Now whilst I have looked at the past post regarding this, albeit after I went on the call out!, I have thought my issue was a leaking heat exchanger but i'd appreciate a bit of verification to this from those more experienced than myself - having only qualified a few months back.
It's a worcester 24i junior, about 4/5 years old - don't think it's ever been serviced I must add.
Customer complained that the system keeps losing pressure, as many of these faults seem to have the same theme. Went out and did the service requested, all ok. The pressure loss goes like this: from cold, fill to 2bar, you can watch the needle drop rapidly to around 1 bar, it then slows down significantly until it hits 0.5 bar and then there is no noticeable drop - that goes to zero over a longer period of time.
If you turn on the hot water, you get a .25bar drop instantly from any pressure point it was at. CH only gives a fraction of a drop on start up.
Once either DHW or CH is running, the pressure doesnt drop - suggesting something is heating up enough to expand to close any leak.
As I read previous answers after I went, I didn't do the check to see if the condense pipe had water running through it constantly. What I did do though was to isolate the CH to prove the pressure drop wasn't in those pipes. All TRV's and full DHW pipework has been checked for leaks to and nothing. The rapid pressure loss though would certainly show itself if it was a leaking joint somewhere as it wouldn't be a trickle.
I think it's worth making the call to Worcester and getting them to verify but wanted a bit of back up that diagnosis has been done correctly and i've not missed something so totally obvious that someone will make me look foolish when they turn up.
Customer is 40 miles away too, so I can't just pop round to check again!
It's a worcester 24i junior, about 4/5 years old - don't think it's ever been serviced I must add.
Customer complained that the system keeps losing pressure, as many of these faults seem to have the same theme. Went out and did the service requested, all ok. The pressure loss goes like this: from cold, fill to 2bar, you can watch the needle drop rapidly to around 1 bar, it then slows down significantly until it hits 0.5 bar and then there is no noticeable drop - that goes to zero over a longer period of time.
If you turn on the hot water, you get a .25bar drop instantly from any pressure point it was at. CH only gives a fraction of a drop on start up.
Once either DHW or CH is running, the pressure doesnt drop - suggesting something is heating up enough to expand to close any leak.
As I read previous answers after I went, I didn't do the check to see if the condense pipe had water running through it constantly. What I did do though was to isolate the CH to prove the pressure drop wasn't in those pipes. All TRV's and full DHW pipework has been checked for leaks to and nothing. The rapid pressure loss though would certainly show itself if it was a leaking joint somewhere as it wouldn't be a trickle.
I think it's worth making the call to Worcester and getting them to verify but wanted a bit of back up that diagnosis has been done correctly and i've not missed something so totally obvious that someone will make me look foolish when they turn up.
Customer is 40 miles away too, so I can't just pop round to check again!
