White Rodgers 50A55-438 installation instructions Timing Specifications

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 μa DC*

Maximum current for non-detection: 0.1 μa 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°C)

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)

	50A55-438
PRE-PURGE	0
TRIAL FOR IGNITION	4
PERIOD
IGNITION ACTIVATION	1
PERIOD
RETRIES	2 times
VALVE SEQUENCE	12
PERIOD
INTERPURGE	60
POST-PURGE	5
LOCKOUT TIME	300
DELAY TO HEAT ON	45
DELAY TO HEAT OFF	60/100/
	140/180*
DELAY TO COOL ON	2
DELAY TO COOL OFF	0/80*
MINIMUM IGNITOR	11
WARM-UP
MAXIMUM IGNITOR	21
WARM-UP
INITIAL IGNITOR WARM-	17
UP (1st 64 attempts)
HUMIDIFIER	YES
ELECTRONIC AIR	YES
CLEANER

*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.

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