Accong to the Z Flex liner chart I have in front of me.
6" liner can handle 213,000 BTU's at a 35' chimney height.
By code, if your water heater has a 3" hood, it can't be vented into a chimney that has more then 49 sq inches area.
If your installer read the install instructions(which I doubt), he would know that HE was suppose to verify if the chimney was sized right or not before he installed the boiler.
Draft readings would be nice.
I think you need another contractor.
Screen them on the phone. Let them know them problems your having, so they can bow out gracefully if they don't know how to check everything.
No readings available, go figure.
Appreciate the confirmation on the EZ liner load capacity.
I will start looking for a new HVAC guy. Too bad, I need two new AC units installed as well. Looks like he will lose out on those as well.
Maybe its a good thing that the boiler problem is happening now instead of a year from now.
Yea, I guess thats one way of looking at it.