Losing hot water

[thurne]

I have a Worcester 24cdi combi (approx 4 years old). After using the shower (not electric) for around 2-3 minutes the water gradually gets colder, then takes a minute or so for the water to heat back up again.
The water pressure is 1.5 bar (approx). The heating is on and the water temperature is set at maximum.
I would like to know whether this problem is something that I can rectify myself or whether I need to get a plumber in.
Thanks.

 

[Agile]

Your boiler can only supply about 8 litres of hot water per minute. You should measure the flow rate to see if you are expecting too much. Measure at a TAP as you may have a thermostatic shower which is adding cold water to the boiler output.

If you are taking no more than 8 li/min then there may well be something wrong with the boiler but a boiler engineer would be better than a plumber.

Call a plumber if the shower is faulty.

Tony

 

[thurne]

Your boiler can only supply about 8 litres of hot water per minute. You should measure the flow rate to see if you are expecting too much. Measure at a TAP as you may have a thermostatic shower which is adding cold water to the boiler output.

If you are taking no more than 8 li/min then there may well be something wrong with the boiler but a boiler engineer would be better than a plumber.

Call a plumber if the shower is faulty.

Tony

Thanks Tony,

The shower is a standard type (not thermostatic - water running from tap pipes). The problem of losing the hot water has only recently happened - I could quite easily have a shower for over 10 minutes without loss in temperature.

 

[Agile]

It may well be a boiler fault then but I would still be happier if you had measured the flow rate as the problem happens. There is always a possibility that the flow rate is increasing beyond what the boiler can handle.

You have to be aware that when professionally repairing boilers we have to test everything step by step to enable us to find the fault without being sidetracked.

You said the fault was when using your shower !!! The boiler does not know where its providing water to. Hopefully you meant to say that the problem is at a tap, shower or washing machine or anywhere the hot water goes !!!

Unless you are clever with electronics I would expect you may need to call a boiler engneer who may find the DHW flow switch or the APS or the NTC sensor has failed.

Tony Glazier