Flow temperature

31 Dec 2012
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United Kingdom

First a little about my system

Glow worm40ff boiler
open vented y plan
hot water cylinder
2 tanks in the loft
Grundfos 15/50 pump
7 radiators
normal 3 bed semi

I am trying to understand how i affect my flow temperature from my boiler and the affect it has on heating my radiators and hot water cylinder.

My boiler has a knob on the front saying max and min which i presume is the boiler thermostat?

If i turn the knob to max does that increase the flow temperature?

If that does increase the flow temperature does that mean that my radiators and hot water cylinder would heat up quicker?

What should the boiler thermostat ideally be set at?

Thanks as always.
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It needs to be set at a minimum of 70 C while heating the water if you have the cyl stat at 60 C.

For heating, the hotter the rad the hotter the room will get and the faster the room will heat up!

But this should all be in the FAQ on this site!

Your boiler is quite old and quite simple, the min and max settings on your stat control are the temp that the boiler will reach then the burner will cut off, as a rule the lower you can have this set at and you are happy with the perfomance of your rads and HW then the cheaper it should be to run, newer boilers are a lot more complex and dont always follow this simple rule, in the end only you know how hot or cool your family like your house to be
Thanks for the replies,
If I am understanding it correctly does that mean that if the boiler thermostat is set to low then that means that the hot water will never get hot enough and the central heating thermostat will never be satisfied because the boiler thermostat will cut the boiler out before any are satisfied?

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No not at all, lets say the boiler stat is set at say 75C and your HW tank stat (cylinder stat) is set at say 60C then wont be a problem but if your boiler stat is set at 50C and your HW tank stat set at 65C then it will never get hot enough to satisfy the HW stat
Ok that makes perfect sense for the hot water.
So the boiler thermostat being set to low does not influence the central heating room thermostat not reaching temperature?
It's also a bit difficult to know what temperature mine is set at as it only has a maximum and minimum setting!
Thanks again for your replies.
The central heating room thermostat measures the temperature of the room that it is situated in and once that room reaches the desired temperature it switches off the complete central heating circuit until the room containing the room stat drops temperature then the whole system comes back on, not a great way to control your house but that is how it works
So the boiler thermostat being set to low does not influence the central heating room thermostat not reaching temperature?

If the boiler stat is not set high enough, the rads might not get hot enough, to make the room warm enough, to satisfy the room stat, if you see what I mean :?:

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