Hot water issues

[jonathanhall]

hello can any one help?

My boiler is 5 years old often serviced and looked after.
my hoit water is only really hot when you turn the hot tap down loads to a slow flow, then the water gets red hot, if you turn the tap fully on again it goes luke warm (to cold for a bath)
Please if any one can help that would be great many thanks.

 

[joe-90]

Have you switched the water temp up on the boiler? The water in is much colder at this time of year.

 

[Agile]

Your posting means nothing without an exact boiler model and a flow rate!

The boiler is probably working fine but is not reaching your unjustified expectations!

Tony

 

[bengasman]

Have you switched the water temp up on the boiler? The water in is much colder at this time of year.

Does the ""-"" before the 90 relate to your iq?
Turning up the temperature when it is colder has no effect on this problem.
As Tony said, the flow is just higher than the boiler can handle; common problem with smaller combis in winter.

 

[joe-90]

Don't be a dope.

 

[Dan Robinson]

Stop posting stupid advice then.

 

[joe-90]

Checking that the boiler is on maximum hot water settings in winter is good advice. Many people don't realise that a boiler is less efficient in winter than summer. Sadly, you are one of them.

 

[Dan Robinson]

Sadly, well not actually - it fricking hilarious you don't seem to understand what a thermistor does.

If the boiler hot water stat is set to 50 (for arguments sake). Turning it to 60 isn't going to make the hot water any hotter if the boiler can't get to 50 in the first place.

Now, go and sit in a dark room and think about it for a while.

 

[bengasman]

Checking that the boiler is on maximum hot water settings in winter is good advice....

When you finally find out one day that the dhw control on a combi is only driven by the dhw OUTLET temperature, you'll realise how dumb your advice is.
Provided the boiler is installed correctly and not defective (and of sufficiently large capacity for the required flow), it makes absolutely no difference whether the outside temperature is 40°C or -5°C; the temperature at the tap will be exactly the same if you leave the dhw boiler control in the same position.

 

[joe-90]

I'm well aware of what a thermistor is and how it works.

What if the OP has the hot water setting turned down but doesn't realise it?

 

[mrgas]

Checking that the boiler is on maximum hot water settings in winter is good advice. Many people don't realise that a boiler is less efficient in winter than summer. Sadly, you are one of them.

I didn't realise a boiler was less efficient in winter.
Can you tell me why that is please.

 

[bengasman]

...Now, go and sit in a dark room and think about it for a while.

What? No dunce-cap?

 

[joe-90]

Checking that the boiler is on maximum hot water settings in winter is good advice. Many people don't realise that a boiler is less efficient in winter than summer. Sadly, you are one of them.

I didn't realise a boiler was less efficient in winter.
Can you tell me why that is please.

The temperature of the water entering the boiler is lower - hence the temperature differential is greater. Schoolboy physics.

 

[bengasman]

What if the OP has the hot water setting turned down but doesn't realise it?

Judging by the OP's statement about the water being "red-hot" on low flow, that is somewhat unlikely.
Duh.

Dunce-cap.
Corner.
Now.

 

[joe-90]

What if the OP has the hot water setting turned down but doesn't realise it?

Judging by the OP's statement about the water being "red-hot" on low flow, that is somewhat unlikely.
Duh.

Dunce-cap.
Corner.
Now.

The lower the flow the less water the boiler has to heat for the calorific value of the gas consumed. Come on guys - surely you understand the simplest of simple concepts. Oh well, judging by the way you misdiagnose year in year out I guess not.