mum (75) called me today to say her radiators were bumping?

so i pops over there, she says she tracked it down to one upstairs but dont know what one and so turned the upstairs ones off... so by the time ive arrived now theres no bumping.. anyways

ive bled and topped up her pressure in the boiler before now so not 1st time ive done that... but can those in the know have a look at something for me here if you dont mind...

reason being she had a plumber in not so long back to fit a new radiator in the extension and obviously dabbled with the boiler... now i did my usual im a plumber youtube video quick check and im sure he has gone a dn left a switch in the wrong position... i spotted it right away as im sure not 100% but im sure it supposed to be turned other way, and whn i youtubed same boiler with a chap topping up the pressure it has exact same layout pipes and he puts the blue switch ive circled yellow in a different position to how ive found it... can my plumber fellows here take a quick looky and let me know... the 2 pressure pics are 1 before i bled the rads and 1 after... turned off heating in between...26694780_10155727267496999_931950042_n.jpg
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