awake in suffolk

rudiesdad

Recently I installed two zone valves . The zone valves are on the supply side of the boiler .One zone valve i installed on the bull on a diverter tee this feeds the second floor of my house. The other zone valve is installed on the run , this feeds the first floor . The second floor is baseboard and the first floor is radiators . The first floor is 1" pipe and it seems to be working fine. The second floor usually at night ,most of the time makes a rather loud noise almost sounds like vibrating in the wall. The noise is usually followed by a noise that sounds like a handball bouncing lightly , The second floor is 3/4 pipe straight out of the tee. My question is this air in the system , expansion or is the water flow to much ? thanks