Heating zone no heat at radiator

https://www.google.com/search?q=what+can+go+wrong+with+two+zone+heating+systems&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari

I had one zone of a two zone system go wrong. I replaced the zone valve. You're zone valve might have a manual override on it-try and see if it does. If the manual override works, than you need to replace the zone unit. Mine cost about $60.

PS: In my case, the zone valve innards could be replaced without having to reconnect the outside, so torches, etc were unnecessary. It was a very popular model, sold at Home Depot and Lowe's. There is an excellent chance that you can fix that problem without having to call a professional.

Last night I discovered a lever on both valves - "auto or manual" one valve was labeled 1st - assuming this means first floor - I felt the pipe below each valve and above each valve hot on both sides - assume this means water is flowing thru (if so you would think hot water would travel to the 1st floor radiators) - I did move lever on "1st" valve to manual setting - moved over very easy - I assume that by design - waited 30 min or so and felt the 1st floor radiators - still cold. I also located the pump - only one pump - so I assume if 2nd floor is warm pump must be working - pipe below pump was warm but above pump is cold - don't know if that's normal. So the valve control you describe controls the opening and closing of each valve?

I am suspicious of the sloshing sound I hear - occurs also at 2nd floor radiators - assume this is somewhat normal but does it also suggest air in the lines blocking or impeding flow? Some of the 2nd floor rooms are comfortable some of the bedrooms are cooler including both bathrooms.
We get plenty of very hot water at all faucets/showers.

Thanks,

Milty

If I attempt to purge air from the system - I assume I open a low valve on furnace - below water pump? and hook up a hose and stick out door and watch for a stream of water air/bubble free? Or is there another more precise number of steps or should I not mess with purging at all.

Thanks,

Milty

I would personally be afraid to fool around with stuff that can result in unintended consequences, and that includes the electrical, water heater, central heat and ac system. I also do not climb on our roof for any reason.

At this point I am beyond my expertise. Last winter I developed my zone valve issue and, not knowing what it was, consulted a plumbing message board and got really great advice, step-by-step, which really solved the problem. I was going to go back to my Emails to give you a direct link to that forum, but my main Email site has not been operational all day.

However, I checked out this forum:
http://www.doityourself.com/forum/boilers-home-heating-steam-hot-water-systems-128/

It looks pretty good. It was not the forum I used, but like I said I can't find that one right now. This one looks similar. On this forum, the questions are promptly replied to and the people on it seem to be getting the answers they need. I would recommend that one to try, or you can check another.

Good luck. Unless someone comes along on this forum who knows about plumbing or HVAC, I would try that other forum.

Appreciate the link

....Milty