monoflo t noise

Paul Lang

I just installed a Myson kickspace heater with a B&G monoflo t at the return side of the water pipe. The heater heats up great but there is a louder than usual noise from the monoflo tee (I think) when hot water flows in the pipe. The noise is almost like a coffee maker making coffee (rattling or dripping noise). Is this normal? What could be wrong to generate such noise? How can I reduce the noise? Thanks!