Trane UH-PRC001-EN User Manual

Propeller Unit
Heaters/Unitary

17.4 to 705.6 MBh
Two Versatile Models - Various Sizes
Easy Installation

October 1999

UH-PRC00 1 -EN

Introduction

The Industrial Designed Model P Unit Heater

The square, compact design of the
Model P and rectangular Model S allow
easy handling and installation. In most
cases, only one person is needed to
carry a unit. And because both feature
compact Sigma-Flo
lightweight, making them easy to hoist
and put into place.

©American Standard Inc. 2000

®

fins they’re

The Clean-Line Appearance of the Model S Unit Heater

What’s more, the Model P can be stored
standing on end. This means several
units can be loaded on a single skid for
moving from one point to another. Trane
maintains a complete stock of both
Model P and S units that are available to
ship anywhere in the United States.

Y et, the benefits of this compact design
go beyond ease of installation. They
continue with attractive styling. The
Model S unit’s simple, clean-line
symmetry and the Model P unit’s classic
modern shape enhance any industrial
facility.

UH-PRC001-EN

Contents

Introduction
Featur es and Benefits

Application Considerations
Selection Procedur e

Manual Selection Procedure
Model Number Description

P erformance Data
Electric P o wer
Dimension and W eights
Mechanical Specifications

2
4

8

11

19

21
23

44
47
50

UH-PRC001-EN

3

Features and
Benefits

Two Units in One – the Versatile Model P

The T rane Model P can be quic kly field
converted from standard to low final
temperature PL design simply by
removing the unit’s patented knockout
air ports. This unique two-in-one design
allows the stocking wholesaler to cut
inventories in half and still meet most
customer application requirements.

T rane propeller unit heaters feature the
largest selection of standard sizes from
any line in the industry . In fact, vertical
Model P and horizontal Model S unit
heaters provide enough ‘of f-the-shelf’
selections to fit almost any application.
The versatile two-in-one Model P is
available in 15 sizes with capacities from
41 .3 MBh to 705.6 MBh while the
companion standard and bypass Model

The Space-Saving Model S

The Model S features attractive,
functional styling in a space-saving,
compact design.
In addition, T rane of fers an exclusive
bypass Model S design to meet low final
temperature, high cfm requirements. This
design uses a modified coil which allows
some of the air to flow over the top of the
coil without being heated. This cooler
band of air prevents the heated air from
rising so warm air throw is increased
while efficiency is improved.

S is available in 29 sizes with the
capacities from 17.4 MBh up to 404 MBh.
Both are designed for durability,
attractiveness and compactness. These
features combined with economical
operation, give strategically sized T rane
unit heaters an edge unmatched by any
other manufacturer.

Put Heat Where It’s Needed

Exclusive louver fin diffusers featured on
T rane unit heaters put heat where it’s
needed.

Patented Trane louver cone diffusers allow
directional flexibility of heated air.

Trane Model S features louve red disc har ge as
standard.

These patented T rane dif fusers provide
an unlimited combination of air diffusion
patterns as well as greater air throw
distance. In fact, when the louver cone
diffuser is added to the Model P, up to 45
percent greater air throw distance is
possible.
On Model S units, the combination of
horizontal louver blades and patented
vertical diffuser fins provide four­directional control of air delivery.
Optional low cost louver fin diffusers can
be adjusted to provide up to 25 percent
more air throw.

UH-PRC001-EN4

Features and
Benefits

The Model S Coil

The Model S unit heater features a
unique single tube serpentine coil. This
compact, efficient coil has piping
connections at the back for added space
savings, convenience and appearance.
Model S single circuit coils use threaded
connectors at the back of the unit.

The Model P Motor

The Model P motor is mounted below
the top panel inside the heater casing.
This reduces unit height and permits the
unit to be installed closer to the ceiling
for added headroom.

Compact Design

T rane designed Model S and P propeller
unit heaters for easy installation and low
maintenance. The Trane Sigma-Flo
design allows coil size to be reduced
while maintaining high capacity
performance equal to larger flat-fin coils.
Reduced size and weight makes T rane
unit heaters easy to handle and install.

Rectangular Draw -Thr u Coils

The Model P draw-thru coils use short
lengths of steel pipe threaded for supply
and return connections. These features
make piping connections much easier
for the installer.

®

fin

5UH-PRC001-EN

Model P

A

Exclusive T rane designed aluminum fans
provide smooth, nonsurge performance.
This, in turn, provides efficient, quiet
operation.

B

High performance Sigma-Flo
one-row coil have more efficient heat
transfer characteristics than flat fin coils.

C

Steel pipe headers are electrically
induction-brazed to coil tubes.

D

Top panel features knockout air ports
that, when removed, convert the unit
from standard to low final air
temperature, higher cfm operation.

E

Bottom plate provides drawn fan orifice
to assure smooth airflow.

F

Sturdy motor mounts absorb vibration
and anchor the motor securely .

G

Totally enclosed industrial designed
motors feature built-in overload
protection.

®

fins in a

Features and
Benefits

C

B

C

G

A

F

G

F

D

B

E

A

Model S

A

Exclusive, compact one-row
serpentine coil features high
performance Sigma-Flo fins.

B

One-piece wraparound casing with
picture-frame front panel combines
attractiveness with durability.

C

Heavy-gauge, one-piece bac k panel
can be easily removed for quick coil
access.

E

H

D

D

Rear connections and a compact
design provide more headroom than
conventional units.

E

Sturdy fan guard provides stronger
motor mount and quiet operation.

F

Unique coil supports anc hor coil
tubes without restricting expansion.

G

T rane horiz ontal louvers stay in
position with the exclusive louver
keeper design.

H

Totally enclosed industrial design
motors feature built-in overload
protection.

UH-PRC001-EN6

Model P

Simple Hanger and Piping Connections

The Model P uses weldnut type hanger
connections, while the Model S uses a
nutsert type hanger connection. Hanger
rods screw easily into threaded anchor
points. Piping connections can be made
equally as easy. Model P units pro vide
threaded connections for inlet and outlet,
top and bottom.

Features and
Benefits

Model S

Fully A ccessible f or Easy Maintenance

Model S and P unit heaters are fully
accessible for maintenance. Only four
main bolts are needed to disassemble
the Model P. And when quick access is
needed, the Model S features a
one-piece back that can be easily
removed and slid over pipes without
breaking connections.
Motors can also be easily removed. Both
units feature totally enclosed motors
with thermal overload protection. As an
added benefit, Model P fan-motor
assemblies can be conveniently
removed from below through the fan
outlet.

External Couplings

The Model S provides threaded
connections for supply and return on the
back of its casing. In addition, bac k
connections reduce the amount of space
needed for installation.

7UH-PRC001-EN

General Rules

In locating or spotting Trane Propeller
Unit Heaters – either the Model S
Horizontal or Model P Projection Unit
Heater – the following general rules
should be considered.
1 . Spot units at points of greatest heat
loss. Blanket outside doorways
effectively and provide ample coverage
for exposed window areas.

2. Units, especially in the case of the
Model S Horizontal Unit Heater , should
be arranged to blow toward or along
exposed walls, preferably striking the
wall at a slight angle so that the heated
air exerts a wiping effect along the w all.
Balance of units required to supply Btu
requirements should be spaced
strategically in balance of the area.

3. Unit heaters should be arranged to
blow into open spaces such as aisles and
not directly at any worker. An exception
to this rule involves the use of the Model
P Unit Heater equipped with the Louver
Cone Diffuser . This combination can be
used effectively over closely spaced bins
or machines without regard for open
space. But not even the Model P Unit
Heater with Louver Cone Diffuser should
be in such close proximity to the workers
to cause discomfort.

4. The T rane solid-state speed control will
provide maximum capacity flexibility and
quieter operation. Note that this speed
controller is available only on selected
models.

5. Mounting heights and distance of
throw recommendations as given
elsewhere in this catalog should be
carefully observed.

6. In the case of Model P Units, they
should be spotted so that they will most
effectively prevent stratification of
excessively warm air at the ceiling. By
carefully observing this rule, this type of
unit may be used between seasons to
tap waste heat at the ceiling and drive it
down to occupied zones, thereby
eliminating the need for added heat on
the system.

7. Do not spot units close to any
obstruction that will impede the full and
natural air delivery of the unit.

Typical Factory

In the typical industrial building, where
ceilings are high, Model P Unit Heaters
may be used without diffusers.

Application Considerations

Figure A C-1 – The floor plan and elevation of a typical industr ial building showing ho w a
Trane Unit Heater System will heat var ious par ts. Where ceilings are high in the main
manufactur ing section, l arg e Projection Heat ers without dif fusers are used. Where ceilings
are exceptionally high, as in cr ane bays, Model P Units with Louver Cone Dif fusers pr ovide
up to 45% greater thr ow t o top the “ceiling heat r eservoir.” Model P Units with half closed
Louver Cones blanket doorwa ys. Model S Units with Louver Fins blank et windows.

In plants where the ceilings are
exceptionally high, such as in crane bays
as illustrated in Figure AC-1, Model P
Units with Louver Cone Diffusers can
increase the downward projection of
heat by as much as 45% over units
without diffusers.
Model P Units with the Louver Cone
Diffusers can also be used to blanket
doorways effectively, as shown in Figure
AC-1 by simply adjusting half of the
louvers vertically, and half closed.
Model S horizontal-type units are ideal
for mounting in plant areas where
ceilings are low. In fact, due to the

extremely small height of the Model S,
and because all piping connections are
made at the back of the unit, the Model S
provides a greater saving in headroom
than other horizontal unit heater makes.
As illustrated in Figure AC-1, the Model S
Unit Heaters may be mounted
conveniently from the ceiling, or from
building structural supports and beams.
With Louver Fin Diffusers, they are ideal
for blanketing windows, and Model S
“Bypass” Unit Heaters, provide further
flexibility of application where greater
throw and more effective distribution of
air in the living zone is required.

UH-PRC001-EN8

Application
Considerations

General Notes

The following general notes on piping
propeller unit heaters are presented
based on competent engineering and
installation practice:
1 . Suspend unit heaters securely with
provisions for easy removal.

2. Make certain units hang level vertically
and horizontally .

3. Provide for expansion in supply lines
(note swing joints in suggested piping
arrangements).

4. Provide unions adjacent to unit heaters
in both supply and return laterals. Also
provide shut-off valves in all supply
laterals.

5. Use 45' angle runoffs from all supply
and return mains.

6. Provide at least 7" (more if necessary)
clearance above tops of Model P
Projection Unit Heaters. Motors are
removable from below on all sizes.
It is desirable to form dirt poc kets with
pipe of the same size as the return
tapping of the unit heater. Pipe in the
branch-of f should be the same siz e as the
tapping in the trap. Beyond the trap, the
return lateral should be increased one
size to the return main.

Hot Water System – Using Cir culating
Pump

Overhead supply and return mains are
used with bottom connections to mains.
Manual vent (pet cock) is used at high
point on return main. Automatic air vent
may be substituted if desired. Refer to
Figure AC-2.

Figure AC-3

High Pressure Steam Syst em

Overhead supply main is used with
lower return main. Where steam
pressure fluctuates over a wide range, a
swing chec k valve should be placed in
the return lateral between strainer and
bucket trap to prevent reverse flow of
condensate of flash steam when
pressure drops suddenly. Top of buc ket
trap must be located below return outlet
of coil for complete drainage of
condensate. Refer to Figure A C-3.

Figure AC-2

9UH-PRC001-EN

Application
Considerations

Figure AC-4

Table AC-1 - Model P Coil F ace Area

Unit Numbers Fin Area In Sq. Ft

42-P & P-L 1 .20
64-P & P-L 1 .49

80-P & P-L 1 .98
102-P & P-L 3.28
122-P & P-L 3.28
146-P & P-L 3.88
166-P & P-L 4.85
202-P & P-L 4.85
252-P & P-L 6.52
280-P & P-L 6.52
336-P & P-L 6.52
384-P & P-L 7 .82

500-P & P-L 8.72
600-P & P-L 11.63
720-P & P-L 13.08

Table AC-2 - Supply and Retur n Sizes at 2 Psi

Capacity In Lbs. Of Size Of Size Of

Steam Per Hour Supply Gravity Return

39 1” 3/4”

87 1 1/4” 3/4”
134 1 1/2” 1”
272 2” 1 1/4”
449 2 1/2” 1 1/2”
822 3” 2”

Note: This table is based on 1/2 lb. drop per 100 ft. of
equivalent run of steam line and approximately 1/4 lb. drop
in the return line per 100 ft. increase steam run-outs one
size if more than 8 ft. long.

Figure AC-5

Figure AC-6

V apor or V acuum S ystem

Lower supply and return mains are used.
Piping should be similar to that used with
overhead supply main if it is separately
vented and trapped. Bottom supply for
steam mains may be used if steam is dry.
Refer to Figure A C-4. F or proper pipe size,
refer to T able AC-2.

Hot Water System with Cir culating
Pump

Lower supply and return mains are
shown. Overhead supply and return
main connections, similar to those in
Figure AC-2 may be used. The automatic
air vent is shown here but a manual vent
(pet cock) may be substituted. Refer to
Figure AC-5.

High Pressure Steam S ystem

Overhead supply and return mains are
used. The top of the bucket trap must be
located below bottom return outlet of coil
for complete drainage of condensate.
Refer to Figure A C-6.

UH-PRC001-EN10

Selection Pr ocedure

Trane Propeller Unit Heaters

Both Model S and Model P Propeller
Unit Heaters are ideally suited to such a
wide variety of installations that there
can be no hard and fast rules regulating
their selection.
In determining the type and size of the
units for any building, the following
points are generally considered:

BTU Requirements

While the choice of units depends upon
several important factors, the total Btu
requirement is usually determined first.
In calculating heat loss, methods as
recommended by the ASHRAE Guide
may be used, or any other procedure
which is known to be acceptable.

Type of Building

Once the total Btu requirement is known,
the type of building together with its
architecture and its purpose is
considered.
In the many cases where a combination
of space characteristics is found, a
combination of Model S and Model P
Unit Heaters may be used to create the
most satisfactory heating system.
The Model P Unit Heater has the natural
ability to tap the reservoir of heated air
which collects at the ceiling level and
return it to active service in the floor
zone.
The Model P can be used on either high
or low ceilings. From high mounting
positions the Model P will allow ample
clearance for moving objects and can
project heat down into occupied areas
regardless of obstacles which would
restrict the flow of air from horizontal
units.
From low mounting positions the Model
P, with proper diffusion, can be used
without disturbing nearby occupants
with direct blasts of high velocity heated
air, or requiring return lines so low as to
leave insufficient head room.
The superior horizontal action of the
Model S, on the other hand, is ideal for
creating a wiping effect of warm air
along exposed walls which neutraliz es
drafts at their source, beaming heat
down narrow aisles and production
lines, and blanketing large windows,
doors and other points of high heat loss.

Spacing of Units

It is the usual practice to divide the
building into areas with like exposures,
or in relation to heat load distribution
desired.
In general, Model S Unit Heaters may
be selected for buildings where direct
horizontal air currents are desired and
where there are no obstacles to
interrupt the flow of air from the
heaters.
Model P Unit Heaters are successfully
used where high or low mounting
heights are required and should
ordinarily be specified with diffusers,
depending upon the mounting height
and application.

Mounting Heights

maximum

The

height is determined by the outlet
temperature of the air, the outlet
velocity, the cfm for whic h the heater is
designed, and if a diffuser is used – the
setting of its blades.
The higher the outlet temperature of
the air, the more dif ficult it is to force it
down into the living zone.
The cfm also affects the mounting
height as a large volume of air will
travel farther than a small volume
under the same initial conditions of
temperature and velocity.
In the preliminary planning stages, it is
well to remember that the lowest
possible mounting height is desirable in
order to get the most heat down to the
floor line and to allow the greatest
possible diffusion adjustment to
provide tailor-made distribution for
each area.

effective mounting

In providing for the use of diffusers
please remember, adjustment of a
Louver Cone Diffuser to deflect the air
toward the horizontal immediately
lowers the mounting height limit.
Adjustment for lateral deflection with
the Louver Fin Diffuser shor tens the
distance of throw.

Diffusion

The use of T rane L ouver Cone or
Louver Fin Diffusers influences the
selection of units in two principal ways:
First: It is seldom necessary to install

oversized heaters to extend the
maximum effective mounting height of
the Model P or the distance of throw of
the Model S. Conversely, Trane Diffusers
enable extremely low mounting since the
adjustable blades direct heat where it is
wanted without creating uncomfortable
hot spots near the units.

Second: Af ter the original selection has
been made, units may be located with
confidence because adjustments in heat
distribution are possible to
accommodate future changes or
unforeseen draft conditions.

Air Changes

Better diffusion and more even
temperatures can be maintained in a
heated space when the rate of air
recirculation through the heaters is
relatively high. For buildings where large
numbers of people are engaged, it is
desirable to provide for a greater number
of air changes than for sparsely occupied
areas.
A greater number of small units are used
where wide diffusion and even
temperatures are necessary. A few
centrally located units of large capacity
would be used where there are few
occupants.

Comfort Conditions and Econom y

Air circulation, diffusion and spacing of
units are closely related to economy and
comfort in the selection of unit heaters.
The more units used to provide the
required number of Btu’s, the more
comfortable will be the conditions for
personnel. On the other hand, a few
large units can be selected to provide
plenty of heat at low first cost, but may
be slower in response and thorough
distribution of heat.
Here again, adjustable diffusion
equipment can go a long way toward
saving the buyer first cost expense while
still providing completely satisfactory
comfort conditions.

11UH-PRC001-EN

Selection
Pr ocedure

Formula

The following formula is used to arrive at
final air temperature volume when 70 F
(Standard Air Basis) is known or vice
versa:

Cfm at final temp. =
Cfm at 70 F x

Cfm at 70 F =
Cfm final air x

Determining Special Steam Capacities

Where capacity of the unit under
standard conditions is known – 2 lbs.
steam, 60 F entering air – and it is
desired to know the capacity of this
same unit under different steam and air
conditions, follow instructions given in
Example 1 below.

Where a set of conditions is given – Btu,
temperature rise, final temperature, cfm,
steam pressure available, etc. Refer to
Example 2.

Useful Data

Btu

= Sq. ft. of radiation (EDR)

240
Sq. ft. of radiation =Lbs. of condensate

Btu

Latent heat

460 + Final temp.

460 + 70

460 + 70

460 + Final temp.

4 per hour

= Lbs. of water per hour

Example 1

Given: Model 60S Horizontal Propeller
Unit Heater with a rated capacity of
60,500 Btu at 2 lbs. steam with 60 F
entering air.

Desired: Capacity of this unit using
15 lbs. steam and 40 F entering air.

Under 40 F and across from 15 lbs. in
SP-2, page 14, we find the factor 1.34.
60,500 x 1.34 = 81,070 Btu per hour .

Equivalent Direct Radiation

If working in EDR, rather than Btu,
multiply the EDR by the same factor in
the same way. Thus:

252 (From Table 3) x 1.34 =

81,070

338 sq. ft. or

Determining Amount of Condensate

To determine the amount of condensate,
divide the capacity in BTU by the latent
heat of steam:

81,070

945

945 = Latent Heat of Steam at 15 psi.

240

= 86 lbs per hour.

(See Table SP -9, page 18.)

Determining Final Temperature

Final temperature of air leaving T rane
Unit Heaters may be determined as
follows:

Inlet Air T emp. + Btu rating = FinalTemp

Cfm at 70F x 1 .085

Inlet Air Temp. 40F + 81,070 = FinalTemp

815(from table 3) x 1 .085

Example 2:

Problem: A Trane Model S Horizontal
Unit Heater is desired to deliver 280,000
Btu per hour in a garage where
ventilation is required. Entering air
temperature is 40 F. Steam at 30 lbs.
pressure is available. Temperature to be
maintained is 70 F.

Solution: Under 40 F and across from 30
lbs. in Table SP-2 page 1 4, find the factor
1 .51.

Equivalent capacity of required unit at
2 lbs. steam 60 F entering air is

Required Btu per hour = 280,00 =185,400

F 1 .51 Btu

From Table SP -3, page 15, select a
Number 186S Unit Heater with a
capacity of 185,200 Btu per hour with
standard coil, and at 2 lbs. steam and 60

F entering air.
Cfm x Temp. rise x 1.085 = Btu.
Specific heat of air (70 F) = .241
Specific weight of one cubic foot of air

(70 F) =.075.
Cfm x 60 = cfh.
Therefore, .241 x .075 x 60 = 1 .085

The capacity of this unit at 30 lbs. steam

and 40 F entering air is

1 .51 x 1 85,200 = 279,650 Btu per hour.

Surplus Capacity

While the ventilation load is being

handled, any air entering the space over

the desired room temperature should be

considered in the heating calculations.

This surplus capacity can be found by

multiplying the difference between the

final temperature leaving the heater and

the room temperature to be maintained

by 1 .085 and that by the cfm. That

amount of heat can be used to offset

heat losses.

UH-PRC001-EN12

Selection
Pr ocedure

Model S Nomenclature
UHS A 0 1 8 S 2 E A A 1 T A W D A D B E

123 4 5 6 7 8 9 10 11 12 13 1 4 1 5 1 6 17 18 19 20 21

Digits 1,2,3 – Product T ype

Digit 4 – Development Sequence

Digits 5,6,7 – Unit Size

Digit 8 – Coil T ype

S = Hot Water or Steam
W= Hot W ater with Turbulators

Digit 9 – Fin Series

2 = 132
8 = 108

Digit 10 – Design Sequence

Digit 1 1 – Tube Material

Digit 12 – Fin Material

Digit 13 — Voltage

Digit 14 — Motor Type

Digit 15 — Motor Mount/Fan Guar d

Digit 16 — Special Coatings

Table SP-1 – Max. Mounting Heights and Distance of Throw for Model S Units

(Based on 2 Lbs. Steam Pressure 60 F Entering Air)

Unit V elocity CFM (F) Height Diffuser Maximum Throw

18-S 162 280 117 8 12 15

20-S2 186 318 118 8 15 18

38-S 319 544 126 9 18 22
42-S 347 590 125 9 20 25
60-S 343 815 129 9 22 27
70-S 454 1 1 00 1 17 10 28 35

90-S 382 1214 127 1 1 28 35
100-S 47 6 1535 118 12 28 35
126-S 41 1 1760 126 13 32 40
168-6 452 2380 127 14 40 50
186-S 528 2808 121 14 45 56
230-S 431 3300 124 15 40 50
260-S 529 4100 118 15 50 62
320-S 442 4480 127 15 50 62
354-S 550 5660 118 15 60 75
400-S 583 6017 122 15 65 80
19-S2 220 390 106 8 18 22

31-S 359 635 104 8 20 25

45-S 363 897 107 9 25 31

53-S 439 1090 105 10 28 35

69-S 407 1337 108 12 30 37

77 -S 458 1510 107 13 32 40

91-S 394 1740 108 14 32 40
127-S 448 2440 108 15 40 50
137-S 495 2700 107 15 45 56
181-S 430 3392 109 15 42 52
207-S 514 4059 107 15 48 60
243-S 439 4607 108 15 55 68
273-S 536 5644 105 15 60 75

Outlet Temp. Mounting Without Set for

Final With Louver Fin

Maximum Throw

Digit 17 — Diffuser

Digit 18 — Manual Starter

Digit 19 — Speed Controller (1 15/60/1
standard motors)

Digit 20 — Thermostats

Digit 21 — Subbase

Digit 22 — Voltage

13UH-PRC001-EN

Selection
Pr ocedure

Model S

Maximum mounting heights for Model
S Unit Heaters are given in Table SP-1.
When equipped with standard Louver
Fin Diffusers the distance of throw may
be increased as much as 25% by “toeing-
in” the ver tical blades.

Distance of throw
decreases in proportion to the amount of
deflection given the airstream to either
side of the heater.

Mounting the unit at or below maximum
mounting height will insure that heated
air reaches the living zone.

Model P

Maximum mounting heights for Model P
Unit Heaters are given in Table SP-1 0,
page 19. These distances are figured
from the floor line to the bottom plate of
the unit heater.
Where ceilings are unusually low, a
nearly horizontal flow of air can be
obtained by equipping these units with
Louver Cone Diffusers. The individually
adjustable blades of the Louver Cone
permit an infinite variety of adjustments
to meet any on-the-job problems. By
setting the blades vertically to straighten
the airstream, as much as 45% increase
in throw can be obtained.

Table SP-2 – Factors for Det er mining Steam Capacity of Model S Horizontal Unit Heaters at Various Pressures and Temperatures

Through 15 1.80 1 .71 1.61 1.53 1.44 1.34 1 .28 1.1 9 1.1 2 1.04 0.97 0.90

Notes:
To determine the Btu per hour capacity of a Model S Horizontal Unit Heater at any steam pressure and entering air temperature multiply rated capacity at 2 psig steam 60 F entering air (Table
SP-3) by factor from above table. Factors in italics: Units should not be operated when entering air is below freezing at steam pressures below 10 psig.

T able Based on 2 PSIG and 60 F Entering Air

Steam T emperature of Entering Air (F)

Pressure PSIG -10 0 10 20 30 40 50 60 70 80 90 100

Blow- 10

Type 20 1.86 1 .77 1.68 1.58 1.50 1.42 1 .33 1.25 1 .17 1.1 0 1.02 0.95

0
2
5

30 1.97 1.87 1.78 1.68 1.60 1.51 1 .43 1 .35 1.27 1.1 9 1.12 1.04
40 2.06 1 .96 1.86 1.77 1.68 1.60 1 .51 1.43 1 .35 1.27 1.19 1.12
50 2.13 2.04 1.94 1 .85 1.76 1.67 1.58 1.50 1 .42 1.34 1.26 1.19
60 2.20 2.09 2.00 1.90 1 .81 1.73 1.64 1 .56 1.47 1.39 1.31 1.24
70 2.26 2.16 2.06 1.96 1 .87 1.78 1.70 1 .61 1.53 1.45 1.37 1.29
75 2.28 2.18 2.09 1 .99 1.90 1.81 1 .72 1 .64 1 .55 1.47 1.40 1.32

1.54 1.45 1.37 1.27 1 .1 9

1.59 1.50 1.41 1.32 1.24

1.64 1.55 1.46 1.37 1.29

1.73 1.64 1.55 1.46 1.38

1.11 1.03 0.96 0.88 0.81 0.74 0.67
1 .16 1.08 1 .00 0.93 0.85 0.78 0.71

1.21 1.13 1 .05 0.97 0.90 0.83 0.76

1.29 1.21 1 .13 1 .06 0.98 0.91 0.84

UH-PRC001-EN14

Selection
Pr ocedure

Table SP-3 – Model S Horizontal Unit Heat er Steam Capacities

2 Lbs. Steam 60 F Entering Air Temp

Size HP RPM P er Hour EDR Lbs Per Hr T emp Air Basis Velocity Weight

18-S 1/50

20-S2 1/50

38-S 1/20

42-S 1/20

60-S 1/20

70-S 1/8

90-S 1/8

100-S 1/8

126-S 1/6 1 100 125,700 525 130 126 1760 411 100
168-8 1/6 1100 172,000 716 178 127 2380 452 145

186-S 1/4 1 1 00 185,200 775 191 121 2808 528 145
230-S 1/4 1 100 229,700 957 237 124 3300 431 190
260-S 1/2 1 100 256,300 1070 265 118 4100 529 195
320-S 1/2 1 1 00 324,000 1350 335 127 4480 442 245
354-8 1/2 1 100 355,500 1480 368 118 5660 550 250
400-S 3/4 11 45 404,073 1684 418 122 6017 583 260

Notes:

1. Constant speed units are rated at capacities shown in regular type: Capacities in italic faced type apply only to
units with multi-speed motors.

2. Capacities based on 2 psi steam and 60 F entering air.

Motor Motor BTU Condensate Final CFM 70 F Outlet Oper.

Standard Units

1050 17,400 72 18 1 17 280 162

950 16,600 69 17 1 18 266 154 40
800 13,900 58 14 1 18 224 130

1050 20,000 84 21 118 318 186

950 19,000 79 20 120 298 173 40
800 15,500 64 17 120 250 145

1550 38,700 162 40 126 544 319

1300 35,900 150 37 130 472 279 40

1100 32,700 136 33 135 399 238

1550 41,600 174 43 125 590 347

1300 38,000 158 39 130 495 294 40

1100 34,700 145 35 136 420 251

1550 60,500 252 64 129 815 343

1300 56,000 234 58 133 706 300 55

1100 51,200 214 52 139 597 256

1550 68,200 285 70 117 1 100 454

1300 64,900 271 67 123 953 397 60

1100 59,700 248 61 128 806 339

1550 87 ,600 366 90 127 1214 382

1300 81,200 340 84 131 1053 334 75

1100 74,200 310 76 137 891 285

1550 96,000 400 99 118 1535 476

1300 91,500 380 94 123 1330 417 85

1100 84,000 350 86 128 1 126 356

15UH-PRC001-EN

Selection
Pr ocedure

Table SP-4 – Model S Horizontal Unit Heat er Steam Capacities con’t

2 Lbs. Steam 60 F Entering Air T emp

Size HP RPM P er Hour EDR Lbs Per Hr Temp Air Basis Velocity Weight

19-S2 1/25

31-S 1/20

45-S 1/20

53-S 1/8

69-S 1/8

77-S 1/8

91-S 1/6 1 100 91,000 380 94 108 1740 394 95

127-S 1/6 1100 125,800 524 130 108 2440 448 135
137-S 1/4 1 100 135,800 567 140 107 2700 495 135
181-S 1/4 1100 180,700 755 187 109 3392 430 180
207-S 1/2 1100 206,900 863 214 107 4059 514 185
243-S 1/2 1100 238,700 995 248 108 4607 439 230
273-S 1/2 1100 272,200 1135 283 105 5644 536 235

Notes:

1. Constant speed units are rated at capacities shown in regular type: Capacities in italic faced type apply only to units with multi-speed motors.

2. Capacities based on 2 psi steam and 60 F entering air.

Motor Motor BTU Condensate Final CFM 70 F Outlet Oper.

Low Final Temp. “Bypass” Units

1050 19,300 80 20 1 06 390 220

950 18,300 77 19 1 08 360 205 40
800 16,300 68 17 11 0 300 173

1550 30,400 127 31 104 635 359

1300 27,800 116 29 109 520 302 40
1100 25,300 106 26 1 1 2 450 257

1550 45,800 191 47 107 897 363

1300 41,300 173 43 1 1 2 740 304 55
1100 37,300 156 39 116 630 259

1550 53,300 223 55 105 1090 439

1300 50,200 209 52 109 940 383 55

1100 46,200 192 48 1 14 795 327
1550 69,400 290 72 108 1337 407

1300 63,400 264 66 112 1125 346 70
1100 57,600 240 60 116 955 295

1550 76,600 320 79 107 1510 458

1300 71,700 299 74 111 1304 300 80
1100 65,800 274 68 1 1 6 1100 341

UH-PRC001-EN16