Filter
Top Products
6-14
Technician Troubleshooting Guides (Continued)
On 8SMS and 8BC units, is 13-17VDC
present at pin 10 when lift is in
UP
position
and zero VDC when lift is in
DOWN
position?
TROUBLESHOOTING
THE CONTROLLER
Is 24VAC
present at pin 1?
Is 24VAC present at pin 4 when
off and zero VAC when calling for
heat?
Yes
Yes
Is 24VAC present at pin 6 when
not
filling and is pin 6 grounded
when filling?
Are the fuses in
the component
box OK?
Replace fuse.No
Yes
Yes
Is 24VAC
present on
transformer
secondary?
No No Replace transformer.
On 8SMS and 8BC units, is
13-17VDC present at pin 12?
Yes
Is 2-3VDC
present at pin 13?
Yes
Controller is OK.Yes
Replace controller.No
No
No
No
No