Skip to main content

Ready to hire?

Post your job in minutes, browse real reviews and choose who to speak to.Post a job

Need some tips or advice?

Ask a question
Plumbing

I need to turn the heating on to get hot water.....which is clearly not right!

Anonymous user 16/03/2024 - 2.50 PM

Hi, I have a Baxi 105 HE Combi boiler situated in the loft (it was bought brand new and installed Jan 2011). The heating works fine, however I have to have the heating on in order to get hot water. If I run the hot taps fast for a minute or so eventually I get hot water but when I reduce the water flow the temperature gradually reduces until it goes cold again. The shower will not get hot though regardless of running it, I must have the heating on to get hot water through the shower (its a mixer shower). Similarly to the taps, if I run the hot tap until it runs hot, turn the tap off and then use the shower I'll get a minute or so of hot water trough the shower before it goes cold again. I've had someone in a number of times, they have so replaced the diverter valve and also descaled plate heat exchanger. Any help would be very much appreciated!

Are you a tradesperson and able to answer this question?

Log in

4 Answers

AJM heating

Rating: 5 out of 5
Hook
Would like to check flow sensor to see if it’s lighting on demand firstly. As you may not be generating enough flow to fire the boiler. Sounds like they replaced the diverter cartridge not the whole valve set. There is also a HW Temp sensor that measures the temp and modulates the boiler down once at temp. The plate needs to be replaced descale rarely gets a long term solution and is false economy.
Answered9 May 2023
4

Corey Davies Plumbing & Heating

No reviews yet

Swansea
Is it over heating when the water is being run? Does the flame symbol cut out when the tap is running? Descaling a plate exchanger never works to be honest I always would fit new. I wouldn’t go spending to much on the boiler either in all honesty I’d be thinking about replacing the whole boiler for efficiency purposes now.
Answered10 May 2023
0

Cochrane Property Maintenance

Rating: 5 out of 5
Chepstow
Sounds like the diverted valve has failed / broken inside the combi boiler . I’d recommend a replacement diverter valve For a baxi 105he You’ll need a gas safe registered installer to do it :)
Answered10 May 2023
0

R N Hill plumbing

Rating: 4.9 out of 5
Accrington
It could possibly be the micro switch.If I remember rightly on this boiler it's just a straight forward brass diverter valve with a diaphragm.So when you turn a hot tap on it pushes the diaphragm towards the micro switch which then fires the boiler up.Thats if they have changed the diverter valve and diaphragm.I think it's the same set up as the 105E .
Answered8 June 2023
0