Hi Paul,

When I bled the system a few days ago it was w/ the 'pro' that
installed the system. We did the whole thing at the boiler -- we closed
the lower zone so we didn't affect it, turned up the water preassure
and opened a faucet attached to zone 2 (which we hooked up temporarily
to a hose going outside). Water and air rushed out the faucet for a few
minutes (you could feel the pipe vibrating between air and water). We
did this until the flow felt totally smooth, meaning that now only
water was going through the loop. We closed the faucet and turned the
water preassure back to normal (and opened up zone 1). The cold pipe
downstairs started to get warm so he declared victory and left.

I will make a few more tests (wiring of the thermostat, look up more
info on the radiators themselves), and then admit defeat and call the
guy back in. I know he really should be the one doing all these things,
but I'm trying to be self sufficient.

People at work also mentioned I bleed the radiators.Is that any
different than bleeding the whole loop in one fell swoop? I guess I
assumed air would be pushed out of all the radiators when we did that.

Thanks a lot! (And everyone else that has responded, I'll take all your
advice)