Flu gas condensate

tonelow54

Recently installed 5 in chimney liner that's venting 60,000 btu furnace and 40,000 hot water tank
Condensation is forming inside of liner and dripping into furnace should I insulate flu liner ?

Paul S_3

Did you perform a combustion analysis? What type of furnace? Is the chimney on an outside wall?

Steve Minnich

This question is not intended to insult you but we've all seen some strange installations to say the least so I have to ask. What is the AFUE rating of the furnace?

tonelow54

It's a brand new ducane 80 percent furnace , did not do a combustion analysis due to the age , and chimney is in center of house

Paul S_3

Combustion analysis shouldve been done at start up with gas pressure test.....any more info you can give us will help....is there a chimney cap?go back perform a combustion analysis stack temp could be too low....gas press out of adjustment etc

tonelow54

thanks for the advice will do combustion analysis , and yes there is a chimney cap will update after performed

MikeSpeed6030

Condensation can be caused by replacing an older boiler or forced air furnace with one that is more efficient. Wringing additional heat out of the combustion process reduces the flue temperature. But, if your new unit is 80% efficiency, that doesn't seem to be the likely cause. Can you link us to the manufacturer's specs for your model?

It's possible that the excess air is off - but a combustion analysis would tell.