My oil heater was replaced 12 years ago. its been working fine all these years. now I need to move the exhaust exit from roof to gable opening. This will lengthen the tube by about 50%. I will do a tune up afterwards. I see no weight on the adjustable damper and i see no hole to check the pressure. So, I suspect that it was never adjusted when the heater was replaced. Also, the old heater exhaust tube was larger diameter, so the new smaller heater exhaust tube (5.5") is fitted to the larger tube (7") right below the damper. That would effect the pressure, I know. So, Im thinking that I should get new exhaust piping to match the tube coming from the heater, right? However, this means a smaller diameter longer exhaust run. Also a new damper too, one that has a weight that i can adjust. comments?

The Dwyer mark II is the cheapest manometer that i can find resolution down to 0.01 and it has great user ratings. Comments?

bryant install paperwork gives no info on exhaust. beckett paper work says 1/4" rise for every 12", might need an exhaust fan to pull the exhaust out, if exhausting to out side of building, it's better to have the combustion air intake going thru the same wall to balance the unit. I dont understand that and it has worked fine all these years with intake in garage, exhaust outside roof.
comments?

pics: (not allowed)

tks,
pa