Combi Boiler hot water problem

[Danblade]

Hi.

New house and never had a combi boiler before. When I run a bath it comes out hot but not hot enough that I need to add cold water to it and water in bath goes cold very quick.

What settings do I need to change on combi boiler. It's a betacom 2.

Thanks

 

[JohnD]

turn the hot tap down to reduce the flow.

This is how combi boilers work. They are able to heat x litres of water per minute by y degrees.

Increase x, and y reduces. Reduce x and y increases.

For example, some boilers have x as 11 and y as 40.

A less powerful boiler might be 11 and 35

In winter, the incoming cold water from the watermain might be 5C, so 5+40 means your tapwater would be 45C, which is not very hot.

That's combis for you.

If you have a thermometer and want to run some tests, measure the litres per minute at the basin tap, and its temperature; and do the same at the bath tap.

 

[Danblade]

Hi. It takes absolutely forever to run a bath with the hot tap running at max speed, so if I slowed it down i would never get one. Hehe.

 

[JohnD]

fill a bucket at the hot tap, time it, calculate how many litres per minute you are getting. A bath needs in the region of 100 litres (less if you are portly).

Do you know the power of your boiler, in kW? It might be 24, 30, or thereabouts.

Have you got a thermometer?

I wonder if you can detect that I am not a combi enthusiast.

 

[Mottie]

Our first central heating system we ever had fitted in our first house was a Saunier Duvall combi system. Heating was fine but in winter when having a bath, we had to also turn on the cold tap in the sink to slow the flow of cold water through the boiler. Took its time to fill though and on really cold days we had time to boil a couple of kettles of hot water to add to it! When we moved to our second house with a conventional system, the luxury of a tank of hot water, ready to go, was pure joy.

 

[John D v2.0]

turn on the cold tap in the sink to slow the flow of cold water through the boiler.

Agreed with the Combi bath issue. 24kw boiler has a limit set by physics on the flow rate to get a decent temperature.
Turning the hot tap down a bit would have the same effect without having to send clean water down the drain.

 

[ReganAndCarter]

What settings do I need to change on combi boiler. It's a betacom 2.

Have you tried turning the dial up on boiler with the tap symbol?