Is it possible to add a C-wire to a Honeywell R7284 Oil Primary Control (current two-wire system)?

Question

I currently have a two-wire system (R/W) going to my thermostat. The furnace is an oil heat system with a blower to force air. There is currently a Honeywell R7284 Oil Primary Control where the thermostat wires are running to, both labelled at T T.

I tried looking at the manuals for the system but I'm a little out of my depth as I've not had to mess around with an oil system until I purchased this home, but would like to modernize a bit and add a Wifi Learning Thermostat for convenience.

The cable run up to the wall is pretty straightforward and simple, so I'm hoping one of those other terminals is able to act as a C-wire to provide constant power. Some of the other posts mentioned an F F terminal but mine has a 3/2/1 instead.

Thanks in advance.

Answer 1

I found the manual here: https://jacksonsystems.com/wp-content/uploads/2020/04/R7284-Installation-Manual.pdf

Judging from the sample wiring diagrams and the troubleshooting instructions for "Low voltage xx% low"

 terminal 2 is   C
 terminal 3/T is R
 terminal T is   W

It's possible that the installer knew this, but also possible that they just guessed right.

It is not specified how much current is available to drive your smart thermostat load.