We recently had our bathrooms remodeled and new faucets installed in each. The bathrooms share a common wall where the plumbing exists. When I turn on the hot water faucet past about midway, a loud, rapid hammering noise is heard in the pipes. I am told this is probably due to air in the line. If so, how do I bleed out the air? If not, what else might be causing it?
Thanks.

I am told this is probably due to air in the line. If so, how do I bleed out the air? If not, what else might be causing it? Let's use a little common sense. If it were air in the line the faucets would be spitting air and water all over the place. So if it's not air then what is it? This sound is what we uased to call "seat chatter" and is caused by something, a loose washer or a small pebble, vibrating against the seat of the faucet. "Chatter" is caused by vibration. When I'm faced with this problem I start the chatter and fell around until I feel the spot where the vibration's the strongest. That's where I began to look. The new faucets would be a dandy place to start. Good luck, Tom

I failed to indicate how loud and severe the banging is - is shakes the faucets to the point where it would seem something is going to break...

Adamsonp... tell us is this happening when you open BOTH faucets.. Or just one?

Tom is dead on with his description... SEAT CHATTER can cause some very violent chattering/banging of pipes... so sounds most likely.. but tell us if this is happening at both faucets.

Thhanks, guys. Only happens with the hot water side, not the cold (in master bath.) I will check to see if it occurs from the guest bath.

If it is ONLY hot side in ONLY the master bath faucet, then it has to be that seat chatter Tom mentioned... would need to shut off water to faucet and then remove the stem assembly and check for loose washer/debris (after removing stem from hot side, PULSE the water shutoff to purge line of any loose debris). Name the faucet and model number and we may have a picture for you to work from...OR

Call the plumber back that installed the faucet.. it is not necessarily anything to do with him. but he can make quick work of this... let us know. Talk later... Mark

I just had my wife run a test from the guest bath - the hot water bangs from there too, and the cold still does not.

OK.. like Tom suggested, when you get home, open the hot faucets and feel around at faucet, under cabinet.. see where vibrates the most.

This could be seat chatter, could be water hammer, could be combination of all these, plus the pipes being hung improperly... hard to say from here... check it out.. let us know... Mark

I had read in another post, that a similar problem was solved by increasing the water flow from the shutoff valves beneath the sink so I gave it a shot. Mine were opened less than a full turn; I openend 'em up and no more noise! If it returns, I will be sure to follow your troubleshooting instructions. Thanks for the help.