chimney liners

Stan_5

I was wondering if someone could help me with a chimney liner question. We are installing a 90% direct vent furnace and pulling a flexible metal liner down an exterior chimney for the water heater. The chimney was relined recently with a cast in place lining system. Does the metal liner need to be installed or does the cast in place lining system take its place.

Tim McElwain

What are the interior dimensions

of the existing chimney? What is the BTU input of the water heater? Is the existing chimney without the liner acceptable to the local inspector?

Stan_5

chimney liners

The existing chimney was 6 3/4 x 6 3/4 inside dimension but because of the cast in place liner its less, maybe at most 5". The water heater is about 40,000 btu's input. I was wondering if the cast in place would insulate the chimney enough so that the water heater could vent into the chimney without a metal liner. I don't know if it would be acceptable to the local inspector or not. I can't seem to find any info on line that addresses this. Perhaps its best to just pull the liner but why do it if it's not necessary. I don't know the height of the chimney, a fellow co-worker asked me about this so I thought I would do some digging for him.

PeterNH

Liner

If it's a "Golden Flue" there should be no problem.

Peter