I sometimes read these threads and do wonder if im doing the right thing by planning on swapping out my 30yo boiler for a condensing combi. 
When I bought my flat, it was my first experience of a combi boiler. I really do like way it works, hot water on demand, no need to turn on water heater or spark it up 30 mins before you want water. Or having it on a timer, then getting up earlier one day and getting no water, its just always there.
Keep a close eye on the pressure over the coming weeks, in case there is a small, as yet undetected, leak, or if the expansion chamber is fubar... ...and resolve any issues before it becomes a bigger problem. Esp if it means Mrs Tunnie has a cold shower - I can imagine her suffering a sense of humour failure under such conditions in this weather 
Yup, going to keep a close eye on it

Got some points though for fixing it

I was quoted similar call out prices as yourself tunnie
They were insane, strongly considering a course!
Tunnie you say your on the 5th floor. Where does your pressure relief valve vent to? Does it go straight through the wall? Can you see it out of a window? If you can, keep an eye on it to see if it's dripping...
Might be that the spring has got weak in the pressure relief valve... 
Yes I can see it out of the window, will keep an eye on it, did'nt think of that

Sounds familiar. Any popping or banging from the boiler, any bubbling in the pipes?
Not really, its fairly silent when its running
