potterton lynx 2 loss of ch pressure ?

[hotskate]

Hi all...have a problem with my bolier.Just replaced pcb as a fault with dhw relay.
Now have a loss of pressure from the closed circuit central heating.It seems to lose
water out of the pressure relief valve pipe.So i recharge system to about 1bar.This lasts
about 2 days.It then drops down and i have to fill with water again? Could it be that
the pressure relief valve is faulty, after all is 15 years old now, but functions ok other wise?
Any ideas accepted.....ta for reading...><> Robert

 

[Agile]

Watch the pressure if refilled to 1.5 Bar when cold and see what it increases to when the rads are all hot.

If it does not go above about 1.9 Bar then just replacing the PRV will probably work.

Tony