White Rodgers 50A55-474 User Manual

2

°

°

Input Voltage:  25 VAC 50/60 Hz
Max. Input Current @ 25 VAC:  0.45 amp

Relay Load Ratings:

Valve Relay:  1.5 amp @ 25 VAC 50/60 Hz 0.6 pf
Ignitor Relay:  6.0 amp @ 120 VAC 50/60 Hz

(resistive)

Minimum current to insure flame detection:  1 

µ

a DC*

Maximum current for non-detection: 0.1 

µ

a DC*

Maximum allowable leakage resistance: 100 M ohms

* Measured with a DC microammeter in the flame probe

lead

-40

°

 to 175

°

F (-40

°

 to 80

°

C)

5% to 93% relative humidity (non-condensing)

Surface mount multipoise

Timing Specs:  (@ 60 Hz**)

Flame Establishing Time:

0.8 sec

Flame Failure Response Time:

2.0 sec

** At 50 Hz, all timing specifications should be increased

by 20%.

Gases Approved: Natural, Manufactured, Mixed, Liquified
Petroleum, and LP Gas Air Mixtures are all approved for
use.

(All times are in seconds, unless noted otherwise)

* These times will vary depending on option switch 

position. The control is factory-set at 0 sec. delay 
to cool off and 100 sec. delay to heat off. See 
OPERATION section for further information.

†

 This time will vary depending on the condition of 

the jumper. With the jumper installed, the delay-to-
cool-off is set at 0 seconds. To obtain an 80-
second delay-to-cool-off, clip the jumper wire and 
separate the jumper legs.

PRE-PURGE

TRIAL FOR IGNITION 
PERIOD

IGNITION ACTIVATION 
PERIOD

RETRIES

VALVE SEQUENCE 
PERIOD

INTERPURGE

POST-PURGE

LOCKOUT TIME

DELAY TO HEAT ON

DELAY TO HEAT OFF

DELAY TO COOL ON

DELAY TO COOL OFF

MINIMUM IGNITOR 
WARM-UP

MAXIMUM IGNITOR 
WARM-UP

INITIAL IGNITOR 
WARM-UP (1st 64 
attempts)

HUMIDIFIER

ELECTRONIC AIR 
CLEANER

0

4

1

2 times

12

60

5

300

45

60/100/ 

140/180*

2

0/80*

11

21

17

YES

YES

50A55-474

0

4

1

2 times

12

60

5

300

45

100 

2

0/80

†

11

21

17

NO

NO

50A55-571