Gas and Oil Home Heating Furnaces - LINER Qs

Some 12 years ago a liner was installed in the chimeny that serves the oil furnace.It was a precaution, some of the flue's clay blocks were loose.
The 5'' liner was just bent 90 degrees at the battom and conected to a 5x5x5 Y , the Y to a 6x5 reducer to the furnace flue.
In the last two or three yrs rain water has been driping from the liner and Y joint and corrotion is taking place.
Last year the furnace technician said that this type of instalation was not code anymore [Ontario Canada] and that a T joint [or something of that nature] has to be installed [about $ 500 - $600] for the liner was no longer safe[CO inside the house]

1] I checked the top of the chimeny and liner joint is OK no rain going between liner and chimeny flue.

2]Would installing a bigger rain cap help?

3]Can something be done to replace the small section of liner that seems to be corroded?

4]What is the T suppose to do?

Thanks for help :thinker:

I think I'm in need of a liner and would be intersted in the answers to these questions. So bump bump

deacon

not sure what code is up there for your application, but here are a few ideas

first, the furnace vent is a 6, reduced to 5? that is a big problem, NEVER downsize the flue

the T may be for added draw, possibly needs a barometric damper. that is what i usually see on the "open" side of the tee

is the liner itself damaged or just the tee?

sounds like the problem is being caused by condensation inside the flue (especially if it is undersized) and a new cap will not help

just my dos centavos!

Gracias amigo for help :) :)