Install Instructions

ManualsBrandsWeil-McLain ManualsBoilersCGA-4 - 73,000 BTU Output Boiler, Spark Ignition - Series 3 (Nat Gas)

1. All wiring must be installed in accordance with:

A. U.S.A. —N.E.C. And any other national, state,

or local code requirements.

B. Canada —C.S.A. C22.1 C.E.C. Part 1 and

any other national, provincial, or local code

requirements.

2. Pilot lead wires are not field replaceable.

Replace pilot assembly if necessary.

3. If any of the original wire as supplied with the

appliance must be replaced, use minimum 105

°C wire or equivalent. Exception —wires to a

rollout TFE must be 200 °C or equivalent.

4. Thermostat anticipator setting (single zone) —

see Table G for anticipator setting, depending

on which gas valve is installed in boiler.

5. For multiple zoning, use either zone valves or

circulators. Refer to the component manufac-

turer's instructions and this manual for applica-

tion and wiring suggestions.

6. Refer to control component instructions

packed with the boiler for application informa-

tion.

7. Wire any additional limit controls (low water

cut-off, additional high limit, etc.) in series with

boiler rollout TFE and spill switch as shown.

Honeywell VR8204

Honeywell VR8304

White-Rodgers 36E

White-Rodgers 36C

*Terminals 2–4 are factory-jumpered on the

White-Rodgers 36C gas valve.

MV/PV

2–4 *

Table G: Gas valve terminals and anticipator settings

Gas valve

"A""B" "C"

Anticipator

amps

0.6

0.8

0.64

0.7

Electrical shock hazard — can

cause severe injuryor death.

Disconnect power before installing

or servicing.

WARNING

Legend for ladder wiring diagram

120 VAC factory wiring

High voltage spark ignition wiring

Low voltage factory wiring

Ground connectors

120 VAC field wiring

Low voltage field wiring

59374a+LWCO

SERVICE

SWITCH

THERMOSTAT

120 VAC

24 VAC

Control Module

LowVoltage Section

CONTROL

MODULE

120 VAC

SECTION

ROLLOUT

TFE

Additional

limits (note 7)

CIRCULATOR

PILOT GAS

VALVE

MAIN GAS

VALVE

TEMPERATURE

LWCO SENSOR

PILOT FLAME

SENSOR

PILOT

IGNITION

ELECTRODE

HIGH

VOLTAGE

HIGH

VOLTAGE

120 VAC

GndNeutralHot

See Table G

"A"

"C"

"B"

Power

Tstat–Circ

Limit

Damper

Flame

Outdoor Temperature

Sensor (if used)

SPILL

SWITCH

DAMPER END SWITCH

(INTERNAL TO DAMPER)

VENT

DAMPER

24 VAC

CALL

FOR HEAT

24 VAC

CONSTANT

LWCO

DHW (if used)

Part Number 550-142-300/0520

CGa Series 3 Gas-Fired Water Boiler — Boiler Manual

Figure 25b Ladder wiring diagram — Spark-ignited pilot system

Operation — spark-ignited pilot system (continued)9a