Chromalox CAS-20CM User Manual

(Supersedes PQ435)

PQ435-1

cas

161-562795-001

JUNE, 1994

4

and

Installation, Operation

RENEWAL PARTS IDENTIFICATION

Type CAS-20CM Electric Steam Boiler

(Standard Trim is 100 PSI — 0-90 PSI Operating Pressure Range)

© 2010 Chromalox, Inc.

Model Electric Capacity BHP Rating Voltage Phase Amperes Drawn Contactor

20 kW 2.0 208 1 96 50A, 4 Pole

16/20 kW 1.6/2.0 208/230 3 45/51 60A, 3 Pole

CAS-20CM

20 kW 2.0 240 1 84 50A, 4 Pole

20 kW 2.0 346 3 34 40A, 3 Pole

20 kW 2.0 380 1 53 60A, 2 Pole

20 kW 2.0 480 3 24 30A, 3 Pole

Note: Control circuit 120V

Boiler Serial No. ______________________________________________ Power Circuit Voltage __________________________

Model No. ___________________________________________________ Control Circuit Voltage__________________________

National Board No. ____________________________________________ Amps ___________Phase __________Cy __________

IMPORTANT – This data file contains the National Board Registration Certificate approving your boiler. It must be kept near the boiler at all

times.

INSTALLATION

WARNING: To avoid electrical shock hazard, boilers

must be suitably grounded to earth.

Note: Chromalox boilers are pre-tested before shipment; no inter­nal piping or wiring is necessary. WARNING: Substitution of
components or modification of wiring without prior consent of
Chromalox voids warranty.

1. Bolt unit securely to level floor or platform.
Note: A minimum distance of 18 inches from wall, other

equipment, etc. must be allowed for removal of the elements.

2. Complete all piping to boiler. Connect water line to tagged fit­ting on the motor and pump assembly if used, or to tagged fit­ting on water control feeder.

3. When any type of feed other than a pump feed is used, the

water supply line pressure must be 10 pounds greater than the
boiler operating pressure to assure proper water level in boiler.
Lack of water can cause heater failure. Keep feed water line
valves open at all times.

4. Connect steam line (with outlet valve) to boiler steam outlet.

5. Open all gauge valves and steam outlet valve; keep drain valve

closed.
Note: The safety valve should be provided with a drain line
sized no less than the outlet size of the valve and routed per
local codes.

6. Floor drain to be provided directly below unit.

WIRING

Type CAS
Electric Steam Boiler

WARNING: Hazard of Electrical Shock. Disconnect
all power before working on boiler. Boilers must be
grounded in accordance with the National
Electrical Code (NEC) standards to avoid shock
hazard.
WARNING: Use 90°C copper conductors only.

1. Select proper wire gauge and type for supply conductors in
accordance with the National Electrical Code and local wiring
codes following wiring diagram supplied (See recommenda­tions for disconnect switches and fusing).
Note: Purchaser should use a safety disconnect employing cir­cuit breakers or fuses between the main power source and the
boiler. This overcurrent protection should be installed in addi­tion to any other supplementary fuses or circuit breakers pro­vided as an integral part of the boiler.

2. If a separate control circuit is used, the control circuit should
be connected to the control terminal block and the circuit pro­tected by overcurrent devices in accordance with the National
Electrical Code.

3. Chromalox boilers are solid state devices. Since boilers are
connected to water lines, these devices are susceptible to volt­age surges and lightning damage. Industrial type lightning pro-

tectors should be installed per manufacturer’s recommenda­tions at your service entrance.

4. Be sure that all electrical connections are sufficiently tight-

ened. Loose connections will cause overheating and damage to
the electrical wiring.

5. Special instructions for customers supplying their own con-

densate or pump system.

A. Check the voltage of the motor before making the wiring

connection. The motor should always match the voltage of
the control circuit. Standard control circuit voltage is 120
volts ± 10 volts.

B. Internal water feed relay is rated at a maximum of

1

/3 H.P.,

120 volts. Motors rated greater than

1

/3 H.P., or other than

120V, single phase, require the use of a suitable motor starter.

6. After all service connections are made, open feed water supply

valve and energize the boiler. The feed water solenoid will
open, fill the boiler to the proper water level and automatical­ly shut off. The feed solenoid will continuously cycle on and
off as the boiler requires water. If, for any reason, the water
drops below the minimum safe operating level, the boiler’s
electrical circuits, except the feed solenoid will be de-ener­gized automatically. Upon refilling to the proper level, the
boiler will automatically restart.

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