What Determines How Quickly Cold Water Turns Hot When Running The Tap?

[ladybirder]

It takes 3 or 4 large bowls full since I had a new Bosch gas boiler installed. With my old boiler it was about 2.5 to 3. Nobody else I have asked in my block of flats has to wait as long. Is it controlled by a setting on the boiler?
Thanks.

[dannyk13]

Is the new boiler in the same place as the old or is it further away from the taps.

[dannyk13]

My boiler has a control on the front that controls the temperature of the heating.

[davebro]

First it has to heat up the heat exchanger then the heated water has to flow to the tap(s). My bathroom basin is about 20 feet from the boiler & it does take a little while for the hot water to come.

[davebro]

Ideally (rich folks) have a circulation system with super-insulated pipes so that you get hot water as soon as you turn the tap!

[Etch]

Perhaps the pre-heat function, if available on your boiler, has not been turned on:
https://idealheating.com/installers/support/faqs/boiler-controls/what-does-pre-heat-mean

Can you give us the model number of your boiler?

[ladybirder]

Same Danny thanks.
So has every boiler hasn't it? The water doesn't even start to get warm until after 3-4 large bowls.
My boiler is in exactly the same position as other flats Dave and their water heats up more quickly.

[dannyk13]

Suggets you give etch the model number and he may be able to help.

[dannyk13]

^suggest^

[davebro]

I did have a problem a while back where I had to put the water on full flow to get it to heat up. There was a tear in the diverter valve bellows stopping the valve from triggering the burner at low flow rates. Not sure if more modern boilers still use the same system.

[davebro]

how big is a "large bowl" - is an increase of 1/2 bowl a lot?

[davebro]

Just checked mine with a measuring jug (it's a slow day!). At a good flow it takes 3.5 litres before the water runs hot.

[Etch]

If it's one of the Worcester range of boilers (and possibly others) then the pre-heat function is controlled by the ECO button, according to this article:
https://www.worcester-bosch.co.uk/support/troubleshooting/faqs/all-faqs/why-might-i-want-to-programme-hot-water-times-with-my-combi-boiler

[ladybirder]

Sorry been looking to find the model. It is GREENSTAR 25i ErP NG COMBI.

[Etch]

Thanks ladybirder. From the manual for your boiler:
"• Eco mode is an energy saving feature which disables the Preheat
function. Eco is enabled by default, during the initial appliance start
up and Eco is displayed.
• Preheat mode, the hot water heat exchanger is kept pre-heated to
reduce the time taken to deliver hot water at the tap.
In the Preheat mode, if there has been no demand for hot water for 24
hours the appliance will save energy by suspending Preheat until there is
a demand for hot water. At this time Preheat mode is re-activated.
▶ Press the eco button (approximately 1 second) to manually switch
between eco [1] and preheat [2] modes.
Depending on which mode the appliance is in, pressing the eco
button (approximately 1 second) switches from one mode to the
other."
So, is your boiler in "Eco mode" at the moment?

[ladybirder]

Ah Etch that is a useful link, thank you. I will check later to see if the Eco button is on or off. Then I'll have to decide what to do as I absolutely hate wasting water. I have a vision of children dying for want of a sip.
So it is the boiler setting then. Good.
Cheers everyone.

[New Judge]

When you make that decision you are really deciding whether you want to waste water or gas. If you use your water infrequently, then keeping the pre-heat function on means you are keeping a small amount of water that you don't use constantly heated. As it cools the boiler will kick in and heat it up again. This goes on 24/7.

I have the facility on my boiler and I keep it switched off (especially in the summer when it takes less time to get to temperature). If I remember I switch it on before a few minutes before I need hot water but it really doesn't matter. I once accidentally left it on when I went away for a fortnight and it cost me a pretty penny to keep a hot water supply readily available.

When you make your decision bear in mind that water is considerably cheaper than gas and the water that you waste is unlikely to find its way to anybody needing it. As for the water companies bleating there is not enough of it about - there is, and plenty. It's their job to capture it and store it until required, for which they are paid handsomely.

[bednobs]

if you really are worried about wasting water, have a bowl handy and keep the water for using elsehwere

[ladybirder]

Thanks NJ, that's what I'm thinking about and I'm coming to your way of doing it. Might be cheaper to boil a kettle of water for washing dishes.
Bednobs thanks but have one bucket only and quite honestly I don't know what I would do with all that cold water.
Just had a brainwave ... Get my water from the Shower, it runs hot almost immediately;-))

[1ozzy]

Bob The Turkey has lots of buckets Ladybirder, maybe he could give you one of his.
Hope you like orange

[bednobs]

Put it down the loo instead of flushing? Water your plants?