Warning – Qmark IUH - Industrial Unit Heater User Manual

Page 3

Thermal Safety Cutout: Each unit heater is equipped with

one or more thermal safety cutouts which will automatically

shut off the heater in the event of overheating, and will acti-

vate the heater when the operating temperature returns to

normal. If the thermal safety cutout cycles due to overheat-

ing, the cause should be determined before further operation.

LOCATION OF HEATERS

Refer to min. and max. mounting heights and clearances in

Specifications table. Mounting heaters too high will require

setting the louvers sharply downward to direct warm air

toward the floor, thereby decreasing the distance of the air

throw. Heaters should be arranged so that the discharge air

stream will not be restricted by columns, machinery, etc.

Heaters should be installed out of the reach of persons.

Heaters may be rotated and louvers adjusted to obtain the

desired direction and distance of warm air discharge.

Where a remote thermostat is used, it should be located on

an inside wall or post, out of the direct rays of the sun and

internal heating sources, and away from cold drafts.

The number and capacity of heaters required should be

determined by the heat loss of the structure. Small areas can

be heated by one unit heater. Larger areas require multiple

units. Where multiple units are required, the air discharge of

each heater should support the air flow of the others to pro-

vide perimeter rotational circulation of warm air. (See Figure

1).

MOUNTING THE HEATER

10kw thru 30kw: A 1/2”-13NC threaded mounting hole is

provided in the top of the heater for securing the heater to an

optional mounting bracket, or other mounting structure hav-

ing a minimum of 10” (254mm) clearance from the ceiling.

Combination wall/ceiling, wall, and ceiling mounting kits are

available from your electrical distributor. They are designed

to mount the heaters on wall or ceiling, provide adequate sup-

port, insure proper clearance from walls, and permit rotation

of the heater. Installation instructions are included in the kits.

If one of the mounting kits is not used, the installer must pro-

vide suitable means of mounting heaters securely, allowing

adequate clearance from adjacent walls and ceiling as indi-

cated in the specifications chart.
5kw & 7.5 kw: In addition to the 1/2”-13 NC threaded mount-

ing hole, the 5 kw & 7.5 kw heaters are supplied with a hanger

bracket. The bracket may now be mounted for horizontal air

discharge in the double keyhole slot which will space the top

of the heater 1-7/8 inch (47 cm) from the ceiling (Figure 2), or

it can be attached in the single keyhole slot for horizontal or

vertical mounting.

INTERNAL WIRING

1. Heaters drawing 48 amps or more have internal sub-

divided branch circuit fusing.

NOTE: A properly fused disconnect switch or suitable

circuit breakers must be installed between the heater

connections and power supply.

2. All wiring connections are made inside the control box at

the bottom of the heater. To open control box, loosen

screws holden the hinged cover at front (if cover is slotted)

or remove screw(s) (if cover is unslotted) and open cover

(Figure 3).

3. Knockouts and terminal blocks are provided for power

supply connection, and connections for heater controls.

EXTERNAL WIRING

1. Supply wire size should be selected in accordance with

the electrical rating shown on the heater data plate

and/or wiring diagram (located on inside of control box

cover), and must be suitable for 75° C.

2. Connect conduit to appropriate knockout on control box

panel. If rigid conduit is used, connect to heater with suf-

ficient length of flexible conduit so heater can be rotated as

desired.

3. Connect supply leads to the heater terminals and connect

any required jumpers as shown on the wiring diagram.

4. After all connection are completed, close and secure

control box cover.

Figure 2

Figure 3

Before proceeding further with the installation of the heater,
turn off the power to the supply line for the heater at the
main service box.

WARNING

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Figure 1

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