Water slow to heat up

[isititis]

Hello, A Worcester Bosch 28cdi was fitted early 2002 which is serviced contractually every12 months by a CORGI gas fitter. The problem that exists at this time is with the domestic hot water. When the hot water tap is turned on, the water takes a lot longer to heat up at the point of use. It was normal for the amount of water ( about 2 ltrs) to be lost before it got hot. It is now in excess of 3 ltrs.
Thank you in advance of any help as to the cause and how to remedy the problem.

 

[muggles]

It's either a scaled heat exchanger or a faulty diverter valve, I'd be inclined to go for the latter, the diaphragm is probably perforated. The diverter will need to be removed and either replaced completely or have a new diaphragm installed if this is the case. As you have been cursed with an early 2000s Worcester-Bosch, this is going to be a bit of a pain in the ass. I hope you've got good access to your boiler, especially from below as IIRC these are most ""easily"" accessed from below without having to take too many other things out first

 

[bengasman]

How do you know it took 2 litres when it was new?

 

[MrGassafe]

How do you know it took 2 litres when it was new?

What a stupid, poinless question

 

[isititis]

Sorry for the delay in getting back.
muggles. Thank you for your constructive contribution. The boiler was due for it's annual inspection anyway by B.G. who have been out and have found numerous issues that need to be addressed. The diaphragm,as you sugested, has been replaced. It was also found that the heat expansion vessel needed replacing, which was out of my depth and know-how.

bengasman. I know that something like 2 Ltrs of water passed before the it heated up, because I measured it. How else would I know? Besides why would you need to know that?

 

[bengasman]

Very few people would bother measuring the performance of a new boiler and rely on the memory of an estimate, in which case the info would have been very unreliable.