Honeywell Spark pilot not working.

[hgpcorp]

My furnace did not start this heating season. When turned to
heat mode it is sparking for about 10 to 20 seconds then the
blower turns on. Looking at the parts on the furnace should I
replace the Honeywell S86E or the Honeywell Valve
VR8440-M2099. Do you think the siginal is bad or the valve is
bad? Thanks for the help. Not too cold yet, but I am sure it
will get there.

[HayZee518]

Could be a few things. the transformer that feeds the spark gap isn't strong enough. the pilot gas supply is clogged, the orifice is clogged, once a flame is established, the millivolt generator bulb that feeds the main valve might be open, the pilot sensing cappilary might be open - so the main valve won't open. If there is a flamerod sensor the wires might be bad so the system locks out. Sometimes spiders build a nest right in the gas/air mix chamber blocking off the gas flow.