Boiler Temperature

energysavingexp

heating-eng wrote: »

This is incorrect

According to the paper "Legionella and the prevention of legionellosis," [15] found at the World Health Organization website, temperature affects the survival of Legionella as follows:

• Above 70 °C (158 °F) - Legionella dies almost instantly
• At 60 °C (140 °F) - 90% die in 2 minutes (Decimal reduction time (D) = 2)
• At 50 °C (122 °F) - 90% die in 80-124 minutes, depending on strain (Decimal reduction time (D) = 80-124)
• 48 to 50 °C (118 to 122 °F) - Can survive but do not multiply
• 32 to 42 °C (90 to 108 °F) - Ideal growth range
• 25 to 45 °C (77 to 113 °F) - Growth range
• Below 20 °C (68 °F) - Can survive but are dormant, even below freezing

Other sources [16][17][18] claim alternate temperature ranges:

• 60 to 70 °C (140 to 158 °F) to 80 °C (176 °F) - Disinfection range
• 66 °C (151 °F) - Legionella die within 2 minutes
• 60 °C (140 °F) - Legionella die within 32 minutes
• 55 °C (131 °F) - Legionella die within 5 to 6 hours
• 20 °C (68 °F) to 45 °C (113 °F) - Legionella multiply
• 20 °C (68 °F) & below - Legionella are dormant

macman

chopps wrote: »

Is 70 C ok then for the CH ? (and the previously advised 60 C for the hot water on demand setting)

You're not going to get legionella from your CH circuit, unless you plan to start drinking the water from the rads...

heating-eng

energysavingexp wrote: »

According to the paper "Legionella and the prevention of legionellosis," [15] found at the World Health Organization website, temperature affects the survival of Legionella as follows:

• Above 70 °C (158 °F) - Legionella dies almost instantly
• At 60 °C (140 °F) - 90% die in 2 minutes (Decimal reduction time (D) = 2)
• At 50 °C (122 °F) - 90% die in 80-124 minutes, depending on strain (Decimal reduction time (D) = 80-124)
• 48 to 50 °C (118 to 122 °F) - Can survive but do not multiply
• 32 to 42 °C (90 to 108 °F) - Ideal growth range
• 25 to 45 °C (77 to 113 °F) - Growth range
• Below 20 °C (68 °F) - Can survive but are dormant, even below freezing

Other sources [16][17][18] claim alternate temperature ranges:

• 60 to 70 °C (140 to 158 °F) to 80 °C (176 °F) - Disinfection range
• 66 °C (151 °F) - Legionella die within 2 minutes
• 60 °C (140 °F) - Legionella die within 32 minutes
• 55 °C (131 °F) - Legionella die within 5 to 6 hours
• 20 °C (68 °F) to 45 °C (113 °F) - Legionella multiply
• 20 °C (68 °F) & below - Legionella are dormant

You only get it with stored water, as already said you are incorrect

heating-eng

macman wrote: »

You're not going to get legionella from your CH circuit, unless you plan to start drinking the water from the rads...

That would be nice, LOL

energysavingexp

heating-eng wrote: »

You only get it with stored water, as already said you are incorrect

if you have a hot water tank then that is storage and you can get it

heating-eng

energysavingexp wrote: »

if you have a hot water tank then that is storage and you can get it

This person hasn't got stored hot water by the sounds of it.
If they did most plumbers would set it at about 55 to 60 c but only for stored.
70 c is far too hot.

energysavingexp

i was ref to people with hot water tanks not combi systems not to say you cannot have a combi with a hotwater tank as people do with solar hot water

macman

heating-eng wrote: »

This person hasn't got stored hot water by the sounds of it.
If they did most plumbers would set it at about 55 to 60 c but only for stored.
70 c is far too hot.

So why did they say that 'the plumber set the hot water tank to 55C?'?

heating-eng

macman wrote: »

So why did they say that 'the plumber set the hot water tank to 55C?'?

If they are setting hot water temp and heating normally this would be on a combi ?
Unless he has a cylinder set at 55 c and then he is adjusting the flow temp in the boiler,

If you have a cylinder nothing from 55c will be ok.

macman

He's clearly referring to the 'stat on the tank.