high efficiency with multiple problems long flue

jdfinch

i have a high efficiency that was installed. constantly goes through pressure switches. and does kick on till there is a 20 degree differential. flue comes out end 2" for 12in 90's 12in then adapts up to 4 inches. travels 30 feet 90's travels 15 feet 90's travels 5 ft 90's up and out of the building. i did add a saddle on the 4" about a foot from the transition. it has 1"1/2 pipe down about 16 inches to a trap and empties into a bucket. just trying to stop the condensate from flooding the furnace and taking out the pressure switch. i need advice short of calling a company and having it replaced.

pecmsg

The IOM will have specific ways of running that vent and how to drain.

Ironman

Unless that’s a 400k btu appliance, a 4” pipe is too large and will cause excessive condensation and venting issues.

What size boiler do you have?

How about posting some pics of the boiler and venting?

hot_rod

The installation manual should have the venting sizing table. Lengths, fitting equivalents etc.