York D2NA060 User Manual

16

Unitary Products Group

035-18265-001-A-0202

YES

. Turn gas supply

off

. Set thermostat to

SV9501

is powered

(24 VAC nominal)

Igniter warms up

and glows red

Pilot valves opens

Turn gas on.

Pilot burner lights?

Check

. Line voltage power
. Low voltage

transformer

. Main limit

(Auto reset)

. Rollout limit

(Manual reset)

. Auxilary limit

(Manual reset)

. Thermostat
. Wiring
. Air proving switch on

combustion air

blower system

. Vent damper (if used)

is open and end switch

made

Unplug pilot burner cable,
measure voltage at
SV9501 HSI
terminals (24 VAC
nominal, see inset)

Replace igniter/flame rod as-
sembly

Replace SV9501

Measure voltage to SV9501.
Voltage must be at least 19.5
VAC.

Replace
SV9501

Check
transformer
line volt
supply

NO

NO

NO

NO

YES

NO

NO

Main valve opens?

System OK

Replace igniter/flame rod as-
sembly

Replace igniter/flame rod as-
sembly and retain.
Restart troubleshooting se-
quence.
Does main valve open?

Discard old igniter/flame rod
assembly

Replace
SV9501
save old
igniter/
flame rod as-
sembly for
service

YES

YES

NO

NO

YES

YES