 cm) above any door,
window or gravity air inlet.
Do not terminate the vent in a window well,
stairwell, alcove, courtyard or other recessed
area. The vent can not terminate below
grade. The bottom of the vent terminal shall
be located at least 12 inches (30 cm) above
grade and clear of snow, ice, leaves or
other debris.
The distance of the vent terminal from
adjacent public walkways, adjacent
buildings, windows, and building openings
must be consistent with the National Fuel
Gas Code Z223.1 or in Canada, the latest
edition of CGA Standard B149 Installation
Code for Gas Burning Appliances and
Equipment.
Masonry Chimneys
A masonry chimney must be properly sized
and lined for the installation of a high
efficiency gas fired appliance. Venting of a
high efficiency appliance into a cold,
oversized and unlined masonry chimney can
result in operational and safety problems. A
standard masonry chimney must not be used
to vent the products of combustion from this
high efficiency gas fired appliance.
A masonry chimney must be carefully
inspected to determine its suitability for
the venting of flue products.
An unlined chimney must be relined with
an approved chimney liner system when a
new appliance is being attached to it. Metallic
liner systems (Type "B" double-wall or flexible
or rigid metallic liners) are recommended for
non-condensing, negative draft systems.
Sealed, metallic, corrosion resistant liner
systems (single-wall, double-wall, flexible or
rigid metallic liners) rated for use with a high
efficiency, Category IV appliances must be
used with positive pressure systems.
Corrosion resistant chimney liner systems
are typically made from a high grade of
corrosion resistant stainless steel such as AL29-
4C. The corrosion resistant liner must be
properly sized and fully sealed throughout the
entire length contained within the masonry
chimney. Both the top and bottom of the
masonry chimney must be capped and sealed
to provide a dead air space around the liner.
Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900 7
IMPORTANT!
The vent cap should
have a minimum
clearance of 4 feet
horizontally from
electric meters, gas
meters, regulators, air
inlets and air relief
equipment. Additionally,
the vent cap should
never be located above
or below these items,
unless a 4 foot
horizontal distance
is maintained.
NOTE:
An unlined masonry
chimney must not be
used to vent flue
products from this
high efficiency
appliance.

8Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
VENTING OVERVIEW
CATEGORY I DOUBLE-WALL B-VENT
(ON/OFF - ONLY)
Conventional Vertical Negative Draft
Venting with a vertical rooftop termination
and combustion air supplied from the
equipment room.
Vertical DirectAire Venting uses a vertical
negative draft flue with a rooftop termination
for flue products and a combustion air pipe
from the sidewall or rooftop.
CATEGORY IV VENT MATERIAL
(ALL MODELS)
Vertical Negative Draft Venting with a vertical
rooftop termination and combustion air
supplied from the equipment room. (Note:
B-Vent may be used with ON/OFF models)
Vertical Positive Pressure Venting with a
vertical rooftop termination and combustion
air supplied from the equipment room.
Sidewall Venting uses the unit's internal fan to
exhaust the flue products out to a sidewall
vent termination with combustion air supplied
from the equipment room.
Vertical DirectAire Venting (Sidewall Inlet) with
a vertical rooftop termination for flue products
and a combustion air pipe from the sidewall.
(Note: B-Vent may be used with ON/OFF
models)
Horizontal DirectAire Venting uses the unit's
internal fan to exhaust the flue products out a
sidewall vent termination with a combustion
air pipe from the rooftop or from a sidewall
other than where the flue terminates.
Horizontal or Vertical Direct Venting uses the
unit's internal fan to exhaust the flue products
out to a sidewall or rooftop vent termination
with a separate sealed combustion air pipe to
the outdoors. This system terminates both the
flue and combustion air inlet on the same
surface and in the same pressure zone.
Lochinvar
CAUTION!
Vent connectors
serving appliances
vented by natural
draft must not be
connected into any
portion of mechanical
draft systems
operating under a
positive pressure.
(TABLE B) POWER-FIN VENTING CONFIGURATIONS
VERTICAL VERTICAL
FIRING VERTICAL VERTICAL DirectAire DirectAire
BTU/HR CODE FIRING NEGATIVE POSITIVE w/ ROOFTOP w/ SIDEWALL HORIZONTAL VERTICAL HORIZONTAL
INPUT PREFIX CONTROLS DRAFT PRESSURE AIR INLET AIR INLET DirectAire SIDEWALL DIRECT VENT DIRECT VENT
500,000 F ON/OFF CAT. I --- CAT. I CAT. I CAT. IV CAT. IV CAT. IV CAT. IV
500,000 M MODULATING CAT. II --- --- CAT. II CAT. IV CAT. IV CAT. IV CAT. IV
750,000 F ON/OFF CAT. I --- CAT. I CAT. I CAT. IV CAT. IV CAT. IV CAT. IV
750,000 M MODULATING CAT. II --- --- CAT. II CAT. IV CAT. IV CAT. IV CAT. IV
1,000,000 F ON/OFF CAT. I --- CAT. I CAT. I CAT. IV CAT. IV CAT. IV CAT. IV
1,000,000 M MODULATING CAT. II --- --- CAT. II CAT. IV CAT. IV CAT. IV CAT. IV
1,300,000 F ON/OFF CAT. I --- CAT. I CAT. I CAT. IV CAT. IV CAT. IV CAT. IV
1,300,000 M MODULATING CAT. II --- --- CAT. II CAT. IV CAT. IV CAT. IV CAT. IV
1,500,000 M MODULATING --- CAT. IV --- CAT. IV CAT. IV CAT. IV CAT. IV CAT. IV
1,700,000 M MODULATING --- CAT. IV --- CAT. IV CAT. IV CAT. IV CAT. IV CAT. IV
2,000,000 M MODULATING --- CAT. IV --- CAT. IV CAT. IV CAT. IV CAT. IV CAT. IV
NOTE: Category II venting configurations must be installed with corrosion resistant vent material.

VENTING OPTIONS
Conventional Vertical Negative Draft
Venting with Combustion Air
Supplied from the Equipment Room
(PF0501-1300 Models - Only)
Units with ON/OFF burner controls may be
vented with Category I, Type "B" vent
material. Only ON/OFF units can be vented
with standard double-wall vent material. The
flue must terminate at the rooftop. Combustion
air is supplied from the equipment room. The
installation of the vent must conform to the
latest edition of the National Fuel Gas Code,
ANSI Z223.1, in Canada, the latest edition
of CGA Standard B149 Installation Code for
Gas Burning Appliances and Equipment. The
vent system must maintain a negative draft
within the specified range of 0.2 to 0.8
inches of water column.
Vertical Negative Draft Venting
with Combustion Air Supplied
from the Equipment Room
(PF0501 - 1300 Models - Only)
Units with Modulating burner controls that can
be vented with a negative draft vent system are
classified as Category II appliances and must
be vented with Category IV corrosion resistant
vent material. The vent connection is made
directly to the back of the unit using an AL29-
4C corrosion resistant vent pipe. The flue must
terminate at the rooftop. Combustion air is
supplied from the equipment room.
Vertical Positive Pressure Venting
with Combustion Air Supplied from
the Equipment Room
(PF1500 - 2000 Models - Only)
Units with Modulating burner controls that use
their internal combustion fan to force the flue
products out the vent system are classified as
Category IV, positive pressure appliances and
must be vented with Category IV corrosion
resistant vent material. The vent connection is
made directly to the back of the unit using an
AL29-4C corrosion resistant vent pipe. The flue
must terminate at the rooftop. Combustion air is
supplied from the equipment room.
The modulation of the burner may result in
flue gas temperatures below dew point
which may form condensate in the flue. The
unit's internal fan generates a positive draft
pressure to exhaust the flue products.
Therefore, materials used for a Category IV
positive pressure vent must be sealed and
corrosion resistant.
Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900 9
CAUTION!
In cold climates,
flue products will
produce a noticeable
plume. Carefully select
the location of vent caps
for vertical and
horizontal applications.
(FIG. 7) CONVENTIONAL NEGATIVE DRAFT VENTING
(FIG. 9) VERTICAL POSITIVE PRESSURE VENTING
(FIG. 8) VERTICAL NEGATIVE DRAFT VENTING

10 Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
Common Venting Systems
Category IV positive pressure vent systems
CANNOT be combined with negative draft
Category I or II vent systems under any
circumstances. The vent from Category I
appliances CANNOT be combined with the
flue from Category II appliances unless the
entire vent system for all units uses corrosion
resistant, Category IV vent materials. A
barometric damper must be installed on
each unit when common venting multiple
negative draft appliances.
Only Category I and Category II negative
draft appliances may be common vented.
Positive pressure, Category IV vents
CANNOT be combined without the use of
an engineered exhaust evacuation system
such as a Lochinvar Intelli-Vent system.
Sidewall Venting
A sidewall venting system (FIG. 11) uses the
unit's internal combustion fan to force the
flue products out a sidewall vent cap. The
unit's internal fan generates a positive draft
pressure to exhaust the flue products.
Combustion air is drawn from the equipment
room.
The connection from the appliance flue outlet
to the sidewall vent cap must be made with
Category IV type vent materials for both
ON/OFF and Modulating models. The
sidewall vent cap must be purchased from
the appliance manufacturer as per CSA
International requirements.
The Category IV flue from this appliance
CANNOT be combined with the vent from
any other appliance. The flue must be a
dedicated stack and must have all vent joints
and seams sealed gastight.
Locally purchased or fabricated sidewall vent
caps must not be used. The part numbers for
the required sidewall vent cap kit are listed in
TABLE C. Each kit includes the vent cap for
installation on an exterior sidewall for
operation of a single appliance only.
Lochinvar
(FIG. 11) SIDEWALL VENTING
(TABLE C) – SIDEWALL VENT KITS
MODEL FLUE VENT
NUMBER SIZE CAP
PF0501 7" SVK3027
PF0751 9" SVK3049
PF1001 10" SVK3029
PF1300 12" SVK3050
PF1500 8" SVK3028
PF1700 8" SVK3028
PF2000 10" SVK3029
(FIG. 10) MULTIPLE UNIT BAROMETRIC
DAMPER INSTALLATION
NOTE:
Some discoloration to
building exterior or
unit surfaces can be
expected. Adjacent brick
or masonry surfaces
should be protected
with a rust resistant
sheet metal plate.

Maximum Length of Sidewall Vent Pipe
The maximum installed length of the flue from
the appliance to the point of termination,
outside of the building, must
not exceed a maximum of 50 equivalent feet
(15.2m) in length. Subtract 5 feet (1.5m)
of equivalent length for each 90° elbow
and 2-1/2 feet (0.7m) of equivalent length for
each 45° elbow installed in the vent.
Location of a Sidewall Vent Termination
The vent cap shall terminate at least 3 feet
(0.91m) above any forced air inlet within 10
feet (3.05m). The vent shall terminate at least
4 feet (1.22m) below, 4 feet (1.22m)
horizontally from, or 1 foot (0.30m) above
and 2 feet (0.60m) horizontally from any
door, window, or gravity air inlet to the
building. The sidewall vent termination must
be at least 8 feet (2.4m) horizontally from any
combustion air intake located above the
sidewall termination cap.
Do not terminate the vent in a window well,
stairwell, alcove, courtyard, or other recessed
area. The vent cannot terminate below grade.
The vent shall not terminate directly above a
public walkway due to the normal formation
of water vapor in the combustion process.
Horizontal terminations must not be located
over areas of pedestrian or vehicular traffic.
The vent system shall terminate at least 1 foot
(0.30m) above grade, above normal snow
levels and at least 7 feet (2.13m) above grade
when located adjacent to public walkways.
The vent terminal shall not be installed closer
than 3 feet (0.91m) from an inside corner of
an L-shaped structure. The vent cap should
have a minimum clearance of 4 feet (1.22m)
horizontally from and in no case above or
below, unless a 4 foot (1.22m) horizontal
distance is maintained from electric meters,
gas meters, regulators and relief equipment.
Flue gas condensate can freeze on exterior
walls or on the vent cap. Frozen condensate
on the vent cap can result in a blocked flue
condition. Some discoloration to exterior
building surfaces can be expected. Adjacent
brick or masonry surfaces should be protected
with a rust resistant sheet metal plate.
DIRECTAIRE AND DIRECT VENT SYSTEMS
Direct Vent and DirectAire Vent Systems are
installed with specific flue pipe material
requirements based on the type of firing
controls used on the unit. Direct Vent and
DirectAire systems both use a separate
combustion air pipe to the outdoors.
The Direct Vent System terminates both the flue
and combustion air inlet in the same pressure
zone. The DirectAire Vent System may
terminate the flue and combustion air inlet in
different pressure zones. The flue outlet and
combustion air inlet may terminate with either
a sidewall or a rooftop termination based on
the specific venting option selected.
DirectAire and Direct Vent Systems require the
installation of an additional Air Inlet pipe to
supply combustion air from outdoors directly
to the appliance.
Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900 11
(FIG. 12) LOCATION OF A SIDEWALL VENT TERMINATION
WARNING
No substitutions of flue
pipe or vent cap
material are allowed
when direct venting.
Such substitutions would
jeopardize the safety
and health of building
inhabitants.

Maximum Length Air Inlet Pipe
The maximum installed length of the sidewall
or vertical rooftop combustion air inlet pipe
must not exceed 50 equivalent feet (15.2m)
in length. Subtract 5 feet (1.52m) of equivalent
length for each 90° elbow and 2-1/2 feet
(0.7m) of equivalent length for each 45°
elbow installed in the air inlet pipe system.
Air Inlet Pipe Materials
The following air inlet pipe materials are
acceptable:
PVC, CPVC, ABS, Dryer Vent or Sealed
Flexible Duct (not recommended for rooftop air
inlet), galvanized steel vent pipe with joints
and seams sealed and type "B" double-wall
vent with joints and seams sealed.
The air inlet pipe must be sealed. Proper
sealing of the air inlet pipe ensures that
combustion air will be free of contaminants
and supplied in proper volume. When a
sidewall or vertical rooftop combustion air
supply system is disconnected for any reason,
the air inlet pipe must be resealed to ensure
that combustion air will be free of
contaminants and supplied in proper volume.
Sidewall Combustion Air Inlet
The air inlet cap for the sidewall air inlet
option must be purchased from the appliance
manufacturer as per CSA International
requirements. The part numbers for the
required sidewall air inlet cap kit are listed in
TABLE D. Each kit includes the combustion air
inlet cap for installation on an exterior sidewall
for operation of a single appliance only.
Location of a Sidewall Air Inlet Cap
Incorrect installation and/or location of the
air inlet cap may allow the discharge of flue
products to be drawn into the combustion
process of the unit. This may result in
incomplete combustion and potentially
hazardous levels of carbon monoxide in the
flue products. This will cause operational
problems with the unit and may result in
possible spillage of flue products that can
cause personal injury, death or property
damage.
The termination point of the sidewall air inlet
must be located a minimum of 12 inches
(0.30 m) above ground level and above
normal levels of snow accumulation. The
point of termination for the sidewall air inlet
cap must be located a minimum of 3 feet
(0.91m) horizontally and 12 inches (0.30
m) below the point of any flue gas
termination if the air inlet is located within a
10 foot (3.05 m) radius of the flue outlet.
The sidewall air inlet cap must not be
installed above a sidewall flue outlet if it is
located within a 10 foot (3.05m) radius of
the flue outlet.
Lochinvar
12 Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
(TABLE D) – SIDEWALL AIR INLET KITS
MODEL AIR AIR INLET
NUMBER INLET CAP
PF0501 5" SAK3003
PF0751 5" SAK3003
PF1001 6" SAK3000
PF1300 6" SAK3000
PF1500 6" SAK3000
PF1700 8" SAK3001
PF2000 8" SAK3001

The sidewall air inlet cap must not be
installed closer than 10 feet (3.05m) from
an inside corner of an L shaped structure.
The sidewall air inlet cap assembly must
adequately protect the combustion air inlet
from wind and weather.
Rooftop Combustion Air Inlet
The air inlet cap for the rooftop combustion
air inlet is not supplied by the manufacturer
and must be purchased locally. The air inlet
cap consists of two 90° elbows installed at
the point of termination for the air inlet pipe.
Location of Rooftop Air Inlet Cap
Incorrect installation and/or location of the
air inlet cap may allow the discharge of flue
products to be drawn into the combustion
process of the unit. This may result in
incomplete combustion and potentially
hazardous levels of carbon monoxide in the
flue products. This will cause operational
problems with the unit and may result in
possible spillage of flue products that can
cause personal injury, death or property
damage.
The termination point of the rooftop air inlet
must be located a minimum of 12" (0.30 m)
above the roof or above normal levels of
snow accumulation. The point of
termination for the air inlet cap must be
located a minimum of 3 feet (0.91m) below
any point of flue gas termination if the air
inlet is located within a 10 foot (3.05m)
radius of the flue outlet.
The rooftop air inlet cap must not be
installed closer than 10 feet (3.05 m) from
an inside corner of an L shaped structure.
The rooftop air inlet cap assembly must
adequately protect the combustion air inlet
from wind and weather.
DirectAire Systems
A DirectAire vent system uses a flue to the
sidewall or rooftop with a separate combustion
air inlet pipe to the outdoors. The DirectAire vent
system may terminate the flue and the
combustion air inlet pipe in different pressure
zones in any one of three configurations as
shown in figures 13, 15 and 16.
• The flue on the rooftop and combustion
air inlet on the sidewall. (FIG. 13)
• The flue on the sidewall and combustion
air inlet on the rooftop. (FIG. 15)
• The flue on the sidewall and the combustion
air inlet on a sidewall other than the
sidewall where the flue is located. (FIG. 16)
Units with ON/OFF burner controls utilizing
Category I, negative draft venting may be
configured as a DirectAire system and may
have both the flue and air inlet terminated
on the rooftop in the same pressure zone.
(See FIG. 14)
DirectAire vent systems require the
installation of specific venting materials.
Rooftop flue gas termination caps and
combustion air inlets must be purchased
locally. Sidewall flue gas termination caps
and combustion air inlets must be purchased
from the appliance manufacturer as per
CSA International requirements.
Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900 13

14 Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
Combined Combustion Air Inlet Points
for DirectAire Systems Only
The air inlet pipes from multiple appliances
can be combined into a single common
connection if the common air inlet pipe has
a cross sectional area equal to, or greater
than, the total area of all air inlet pipes
connected to the common air inlet pipe.
The air inlet point for multiple units must be
provided with an exterior opening which
has a free area equal to, or greater than,
the total area of all air inlet pipes connected
to the common air inlet. This exterior
opening for combustion air must connect
directly to the outdoors. The total length of
the combined air inlet pipe must not exceed
a maximum of 50 (15.2m) equivalent feet.
You must deduct the restriction in area
provided by any screens, grills or louvers
installed in the common air inlet point.
Screens, grills, or louvers installed in the
common air inlet can reduce the free area
of the opening from 25% to 75% based
on the materials used.
DirectAire Vertical
DirectAire Vertical vent systems are installed
with the flue terminating at the rooftop and
a separate combustion air inlet pipe at the
sidewall to draw air from the outdoors. The
flue outlet and combustion air inlet terminate
in different pressure zones.
The maximum installed length of the
combustion air inlet pipe and positive
pressure flue gas vent pipe must not
exceed 50 equivalent feet (15.2m) in
length per pipe.
EXCEPTION: For negative draft models
(PF0501-1300) the maximum installed
length of the flue gas vent pipe from the
appliance to the termination cap is limited
only by the requirement to maintain a
negative draft within the specified range
of 0.2 to 0.8 inches of water column.
The flue and air inlet sizes for DirectAire
Vertical systems with Sidewall Air Inlet are
listed in TABLE E. This venting option uses a
vent termination constructed from materials
purchased locally by the installer and a
sidewall air inlet purchased from the
manufacturer. The part numbers for the
required sidewall air inlet cap kit are listed
in TABLE D.
Lochinvar
(TABLE E) – FLUE & COMBUSTION
AIR PIPE SIZES
MODEL AIR
NUMBER FLUE INLET
PF0501 7" 5"
PF0751 9" 5"
PF1001 10" 6"
PF1300 12" 6"
PF1500 8" 6"
PF1700 8" 8"
PF2000 10" 8"
(FIG. 13) DIRECTAIRE VERTICAL W/SIDEWALL AIR INLET
EXAMPLE OF
COMBINED AIR
INLET SIZING:
Two 5" (12.7cm) air inlet
pipes, 19.63 in² (126.6
cm²) in free area each,
have a total combined
free area of 39.26 in²
(253.3 cm²). These two
pipes require an 8" (20.3
cm) common air inlet
pipe, with 50.26 in²
(324.3 cm²) of free area.

Rooftop Combustion Air Inlet
(PF0501-1300 ON/OFF Models - Only)
The flue outlet and combustion air inlet
terminate in the same pressure zones, but
when installed with a negative draft,
Category I vent system, does not meet the
specifications of a direct vent system.
DirectAire Horizontal
DirectAire Horizontal vent systems are
installed with the flue terminating at the
sidewall, using Category IV vent materials,
and a separate combustion air inlet pipe at
the rooftop, or at the sidewall to draw air
from the outdoors. The flue outlet and
combustion air inlet terminate in different
pressure zones.
The maximum installed length of the
combustion air inlet pipe and flue gas vent
pipe must not exceed 50 equivalent feet
(15.2m) in length per pipe.
The flue and air inlet sizes for DirectAire
Horizontal systems with Rooftop Air Inlet are
listed in TABLE E. This venting option uses a
rooftop air inlet constructed from materials
purchased locally by the installer or a
sidewall air inlet purchased from the
manufacturer, and a sidewall vent
termination purchased from the manufacturer.
The part numbers for the required sidewall
vent cap kit are listed in TABLE C. The part
numbers for the required sidewall air inlet
cap kit are listed in TABLE D.
DIRECT VENT SYSTEMS
A Direct Vent system uses a flue to the
sidewall or rooftop with a separate
combustion air inlet pipe to the outdoors.
The Direct Vent system terminates the flue
and the combustion air inlet pipe on the
same surface and in the same pressure zone
in one of two configurations.
(1) The flue on the rooftop and combustion
air inlet on the rooftop. (FIG. 17)
(2) The flue on the sidewall and combustion
air inlet on the sidewall. (FIG. 18)
Direct Vent systems require the installation of
specific venting materials. Rooftop flue gas
termination caps and combustion air inlets
must be purchased locally. Sidewall flue gas
termination caps and combustion air inlets
must be purchased from the appliance
manufacturer as per CSA International
requirements.
Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900 15
Lochinvar
(FIG. 14) DIRECTAIRE VERTICAL W/ROOFTOP AIR INLET
(FIG. 16) DIRECTAIRE HORIZONTAL W/ SIDEWALL AIR
INLET IN A DIFFERENT PRESSURE ZONE
(FIG. 15) DIRECTAIRE HORIZONTAL
W/ ROOFTOP AIR INLET
NOTE:
Units with ON/OFF
burner controls utilize
Category IV vent
material when
installed in
a Direct Vent
configuration.

16 Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
Lochinvar
A Direct Vent system MUST have a dedicated
air inlet pipe. Air inlet pipes for multiple units
CANNOT be combined.
Direct Vent Vertical System
A Direct Vent Vertical System is installed with a
Category IV flue and a separate air inlet pipe
to draw combustion air from the outdoors. The
combustion air inlet cap and flue gas vent cap
must be located on the same rooftop surface
and in the same pressure zone. The maximum
installed length of the sealed combustion air
inlet pipe and positive pressure flue gas vent
pipe must not exceed 50 equivalent feet
(15.2m) in length per pipe.
Direct Vent Vertical Combustion Air Inlet
The vent termination and air inlet cap for
rooftop installation are not supplied by the
manufacturer and must be purchased locally.
The vent termination requires an all weather
vent cap and the air inlet cap consists of two
90° elbows installed at the point of
termination for the air inlet pipe.
Direct Vent Horizontal Systems
A Horizontal Direct Vent system is installed
with a Category IV flue and a separate air
inlet pipe to draw combustion air from the
outdoors. The combustion air inlet cap and
flue gas vent cap must be located on the
same sidewall surface and in the same
pressure zone.
The maximum installed length of the
sealed combustion air inlet pipe and
positive pressure flue gas vent pipe must
not exceed 50 equivalent feet (15.2m) in
length per pipe.
Direct Vent Horizontal Combustion Air
Inlet and Vent Termination
The connection from the appliance flue outlet
to the sidewall vent cap must be made with
Category IV type vent materials for both
ON/OFF and Modulating models. The
sidewall vent cap and air inlet cap must be
purchased from the appliance manufacturer
as per CSA International requirements.
The Category IV flue from this appliance
CANNOT be combined with the vent from
any other appliance. The flue must be a
dedicated stack and must have all vent joints
and seams sealed gastight.
(TABLE F) – DIRECT VENT HORIZONTAL KITS
MODEL AIR VENT
NUMBER FLUE INLET KITS
PF0501 7" 5" HDK3033
PF0751 9" 5" HDK3034
PF1001 10" 6" HDK3035
PF1300 12" 6" HDK3036
PF1500 8" 6" HDK3021
PF1700 8" 8" HDK3022
PF2000 10" 8" HDK3023
(FIG. 18) DIRECT VENT HORIZONTAL
(FIG. 17) DIRECT VENT VERTICAL

Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900 17
Lochinvar
Locally purchased or fabricated sidewall vent
caps and air inlet caps must not be used. The
part numbers for the required sidewall vent
cap and air inlet cap kits are listed in TABLE
F. Each kit includes the vent cap and air inlet
cap for installation on an exterior sidewall for
a single appliance only.
GAS SUPPLY
The gas pressure regulator supplied is for
low pressure service. If upstream pressure
exceeds 6 oz. (10.5" water column), an
intermediate gas pressure regulator, of the
lock up type, must be installed.
The gas line should be a separate line
direct from meter, unless the existing
gas line is of sufficient capacity. Verify
pipe size with your gas supplier.
A trap (drip leg) should be provided in the
inlet gas connection to the water heater.
A manual main gas shutoff valve is
provided outside the jacket, upstream
of the main gas valve.
In Canada, derated10% from 2,000 -
4,500 ft., over 4,500 ft. derate must be
in accordance with local authorities.
Consult factory for installations at
higher elevations.
High Altitude Applications
Atmospheric pressure decreases as the height
above sea level increases. At any altitude
above sea level, a cubic foot will contain less
gas than a cubic foot at sea level. Thus, the
heating value of a cubic foot of fuel gas will
decrease as height above sea level increases.
Specific gravity of a gas with respect to sea
level also decreases with altitude. These
changes in heating value and specific gravity
tend to offset each other. However, as
elevation above sea level is increased, there
is less oxygen per cubic foot of air. Therefore,
heat input rate should be reduced in an
appliance above 2000 feet; ratings should
be reduced at the rate of 4 percent for each
1000 feet above sea level.
1.
2.
3.
5.
4.
(TABLE G) GAS SUPPLY PIPE SIZING
Length of Pipe In Straight Feet
Nominal Iron
Pipe Size, Inches 10 20 30 40 50 60 70 80 90 100 125 150 175 200
369 256 205 174 155 141 128 121 113 106 95 86 79 74
697 477 384 328 292 267 246 256 210 200 179 164 149 138
1,400 974 789 677 595 543 502 472 441 410 369 333 308 287
2,150 1,500 1,210 1,020 923 830 769 707 666 636 564 513 472 441
4,100 2,820 2,260 1,950 1,720 1,560 1,440 1,330 1,250 1,180 1,100 974 871 820
6,460 4,460 3,610 3,100 2,720 2,460 2,310 2,100 2,000 1,900 1,700 1,540 1,400 1,300
11,200 7,900 6,400 5,400 4,870 4,410 4,000 3,800 3,540 3,300 3,000 2,720 2,500 2,340
23,500 16,100 13,100 11,100 10,000 9,000 8,300 7,690 7,380 6,870 6,150 5,640 5,130 4,720
Maximum capacity of pipe in thousands of Btu per hour for gas pressures of 14 Inches Water Column (0.5 PSIG) or less and a pressure
drop of 0.05 Inch Water Column (NAT GAS, 1025 Btu per Cubic Foot of Gas, based on 0.60 specific gravity gas).
11 /4
3
/4
11 /2
1
3
4
21
/2
2
EXAMPLE OF
HIGH ALTITUDE
APPLICATIONS
For example, if a unit’s
input is 1,000,000 Btu/hr
at sea level, the rated
input at 4000 feet of
elevation can be calculated
by derating input 4% per
1000 feet above sea level.
[Btu/hr Input]
[1.00 - (Elevation / 1000'
x 0.04)] = Btu/hr Input at
Specified Elevation
[1,000,000] [1.00 -
(4000' / 1000' x 0.04)]
= Btu/hr Input at 4000'
Elevation [1,000,000]
[0.84] = 840,000 Btu/hr
Input at 4000' Elevation

GAS BLEEDS AND VENTS
All bleeds and vents from valves and
regulators are vented to the atmosphere,
outside of the fan pressurized inner
chamber. Local codes may require
routing of these bleeds and vents to the
atmosphere, outside of the building.
WATER CONNECTIONS
Inlet and Outlet Water Connections
For ease of service, install unions on inlet
and outlet of the water heater. The
connection on the unit marked "Inlet" should
be used for return water from the storage
tank. The connection on the header marked
"Outlet" should be connected to the inlet of
the storage tank. (See Appendix A for
Water Heater Piping Diagrams).
LOW WATER
TEMPERATURE DELIVERY
A number of water heating applications may
require delivered water temperature in a
system below 140°F. Systems such as
nursing homes and hospitals would be
examples of this type of system. A water
heating system that will be operated at less
than 140°F must use a mixing valve on the
outlet side of the storage tank in order to
ensure that the products of combustion do
not condense inside the combustion
chamber of the water heater. The mixing
valve allows the water heater to operate
above 140°F to protect from condensation,
while still allowing a delivery of colder water
to the system fixtures. Also inherent in this
design is the protection of occupants from
water containing bacteria such as
Legionella. Legionella can be significantly
reduced in the water storage vessel by
heating the water to a minimum of 140°F.
See Appendix A for piping details.
WATER VELOCITY CONTROL
IMPORTANT
To ensure proper velocity through the heat
exchanger, it is necessary to regulate the
temperature rise across the heat exchanger
from inlet to outlet. (This must be done on
initial installation and periodically
rechecked). With the correct temperature
rise across the heat exchanger (See TABLE I),
you may be assured of the proper velocity in
the tubes and long life and economical
operation from the water heater.
18 Lochinvar DESIGNER’S GUIDE POWER-FIN WATER HEATER 615-889-8900
Lochinvar
(TABLE H) – INLET GAS PRESSURE REQUIREMENTS
NATURAL LP
PF0501 Max. Allowable 10.5" 13"
- 1300 Min. Allowable 4" 11"
PF1500 Max. Allowable 10.5" 13"
- 2000 Min. Allowable 4" 4"
(TABLE I) – REQUIRED TEMPERATURE RISE
MODEL TEMPERATURE
NUMBER RISE (°F)
PF0501 11
PF0751 17
PF1001 23
PF1300 30
PF1500 29
PF1700 33
PF2000 39
NOTE:
Care should be
taken to measure
temperature rise and
maintain proper water
velocity in the heat
exchanger.