Heaters .................................... 4

C.
Unit Features Vertical Delivery Unit Heaters ........................................ 5

D.
Unit Features Power Throw Horizontal Delivery Unit Heaters .......... 6

E.
Options and Accessories ......................................................................... 7

F.
Power Code Descriptions, Sound Classifications, Control Sequence ..... 8
II. Performance
Data
A.
Breeze
TM
AccuSpec Sizing and Selection Program ................................ 9
B.
Steam
Conversion
Tables
...................................................................... 10

C.
Steam Performance Data Standard Models ....................................... 13

D.
Steam Performance Data Low Outlet Temperature Models ............... 14

E.
Steam Conversion Tables Example Calculations ............................... 15
F.
Hot
Water
Conversion
Tables
................................................................. 16

G.
Hot Water Performance Data Standard Models ................................. 19

H.
Hot Water Performance Data Low Outlet Temperature Models .......... 20

I.
Hot Water Conversion Tables Example Calculations .......................... 21

J.
Maximum Mounting Heights for Outlet Accessories .............................. 22

K.
Vertical Air Outlet Accessory Dimensions, Motor Data ......................... 23
III. Dimensional
Data

A.
Dimensions Horizontal Air Delivery Models ........................................ 24

B.
Dimensions Vertical Air Delivery Models ............................................ 25
IV. Model
Identification ....................................................................................... 26
V. Specifications ................................................................................................ 27
2
Refer to page 9 for information regarding the
Breeze
TM
AccuSpec Sizing and Selection Program
Canadian
Registered
heat exchangers
CRN
OH 9234.5 3
DESIGN BENEFITS
Application, Design, Construction Overview
Product Selection
Modine offers steam/hot water unit heaters in a wide range of ratings from as low as 11,300 Btu/hr for hot water and as high as
952,000 Btu/hr for steam, based on standard conditions. Three different air delivery configurations are available: horizontal, vertical
and Power Throw offering high velocity horizontal air delivery.
Simplified Selection
All ratings are shown as Btu/hr, eliminating the need to convert from EDR. This simplifies the matching of unit ratings to building
heat loss. Modine model numbers reflect MBH ratings for standard steam conditions, simplifying unit selection.
Reliability
All motors are totally enclosed. All single phase and explosion proof motors include internal overload protection to protect the motor
from insulation damaging heat, resulting in longer motor life.
Ease of Installation/Maintenance
All units include an electrical junction box, either integral to the motor or mounted on the unit casing. This allows for easy electrical
connection. Different suspension options are available for most units. All units are component tested for proper motor function and
the coils are leak tested under pressure to ensure proper function when the unit arrives at the jobsite.
Fins on all units are vertical to limit build-up of foreign particles, prolonging periods between cleanings. Fins on vertical and Power
Throw units are exposed for easy cleaning.
Application Flexibility
Horizontal and vertical units are available in standard and low outlet temperature (LOT) models. LOT models have special coils with
fewer fins per inch reducing the output rating of the unit heater. LOT models are typically used where steam pressure exceeds 30
PSI and mounting height is critical, but can be used in any application requiring a lower outlet temperature. LOT models are also
well suited for dirty environments where the increased fin spacing decreases the build-up of foreign particles on the coil.
Horizontal and Power-Throw units are furnished with louvers for directional control of heated air. Vertical units are available with
various louver, truncone, cone-jet and anemostat deflector options to accommodate many different air distribution patterns.
Side piping connections on the HC horizontal air delivery model allow for low clearance installations.
Explosion proof motors are available for use in hazardous areas. Canadian Standards Association (CSA) requirements state that
explosion proof units may not be used with a fluid temperature in excess of 329°F or pressures greater then 87 psig and still
maintain their explosion proof rating for the National Electric Code ignition temperature rating of T3B for grain dust. See page 8 for
additional details.
Quiet Operation
Quiet operation is assured through the use of carefully selected motors, fans and scientifically designed venturi fan shrouds.
Attractive Styling
HC models (all sizes) and HS models (258-340) have squared off corners for a clean, defined appearance. HS models (18-193)
have rounded corners and ribbed sides for strength, providing an aesthetic appearance without exposed fasteners. Vertical units
and Power Throw units have a pleasing circular symmetry.
All unit casings are treated for corrosion resistance and finished with a gray-green baked-on, high solids paint. 4
DESIGN BENEFITS
Unit Features Horizontal Delivery Unit Heaters
Horizontal delivery unit heaters are the most popular of all
types. These units are ideal for heating buildings with large
open areas and low ceilings. They are used to counter heat
loss along outside building walls, especially where windows
are present.
Horizontal units operate with either steam or hot water
systems.
Features that enhance the popularity of the horizontal
delivery unit heater are:
Lower Installation/Maintenance Cost
These units are compact and lightweight, requiring fewer man-hours to install.
Integral junction box for ease of electrical wiring.
HS units have steel top and bottom supply and return connections. This permits the unit to be rotated 360° without piping
changes.
HC units have copper side supply and return connections. This permits the unit to be installed in low clearance areas.
Both units have a 2-piece casing for easy coil access.
All models have tapped holes for suspension by threaded rod or optional pipe hanger adapter kit, except HS-18 and HS-24
which mount directly to and are supported by the supply and return piping.
Failure Resistant Coil
Serpentine copper tube design has high resistance to thermal shock, even under high steam pressures.
Absence of headers eliminates potential leaks and increases coil face area without increasing overall size of unit.
Designed for greater water carrying capacity with lower friction loss.
Complete Line of Low-Outlet Temperature (LOT) Models
Ideally suited for applications where steam pressures exceed 30 PSI and critical mounting height restrictions exist.
Due to special coil design, the discharge air temperatures of LOT models are approximately the same as those of standard
units operating on lower steam pressures.
Air distribution is increased through higher air volume/velocity.
Ideal for use in dirty atmospheres because greater fin spacing increases resistance to foreign particle build-up.
Heat Throw Down to the Floor
Modine design assures the correct relationship between air temperature, velocity and volume for greater heat throw.
Air is delivered to the floor at maximum mounting height, increasing comfort and reducing fuel costs.
Simplified Selection
Standard model numbers indicate MBH rating at 2-lb. steam pressure and 60°F entering air temperature.
Figure 4.1
Unit Features
HS MODEL
HC MODEL
Connections Female type permits direct connection of unit heater to the piping and eliminates the need for additional
fittings.
Vertical Fins Less opportunity for dust and dirt to collect. Reduces cleaning. Fins die-formed for added strength and
heat transfer.
Coil All air passes through coil. Heating is uniform. Design assures maximum control over air delivery and temperature
of air leaving the heater. Aluminum fins die-formed for added strength increased heat transfer. Fins mechanically bonded
to serpentine copper tube.
Motor All motors are totally enclosed. Single phase and explosion-proof types include built in thermal overload
protection. Built by reputable manufacturers to NEMA standards. Selected and tested for operation on specific unit heater
models. All motor wiring is terminated in an electrical junction box either supplied on the unit heater casing, or as an
integral part of the motor.
Fan Lightweight. Blades accurately balanced and pitched to move air quietly and positively with minimum power
requirement.
Deflector Blades Adjustable horizontal air-deflector blades are standard. Vertical blades are also standard on models
HC/HS-258, HC/HS-290 and HC/HS-340 and are optional on other models. Both horizontal and vertical blades are
illustrated.
Safety Fan Guard Standard equipment. Bolted to rear casing, steel rod fan guard completely surrounds the fan offering
constant protection.
Casings Baked-on gray-green high solids paint is applied over rust-and corrosion-resistance-treated steel for long life. 5
DESIGN BENEFITS
Unit Features Vertical Delivery Unit Heaters
Vertical delivery unit heaters are ideal for heating buildings with high ceilings or areas
that require the heater to be mounted above obstructions such as craneways. Selection
from a variety of heat throw patterns is made easy by choosing from four types of air
deflectors. Heat throw patterns range from a high-velocity narrow jet to a g