IT is 0 degrees on this fine, sunny Chicago winter morning. The thermostat
is set for 72 and the house is sitting at 65. The house, built in 1967, is
heated with hot water radiant baseboard. Every inch of exterior wall that
can have a radiator, has a radiator. I have blown out the accumulated
dust/dog hairs of 30 years from the radiators so the air is once more
circulating freely. The boiler is busily cycling on and off maintaining a
water temperature of 180 degree. I conclude from that, that the problem is
at the radiator end. The boiler guy was out in the fall and replaced the
expansion tank and air bleeders and bled the system and pronounced it fit

1) WHat is the correct way to fix this?
2) Temporarily, can raising the water temperature to 190 give some relief?
How high can I go?

Note: there are 4 zones to the system but only 1 thermostat. THe house is
equally cool in all zones. I would suspect the wall to wall carpeting
(reducing the air flow thru the radiator) but the one room without the
carpeting is just as cold as everywhere else.