In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Flue liner size for new gas water heater ?
Installing new water heater .62 natural gas 40,000 btu 50 gallon in masonry chimney that is 30 feet high, only water heater now. Washington, D.C. Area. The chimney is on the outside. Going to line with 3 or 4 inch pipe which size is better and should one wrap the liner in insulation even if chimney is already clay lined. Corrugated aluminum liner thinking pipe is corigeted that will be derated by 20 percent. I am leaning toward 4 inch. The water heater has 4 and 3 inch outlet. What size should i use and how important is it to insulate the whole run or more important just at top. Thanks