Chromalox PF490-5 Model Number Description, Operation, Maintenance and Repair

MODEL NUMBER DESCRIPTION

CXH-A

10

4

3

30

40

1

1

EP

Explosion Proof

Heater Voltage

30 = 24V Controls

1

= Ethylene Group C & D, E, F, G T3B

2 = 240V

6 = 575V

32 = 120V Controls

2

= Propylene Group C & D, E, F, G T3B

0

= No Options

3 = 380V

8 = 208V

3

= Ethylene Group C, D, F, G T3B

1 = 15 or 30 Amp Disconn. Switch

4 = 480V

9 = 600V

4

= Propylene Group C, D, F, G T3B

2 = 60 Amp Disconn. Switch

5 = 415V

3

= Pilot Light

Heating Element Rating

Phase

00 = No Thermostat

4

= Pilot Light and 30 Amp

Disconn. Switch

03

= 3.0 kW

18 = 18.0 kW

1 = 1 Phase

40 = Thermostat

5

= Pilot Light and 60 Amp

05

= 5.0 kW

20 = 20.0 kW

3 = 3 Phase

Disconn. Switch

07

= 7.5 kW

25 = 25.0 kW

6

= Summer Fan Switch

10

= 10.0 kW

30 = 30.0 kW

7

= Summer Fan Switch, Pilot Light

15

= 15.0 kW

35 = 35.0 kW

8

= Disconn. Switch with Summer

Electric Blower Unit Heater for Hazardous Locations

Fan Switch

9

= Disconn. Switch, Pilot Light

with Summer Fan Switch

OPERATION

EXPLOSION HAZARD. Heater should not be operated in ambient temperature higher than 40˚C (104˚F) or in atmospheres corrosive to the heater itself.

1.The CXH-A unit heaters use a sealed water-glycol filled heat exchanger. The electric immersion elements transfer heat energy directly to the fluid generating a fluid/vapor mixture which releas- es its heat energy to the finned radiator as it rises and recondenses back to the bottom reservoir to be reheated. This cycle will con- tinue as long as fan forced air is available on the finned structure to remove the heat to the airstream.

2.The finned structure of the heat exchanger must be kept clean and free of accumulated dust and dirt. The cabinet front panel is easily removed providing access to the heater core for periodic cleaning.

3.Unit should not be operated with louvers fully closed. Mechanical stops are incorporated into the design of the cabinet to limit the degree of closure. Do not force the louvers beyond these stops.

4.If specified, units are supplied with a built in alarm pilot lamp which will energize if the manual reset control has a been activat- ed. During unit startup, the lamp will flash on momentarily to ver- ify its operation.

MAINTENANCE AND REPAIR

Maintenance and repair must be performed by qualified personnel only.

EXPLOSION/ELECTRIC SHOCK HAZARD. Disconnect all power before opening enclosure covers or servic- ing heater. Failure to comply could result in personal injury or property damage.

1.Periodically inspect all electrical connections and terminals to avoid electrical wiring difficulties. Inspect all wiring for frayed or worn insulation.

2.Periodically and before each heating season, clean the finned heat exchanger and fan inlet with compresses air, vacuum, or water jet. Be sure all electrical covers are tightly closed.

3.If heat output seems to be low, check amperage draw on each ele- ment. Compare measured values to the correct currents as listed on the unit nameplate.

4.The thermally protected fan motor is permanently lubricated and sealed. No field servicing is required or should be attempted. Replace only with a factory supplied identical motor. Failure to do so will void the factory warranty and may expose the user to risk of ignition of hazardous atmospheres.

5.Check fan blade to be sure that set screws are tight and there are no cracks or looseness in the blades. Use factory supplied replace- ment blade only.

6.Check for any sign of leaking from the heat exchanger. Too little fluid will cause the manual high limit to trip.

7.The sealed heat exchanger contains a glycol/water solution of propylene glycol. Ethylene glycol is supplied for arctic duty con- ditions only. Avoid contact with skin and eyes. If ingestion should occur, seek medical attention immediately. In case of eyes or skin contact, wash affected areas with large amounts of water. The

MSDS (Material Safety Data Sheet) for these materials is available upon request.

I. REPLACING THE HEAT EXCHANGER

BURN HAZARD. Be sure heat exchanger and fluid has been allowed to cool to 110˚F before proceeding.

1.Detach the cabinet front by removing screws from all sides of unit and pulling cover forward off cabinet shell. Detach bottom panel by removing two screws on each side and two screws in the rear. Remove the electrical control enclosure lid. Disconnect the heater and high limit wires from the electrical control enclosure. Loosen electrical conduit union located between the heater housing and the electrical control enclosure. Support the lower end of the heat exchanger and loosen the three hex head bolts which hold it to the sheet metal. Lower the heat exchanger away from the sheet metal. Reverse the above procedure when installing a new heat exchanger.

II. RESETTING MANUAL RESET LIMIT CONTROL

EXPLOSION HAZARD. Be sure that all enclosure cov- ers are replaced and tightly closed before re-energiz- ing unit after servicing electrical components.

High limit controls must never be bypassed in control circuit.

The factory must perform the replacement of the immersion heater or overtemperature cutout. The heat exchanger seal must not be broken. Consult fac- tory for service.

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