I have a ducane oil fired furnace, During the winter my burner was giving me problems so I replaced it.. Now that its summer I knew I had to mess around with the wiring Because I only tied in R/W from the tstat to the primmary for heat.. Come to find out the Beckett AFG I installed is not matching up to the old wiring.. Looks like I need to install a separate fan center to get the indoor blower to come on.
My question is.. When I install the fan center I can just use the thermostat as the isolation correct? No jumper from RC to RH.. that should isolate the 24 volts forom the primary on the burner with the 24volts from the fan center right? Just looking for a conformation or a correction on this as I do mostly Plumbing.
Thanks in advance!!

Considering the possible age of the unit, the limit control determines when to turn on the fan. When the plenum gets hot enough, the fan turns on and when cool enough it turns off.

This can also be done with blower on/off delays.

When a thermostat is set for conventional heat, the furnace controls the fan through the limit control or the delays.

For Fan Only to work, there needs to be a connection to Rc and G because G is activeated through the cooling source of power.

The honeywell website www.honeywell.com does have wiring diagrams for the fan center.