Im looking for some advice. Took out an old zero clearance fireplace and air cooled chimney and Im installing a new hearth mounted stove with a through the wall system and up into and existing chase. The new class a chimney will share the chase with my oil boiler (separate pipes obviously). I was all set with the rockvent but i have concerns about the exhaust gas from the boiler withthe 440 rock vent outer stainless they are about 3’ apart. Am i over thinking this or should i be looking for a 304 outer? I think shasta vent ans selkirk are the only ones. I like the rockvent better but looking for advice for someone that knows a little more about this.. i am i. Orange county ny if clate is a concern