Filter
Top Products
HE420A STEAM POWER HUMIDIFIER
Automation and Control Solutions
Honeywell International Inc. Honeywell Limited-Honeywell Limitée
1985 Douglas Drive North 35 Dynamic Drive
Golden Valley, MN 55422 Scarborough, Ontario M1V 4Z9
customer.honeywell.com
® U.S. Registered Trademark
© 2006 Honeywell International Inc.
69-1108—2 M.S. Rev. 04-06
APPENDIX B
* Before the SCR can be reset, the system must be checked and repaired by a licensed contractor. To reset the SCR,
insert a rigid, small-diameter object (e.g. paperclip) into the smallest hole in the face of the SCR, next to the green
connector block. This, too, should be performed by an HVAC contractor.
Table 4. Safety Control Relay (SCR) Operation and Troubleshooting Guide.
Condition Cause Action Required
SCR LED shows rapid series of red,
green, and yellow lights, followed by
no LED display.
Condition Normal. SCR processor is
powering up and checking internal
operation.
No action required.
Humidifier won't operate. No SCR
LED display.
Problem! SCR circuit is not closing or
humidistat is not calling for humidity.
Check SCR power; check humidistat
operation. If humidity is about 45% or
outdoor temperature is above 50°F,
the humidifier won't operate unless the
humidistat is set to Test mode.
Humidifier operates. SCR LED shows
continuous yellow.
Condition Normal. This is a test phase.
SCR will wait 30 minutes to detect
furnace blower operation. If the
furnace blower is detected, the system
will function properly.
No action required.
Humidifier won't operate. SCR LED
shows continuous red.
Problem! During the 30 minute test
phase, the SCR failed to detect the
furnace blower and turned the
humidifier off.
Turn the humidistat off, then on again,
to reset the system. Although unlikely
to occur, this failure/reset process can
occur twice before further action is
necessary.
Humidifier operates. SCR LED shows
continuous green.
Condition Normal. All systems
(furnace, humidistat, humidifier and
SCR) are operating properly.
No action required.
Humidifier won't operate. SCR LED
shows flashing red.
Problem! The SCR failed to detect the
furnace blower for the third time and,
as a safety precaution, has locked out
the humidifier. This is an indication
that some aspect of the system
(furnace, humidistat, humidifier or
SCR) has malfunctioned.
Contact your HVAC contractor ASAP
to check out and repair the system.*