Combi boiler pressure spike
I've checked our boiler pressure today and it was at 3 Bar! I've bled the radiators and it's back at 1.6bar, however I wanted another opinion as to whether this was a random spike or if I should get an engineer to come check it out.
For context: we have had the filling loop replaced maybe 3 months ago and at the same time the expansion vessel was refilled as it showed 0 psi, it was refilled and it had no leaks. Since then the pressure has been fine, of course it increased a bit when we were away for a week when it was 36 degrees here everyday, but since then it's been the same level about 1.4-1.5 bar and I've been checking it basically everyday. Then today I checked it and it was at 3 bar, it's been hot here again recently but not so hot that it would have doubled in pressure. I've bled the radiators again and i am going to be keeping an eye on it again. Do you think this was a spike, or do you think something has failed and I should get an engineer? Or keep an eye on it first to see if it does it again?
Worth noting the boiler is nearly 10 years old.
Any questions let me know
Thanks you