White Rodgers 50A55-438 User Manual

SPECIFICATIONS

ELECTRICAL RATINGS [@ 77

F (25

C)]:

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)

Flame Current Requirements:

Minimum current to insure flame detection: 1

a DC*

Maximum current for non-detection: 0.1

a DC*

Maximum allowable leakage resistance: 100 M ohms

*Measured with a DC microammeter in the flame probe lead

OPERATING TEMPERATURE RANGE:

-40

to 175

F (-40

to 80

HUMIDITY RANGE:

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

MOUNTING:

Surface mount multipoise

TIMING SPECS: (@ 60 Hz**)

maximum

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, Liquefied

Petroleum, and LP Gas Air Mixtures are all approved for use.

TIMING SPECIFICATIONS

(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.

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

2 times

300

60/100/

140/180*

0/80*

YES

50A55-438