Boiler temp to heat cylinder to 65

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just wondering how hot I need to set the temp stat on my boiler to enable it to heat my cylinder to 65c?

All the info online just says to set the boiler to a hotter temp than the cylinder temp but not how much hotter it should be.

It is a firebird conventional oil boiler with a 3 pipe system, 2 heating zones, Each with its own own stats and all bar one of the rads have trvs.

I think I read somewhere (in that past) that with older (non condensing) boilers running them near max is the best option and that 80c would be needed to get the cylinder up to 65Cs. The other reason I think this is that it ought to reduce cycling and also gives Quicker room heat up times from cold in the morning.

Am I on the right or wrong track??
 
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It is normal to set the cylinder to 55-60 C.

Any hotter risks scalding.

Typically the boiler needs to be about 10 C hotter than the cylinder set temperature.

Tony
 
Cheers tony,

I think the energy saving trust etc use 65c as a recommendation due to it killing legionella instantly- but obviously regularly heating the cylinder to 55-60 stops it growing in the first place. They also mention using a anti scald valve to bring it down to 55c
 
Also- my thermostatic power shower suggests hot water input at 65c for best flow rates.
55-60 seems reasonable until I get an anti scald valve and shouldn't affect the shower too much.

Cheers
 
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i would be very careful setting the cylinder at a set point of 65 degrees c,at that temperature 3rd degree burns occur in about 2 seconds . Set at 60 degrees 90% of any bacteria are killed after 2 minutes.
 
How did we ever cope with gravity primaries whereby boiler temp was in excess of 80c...
 
Or in the "copper" in the corner of the skullery - with a bar of Lifebuoy. A mother's elbow was better than any UV thermometer ;) ( or is it I R )
 
and gas lamps with those very fragile mantles that crumbled if they were touched by the match or taper used to light the gas.
 
So would setting the cylinder at 55 and the boiler at 70 be advisable ?

Or would 60 and 70/75 be better- I want a fast recovery for hot water and the rads to warm the room quickly too.

Cheers.
 
Rads are designed for a flow temperature of 75 C but 70 C is almost as good.

A 10 C differential to the cylinder is adequate.

So set at 55 C or 60 C or anything between.

Tony
 
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