11.After 15 to 70 sec, the gas valve permits gas to flow to the main burners where it is ignited. Hot flames begin to warm the furnace’s heat exchanger. After a time delay of approximately 45 sec, the furnace blower is switched on.
F |
OF |
|
| 12 |
|
| M | 1 |
|
O | P | 3 |
|
F |
|
| |
|
|
| |
F | C | 2 | OR |
| |||
|
| ||
| ON |
| |
|
|
| |
|
| 13 |
|
OFF | ON |
16 |
17
18
ON
OP
E
N
|
| 14 |
|
| M | 1 |
|
O | P | 3 |
|
F |
|
| |
|
|
| |
F | C | 2 | OR |
| |||
| ON |
| |
|
|
| |
|
| 15 |
|
OFF | ON |
5
19
NOTE: If the main burners fail to ignite, the furnace control system will go through 3 more ignition cycles. If burners still fail to ignite, the system will lockout. (Under some circum- stances the furnace may reset from lockout and attempt to ignite if a call for heat still exists.) If lockout occurs or the blower does not come on, refer
