He said Furnace leaks well furnaces heat air boilers heat water in a
basicly closed loop. He said Auto Fill valve , only Boilers have Auto
Fill Valves not Furnaces. He has a boiler and separate water heater both
separate and non interfering. The only way a boiler will leak is the
plumber accidently bypassed the auto fill pressurising the system to
line pressure or the Auto Fill vale is defective. Either way he must
note the pressure gauge level and turn off the feed and drain it now.
Also He induced new Oxygen into the immediate boiler this must be cooked
off now or the life will be shortened as it will rust over the summer.
This should be done by mnfg . instructions to run time. Its summer , but
it is necessary now.
Expansion tank? He is talking Boiler, it has one already. If his water
pressure is high enough its New Boiler time.
Check feeds first If it was manualy done your Hack owes you possibly a
Dont let that Auto Fill valve go out of your possesion, Mark it and
verify it in writing to any repair man if in fact it tests good, your
hack screwed your system , maybe permanently