How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Andrew Smith Your Own Question
Andrew Smith
Andrew Smith, Engineer
Category: UK Plumbing
Satisfied Customers: 3633
Experience:  Domestic Gas, Commercial Gas, LPG, Unvented Hot Water, Part P Electrical, Commercial Catering
Type Your UK Plumbing Question Here...
Andrew Smith is online now
A new question is answered every 9 seconds

We have Ferroli Modena 102, the issue we have is we changed

Customer Question

Hello we have Ferroli Modena 102, the issue we have is we changed the electric shower to thermomix shower, at first we have hot water but after 5 secs it turns very cold do you know what the problem is?
Submitted: 2 years ago.
Category: UK Plumbing
Expert:  Andrew Smith replied 2 years ago.

It sounds like the water is too hot, so when the shower valve throttles the hot water down to reach the correct temperature it drops below the minimum flow rate to keep the boiler lit.

Try turning the hot water temperature down 25% to make sure there is plenty of hot water flowing

Customer: replied 2 years ago.
This also happens with the kitchen taps. We've notice that when turning hot water on the boiler doesn't respond to say we need hot water. Could it be that the boiler is very old and need replacing? Central heating system is fine
Expert:  Andrew Smith replied 2 years ago.

It will be the divertor valve.

Inside it is a rubber diaphragm that stretches over time, therefore more water flow is needed to fire the boiler when in hot water mode.

You can get the washer swapped for about £100, or the whole valve for abour £220