Marley 542, 548, 547, 558, 552 Instructions Manual

Ceiling Mounted

Fan Forced Heater

SERIES 500

Read Carefully - These instructions are written to help you

prevent difficulties that might arise during installation of
heaters. Studying the instructions first may save you consid­erable time and money later. Observe the following proce­dures and cut your installation time to a minimum.

1. To prevent electrical shock, disconnect all power coming
to heater at main service panel before wiring or servicing.

2. All wiring must be in accordance with the National and
Local Electrical Codes and the heater must be grounded
as a precaution against possible electric shock.

3. Verify the power supply voltage coming to heater match­es the ratings printed on the heater nameplate before
energizing.

4. Do not install the heater closer than 12” (305mm) to any
wall for models 548, 542, 547 and 24” (610mm) to any
wall for models 558, 552 and 557.

5. Do not insert or allow foreign objects to enter any ventila-

tion or exhaust opening as this may cause an electric
shock, fire, or damage to the heater.

6. To prevent a possible fire, do not block air intakes or
exhaust in any manner. Keep combustible materials, such
as crates, drapes, etc., away from heater.

7. A heater has hot and arcing (sparking) parts inside. Do
not use it in areas where gasoline, paint, or flammable
liquids are stored.

8. This heater is not approved for use in corrosive atmos­pheres such as marine, green house, or chemical storage
areas.

9. The heater enclosure must be securely mounted to ceil­ing or framing capable of supporting the heater (45 lbs /

20.4 kg). Failure to do so could allow heater to fall.

10. Do not operate heater without outlet grilles installed.
When installing grilles with louver guides, make sure
guides drop into position so they cannot slide out during
use.

WARNING

SA VE THESE INSTRUCTIONS

Dear Owner,
Congratulations! Thank you for purchasing this new heater manufactured by a division of Marley

Engineered Products. You have made a wise investment selecting the highest quality product in the heat­ing industry. Please carefully read the installation and maintenance directions shown in this manual.
You should enjoy years of efficient heating comfort with this product from Marley Engineered Products...
the industry’s leader in design, manufacturing, quality and service.

... The Employees of
Marley Engineered Products

Installation & Maintenance Instructions

1

Recessed Mount

Surface Mount

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NOTE: Field wiring must be #10 AWG. min. rated 90°C,min.
Wiring Compartment Volume: 252in

3

(4130cm3)

ADJUSTABLE DISCHARGE GRILLES

CUSTOM AIR FLOW PATTERNS

1. The discharge air pattern is determined by the arrange­ment of the discharge grilles.

2. Care must be taken when selecting location of heater.

NOTE: The discharge grill area is rectangular; the discharge
grilles can only be installed parallel to the intake louvers.

UNPACKING INSTRUCTIONS

This heater is shipped in two cartons.

1. One carton contains the Heater Section, consisting of the
fan, heating elements and controls (Models 542, 547,
548, 557 & 558).

2. The other carton contains the Mounting Enclosure.
There are two types of enclosures: a) Recessed
Mounting Enclosure, Type REA and b) Surface Mounting
Enclosure, Type SEA. Either enclosure is acceptable
with any of the Model 500 Series heater sections.

Both a Heater Section and a Mounting Enclosure are
required to complete the installation of this heater.

INSTALLATION OF SURFACE MOUNTED HEATER

1. Determine the desired location of the heater. See warn­ing No. 4 for min. mounting clearances.

2. Remove the Surface Mounting Plate (Figure 1) from the
carton containing the Surface Mounting Enclosure, Type
SEA.

3. Remove one of the knockouts and install a cable or con­duit connector.

4. Install the optional disconnect switch (if required) as
shown in Figure 1.

5. Run the power supply cable through the connector, leav­ing about 8” (203mm) of wire inside the surface mounting
plate. (Power supply cable must be # 10 AWG min. rated
90°C min.)

6. Position the surface mounting plate against the ceiling
and secure with bolts or screws (Figure 2). See Warning
No. 9. Connect the ground wire to the green ground
screw on the surface mounting plate.

7. Remove the heater section from its carton.

8. Install optional controls (if required) into the heater sec­tion in accordance with the Instruction Sheet packaged
with the control.

IMPORTANT

Field Conversion for Lower Wattage Rating

(Figure 12)

To convert the heater to a lower wattage rating, completely remove
one(1) red jumper wire from one heating element for 25% wattage
reduction. Completely remove two (2) red jumper wires for a 50%
wattage reduction. Discard the jumper(s). Be sure the remaining
wires are securely connected.

Conversion for 3Ø Installation

Heater is factory wired for connection to 1Ø only. To convert to 3Ø,
remove and discard blue jumper wire between L1 & L3. (See Fig. 12,
page 5).

Figure 1

Figure 2

WARNING

FAILURE TO INSTALL THE FOUR MOUNTING NUTS
COULD RESUL T IN THE HEA TER FALLING. (SEE FIG. 2)

WARNING

FAILURE TO INSTALL THE FOUR SCREWS, COULD ALLOW
THE SURFACE WRAPPER TO FALL. (SEE FIG. 2)

Discharge Air

Grille Arrangement

Custom Air

Flow Pattern

NARROW AIR PATTERN for high ceiling
applications (11’(3352mm) to 14’(4267mm)),
concentrates the heated air to ensure full pen­etration to the floor level.

8’

(2438mm)

24’(7315mm)

17’(5181mm)

8’(2438mm)

10’(3048mm)

Heater
Discharge
Grilles

7/8”(22,2mm) &
1-1/8”(28.6mm)
Nested Knockout

1/2”(12.7mm)
Knockout

1/2”(12.7mm)
Knockout

Cable or conduit
connector

Optional
Disconnect Switch

Surface Mounting
Plate

7/8”(22,2mm)
Knockout

Surface
Mounting Plate

Screw (2)

Air Pattern
on Floor

Air Pattern on Floor

Air Pattern on Floor

Screws or
Bolts
(Not Supplied)

Grounding
Screw

Surface Mounting
Plate

Power Supply
Cable

Thumb Pin
Hole (2)

Thumb Pin
Hole (2)

Insure that “Thumb Pin” is pulled out
before positioning the surface wrapper on
the heater section. Depress “Thumb Pin”
after surface wrapper is sealed firmly
against the heater section.

Heater Section

Surface Wrapper

Screw (4)

12”(305mm) Min.4kw
24”(609mm) Min. 5kw

12”(305mm) Min.4kw
24”(609mm) Min. 5kw

Stud (4)

Nut (4)

WIDE AIR PATTERN for standard ceiling
applications (8’(2438mm) to 10’(3048mm)),
disperses the air to give a gentle, less pro­nounced pattern while circulating all the air
from floor to ceiling.

ASYMMETRICAL AIR PATTERN directs
heated air in a specific direction, allowing
the heater to be located where space allows
with the heated air delivered to where it is
required.

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