Operating instructions

ManualsBrandsWeil-McLain ManualsWater HeaterC-1013

Part number 550-141-887/0800

AHE Series 4 Direct Vent Wall-Mounted Boilers — Boiler Manual

10a Operation — sequence

Figure 17 shows the AHE boiler control module sequence of operation with status light indications. For more

information, refer to “Troubleshooting” section beginning on page 32.

Figure 17 Control module sequence of operation

1. Standby

Waiting for call for heat

2. Call for heat

Circulator on

Blower on

3. Limit circuit

Limit controls closed

Block switch contacts closed

4. Pressure circuit

Pressure switch contacts

closed

Ignitor heating

5. Flame proven

Gas valve open

Ignitor remains on

Boiler producing heat

6. Limit cycle

Limit circuit open

Gas valve closed

7. Flame outage *

Flame out

Boiler recycles

8. Thermostat satisfied

Circulator off

Blower postpurge

* If flame is not proven in 4 seconds, boiler recycles 2 times to retry for ignition before going into lockout. Recycle igniter timing is 30

seconds. Postpurge and prepurge are performed on every cycle. In event of lockout, ignition control will automatically restore sequence

of operation after either:

1 hour waiting period.

Opening and closing of thermostat circuit.

Removal of 120 VAC power for at least 45 seconds.

POWER TSTAT

CIRC

LIMIT

PRESS

SWITCH

FLAME

Call for

heat?

Timing

= "ON" = "OFF"

YES

—

35 sec

6 sec

—

30 sec

Steps

(Following step 8, cycle goes back to step 1.)

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