The module is rated for combination gas controls
with pilot valves up to one ampere and main valves
of up to two amperes. The S8610U has ignition and
flame sensing circuitry that accommodates either a
combination igniter-sensor (single-rod) or separate
igniter and sensor (dual-rod). A vent damper plug is
standard. Although there is no formal prepurge cycle,
the module does have a short initial delay before the
ignition sequence and can be used to replace systems
with a four-second or less prepurge.
One feature that allows the S8610U to serve as a
universal replacement module is its unique continuous
retry sequence, which provides safe control in applications
using either natural or liquid propane (LP) gas. On
a call for heat, the S8610U begins a 90-second (nominal)
trial for ignition. If the pilot flame is not sensed within
this period, the S8610U de-energizes the pilot valve and
shuts off the spark. The S8610U waits for five minutes
(nominal) to allow venting of accumulated gas, and then
the trial for pilot ignition begins again.
ICM/July/August 2019 19