Natural gas baseboard heating system "bucking"

[romec]

My existing home has a natural gas baseboard heating system. I recently bled the system and wound up messing with the pressure setting on the pressure-reducing valve that feeds the furnace. I also messed with the pressure in the expansion tank attached to the furnace. Ever since then my system bucks when the furnace kicks on and/or whenever thermostat calls for more heat. The bucking sound sounds like someone is taking a hammer to the pipes for about five seconds. Is there anyone who can explain to me what I can do in order to correct this condition?

Please advise.

Thanks.

[xkvator]

check back this evening & the xperts - MDSHUNK & DUNBAR PLUMBER will give you the answers to your ?

and they might want to know why you messed with the pres. red. valve :confused:
and what is the pressure gauge on furnace reading?
did you shut off the supply water before you bled the expansion tank?

[DUNBAR PLUMBER]

I believe the pressure for those systems is 12 pounds. You will need a gauge to determine what the pressure is. Also, the expansion tank will need to be set to the working pressure of the system to avoid premature wear on the expansion tank.