Ariston Eurocombi HW problem

[mike3671]

Hi
We have just moved into our new house and it has an Ariston Eurocombi(its either an A/23 or A/27 MFFI)

We had a problem with the hot water not staying constantly hot.

I have read through the manuals and checked online and thought I would try the adjusting the flow rate.I have managed to get the HW to stabilise for a nice hot bath but the flow rate is now 6 litres a minute.

I have a few questions

1-I need to get a thermometer to be more precise but am I correct in assuming that where it says 'Flow rate at /\T 35c' means it will raise the water temp of xlitres 35c?

2-If it turns out that the boiler is OK and I am asking it to do too much(my partner has a rare condition and subsequently a nice hot bath is one of the few things that eases the pain)will running it at this reduced flow cause any damage?

3-I have read a few posts regarding sludge in the secondary heat exchanger,is it an easy job to get it out and clean(I am an electrical engineer) so I am confident in stripping it down unless it involves breaking into anything to do with the gas.

4- This is totally unrelated but the CH system has no wall stat, but each radiator has a thermostatic valve.Does the boiler shut down automatically when there is no demand for the rads or continually cycle.Is it worth installing a room stat to save energy?

Thanks

Mike

 

[Agile]

As an electronics engineer I am surprised that you have not realised that the boiler can only run all the time when its on CH as there is not any communication from the system to the boiler. It therefore cycles to maintain the flow at the set temperature and burns gas totally unnecessarily. Thats why the Building Regulations require a room stat to be fitted!

The plate HE is easy to remove if you are capable of mechanical work on water carying components. Cleaning is easy but to do it properly you have to use acids and be competent to work safely with chemicals.

The spec says that it will increase the temperature by 35°C when the flow rate is 9 li/min . As your plate HE is blocked the boiler is unable to transfer the full amount of heat. Its unlikely to do any permanent damage but its better to get it fixed sooner. We charge £106 in the London area including a service and performance check.

Tony Glazier