whistling when turning on hot water, old system

[rabu]

Hi guys, just a quick question on what can be causeing a whistling noise that travels though all they system when we have hot water on, doesnt matter wich tap we use or shower, still does it.
Seems to happen when cold water tank level drops to top up the hot cyliner so maby ball valve related? the system is getting on and consitsts of cold tank in roof, hot (primatic) cylinder on ground floor - bungalow, and back boiler for both water & heating. Any help is welcome, thanks.

 

[footprints]

Yes sounds like either the ball valve or a stopcock supplying it, try opening or closing any stopcock to see if the noise changes and perhaps rewasher and check the restrictor is clear on the ball valve or just replace the valve

 

[jeff the gasman]

If it's a part 2 ball valve "google it" it will be the diaphragm washer. If it's a part 1 could be a blocked seating.
Jeff

 

[jeff the gasman]

Footprints beat me to it.

 

[rabu]

thanks guys, will check it out soon as i get chance, its a right pain to get to, to my knowlage its the origional or maby only the second ball valve thats been on since at least 1970 so if its looking tired im guessing its easier to just replace the entire thing? rarther than try to patch up a old one.