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maximum horizontal vent length after penetrating outside wall?
Finally getting around to installing the HTP UFT I bought a while back. Due to the unconventional building design and location of the boiler, venting is going to be more of a challenge than the last mod con I did. I know at some point over the last few years I read somewhere the maximum horizontal vent length for a mod con once it penetrates the wall and is outside. I cannot remember and cannot find this information stated anywhere now. i'd prefer to sidewall vent but i have an excessive roof overhang in the only location I can side vent. The HTP manual says I need to be one inch below the soffit for every inch of roof overhang. So the question remains how far is too far? definitely don't want the condensate freezing in the vent.
I'm hoping I don't have to vent out the roof but even that has it's own set of problems due to the building design. it would be hard to get above the roof line without running the venting up the underside of the rafter at least some distance to get closer to the roof ridge before penetrating the roof. I found one link on this site for venting a a Buderus mod con though an unconditioned space. https://www.bosch-climate.us/files/201001220052570.TBG-5_Guidelines_for_venting_through_an_unconditioned_space.pdf
They're saying insulate the venting if ran in an unconditioned space. It's been quite some time since I've done serious research on this, but correct me if I'm wrong. I believe everything I've ever read said to never under any circumstance insulate Polly or PVC. I'm planning to run Polly by the way.
Hopefully I can run exposed horizontally further than I'm thinking and just side vent.