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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White Rodgers 50A55-438 installation instructions Timing Specifications

50A55-438 specifications

The White Rodgers 50A55-438 is a highly versatile and efficient thermostat widely recognized for its reliability and advanced features. Designed with both functionality and user-friendliness in mind, this device serves as an excellent solution for managing heating and cooling systems in residential and commercial applications.

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In summary, the White Rodgers 50A55-438 stands out as a top choice for those seeking an advanced, efficient, and easy-to-use thermostat. Its compatibility with various HVAC systems, programmable features, energy-saving capabilities, and robust design make it an excellent investment for effective climate control. Whether for residential or commercial use, this thermostat meets the demands of modern temperature regulation with precision and reliability.