Qmark Open Coil Electric Duct Heaters User Manual

Models FC, SC, FT, ST, RFC and RFT

Open Coil and Finned Tube Duct Heaters

Open Coil Duct Heater Open Coil Duct Heater for round duct Finned Tube Duct Heater

Installation, Operation & Maintenance Instructions

IMPORTANT INSTRUCTIONS

WARNING

WHEN USING ELECTRIC APPLIANCES, BASIC PRECAU­TIONS SHOULD ALWAYS BE FOLLOWED TO REDUCE THE
RISK OF FIRE, ELECTRIC SHOCK, AND INJURY TO PER­SONS, INCLUDING THE FOLLOWING:

1. Do not operate without sufficient air flow. Insufficient airflow
could result in overheating and subsequent damage may
result.

2. DISCONNECT ALL POWER SOURCES before doing any
work on the heater installation.

SAVE THESE INSTRUCTIONS

!

3 Do not connect aluminum supply wires to a standard duct

heater. Order special line terminals that are suitable for
aluminum conductors and are properly sized for the larger
wire gauge they require.

4 Do not install standard heater outdoors. If heater will be

subect to weather, specify raintight construction.

5 Do not bundle, tie or wrap power wiring. This may cause

overheating and eventual breakdown of insulation.

PPD 41026 04/14 5200-11205-000 (ISS 1.0)

INSTALLATION
INSTRUCTIONS

Unpacking the Heater

1. Remove the shipping covers just before installation.

2. Inspect the heater carefully and report any damage to the
manufacturer.

DO NOT INSTALL A DAMAGED HEATER.

Important Notes

1. Do not install a duct heater in a vertical duct directly above
a ceiling diffuser or an opening in the ceiling.

2. Do not install standard heaters outdoors. Order a heater
with weatherproof control box instead.

3. Do not install spray humidifiers upstream of duct. Install it
downstream instead.

4. Do not cover the control box with thermal insulating
materials.

5. Use special air intake louvers of weatherproof construction
for preheat duct heaters to avoid intake of water or snow
particles.

6. Make sure that motorized damper blades are not blocked
with snow or dirt. Inspect the dampers regularly to ensure a
suitable airflow.

Heater Position

1. The axis of the duct must always be perpendicular to the face
of the heater.

2. All heaters are made non-sensitive to air flow direction without
impairing safety. The same heater could be installed in a hori­zontal or vertical duct.

Duct

Heater

Figure 2: Installation of Slip-in Type SC or ST

Duct

Heater

Figure 3: Installation of Flanged Type FC or FT

Air Flow

Heater

Air

Flow

Heater

Figure 1: Mounting Position

Model SC or ST (Slip-in type, See Figure 2)

3. Cut an opening in the side of the duct.

4. Slip the heater into the duct until the hole is completely
covered by flanges around the heater.

5. Fasten the heater to the duct with sheet metal screws and seal
openings with a suitable sealing compound.

6. If the heater is heavy, use additional hangers to support the
heater.

Model FC or FT (Flanged Type, See Figure 3)

7. Flange both ends of the duct outwards on three sides to match
the heater’s flanges.

Dim. “W”

Heater

Obstruction

Dim. “W”

Heater

Obstruction

Figure 4: Minimum Distance for Safety and Service

2

Type SC or ST

Dim. “W” + 10”

Type FC or FT

24”