Sterling Hydronic Unit HeatersSteam and Hot Water

Horizontal and Vertical

Horizontal Unit– Standard (Header Type)

• Available in steam or hot water

• Casing constructed out of 20 gauge die-formed steel

• Standard with adjustable horizontal louvers

• Totally enclosed fan motor standard

• (19) Sizes 18-360 MBH• Coil connections on top and

bottom of unit• ETLc Certified

Horizontal Standard Coils

• Cast bronze saddles braised to copper header

• Copper tubing• Aluminum fins• Factory tested at 200 PSI• Max working pressure 150

PSI• Max steam temperature 366 ⁰F• Pipe connections have internal

threads for ease of connection

Horizontal Unit - Serpentine

• Hot water only• Casing constructed out of 20

gauge die-formed steel• Standard with adjustable

horizontal louvers• Totally enclosed fan motor

standard• (4) Sizes 8-36 MBH.• Coil connections on side of

unit• OSHA fan guard is standard• ETLc Certified

Horizontal Serpentine Coils

• Coil is serpentine design with 3/8” copper tubing. Tubing connections shall be 3/8” copper tubing, type “M”

• Aluminum fins• Factory tested at 200 PSI• Max working pressure 150

PSI• Pipe connections have internal

threads for ease of connection

Vertical Louvers (Horizontal Units)

• Vertical louvers are available as a field installed accessory

• Allows for the adjustment of airflow for 4-way air control

Vertical – Standard

• Available in steam or hot water

• Casing formed by two square steel plates

• Totally enclosed fan motor standard

• (15) Sizes 41-705 MBH• Coil connections on top and

bottom of unit• ETLc Certified

Vertical Unit Coil

• Copper coil with aluminum fins mechanically bonded to the tubes

• Coils are tested at 375 PSI• Max working steam pressure

of 75 PSI or hot water up to 225 PSI or 325 F⁰

• Threaded steel pipe coil connections

Vertical – Low Output

• Field knock-outs• (15) Sizes 34-620 MBH• Reduced temperature

rise

Louvers (Vertical)

• OSHA Fan Guards

• Louver Cone Diffuser

Motors

• Explosion Proof• Totally Enclosed

Steam Pressure and Water Control

• Steam Pressure Control

• Strap on Hot Water Control

Starter and Speed Control Switch• Manual Starter • 5.0 Amp Speed

Control Switch

Phenolic Coating• V1 – Phenolic Coating (Air Dried)

– The unit is coated with the Heresite VR-514 coating. – It is a special primer-finish combination that is specifically designed

for salt water services.– It is ideal for use in building located on or near the ocean or other

large bodies of salt water.

• V2 – Phenolic Coating (Baked)– The unit is coated with the Libcote-7-9818 coating.– It is specifically designed for use in moist, wet or damp

environments. – It is ideal for use in waste water treatment plants or in spaces with

excessive amounts of steam or humidity in the air.

HS Tstats• U1- Line Voltage

Stat “Off/Auto Switch”

• U2 – Line Voltage Stat “Auto/Off/Fan Switch”

• U3-STD – Line Voltage Stat “Auto/Off/ Fan Switch”

Tstats Continued• U4 – Celsius

Line Voltage Thermostat

• W1 – T6169C Line Voltage Thermostat w/Subbase (Light Duty) – (VS Only)

• U3-EXP -Line Voltage Stat “Heavy Duty, Explosion-proof”

VS Tstats• W2 – T4051A Line

Voltage Thermostat (Heavy Duty)

• W4 – Q651A1009 Stat Subbase Only (Used with T4051A1003 for “Off/Auto Switch”)

Disconnect

• 115/230 Single Phase

• 208/230 Three Phase

• 460/575 Three Phase

HS Room Layout

When selecting unit size and location keep the following items in mind:• How close will the unit be to people

and small items? You don’t want a unit 4 feet from someone’s desk blowing 5,500 CFM at them

• Always direct units toward areas of higher heat loss such as bay doors and truck loading docks

• Fans with higher RPM will be louder than fans with lower RPM

• See unit IOM for additional information