Solar Water - Anyone have it??

Devon_Hippo

ormus wrote: »

building regs say a max 46c temp is required at the outlet taps.
(note this temp is too hot to bathe with).

If you store hot water at a temp of around 20-50c, there is a risk of Leigonnella - in fact at 30-46C it is perfect for max growth :eek:

You should heat stored water to about 55-60C for safety, esp if there are vulnerable people in the household (babies, old people, sick people).
If you want to stop scalding risk by restricting hot water to 46C - which is a very good idea - then the best way to do that is to fit a TMV (Thermostatic Mixing Valve) that will take the 60C hot water and mix it with cold to get to the set cooler temp.
Sure, it sounds daft to heat the water and then cool it, but there is the bug situation that you need to be aware of.
Also, if your household tends to run out of hot water, having it heated to a higher temp will make it go futher

EliteHeat

Devon_Hippo wrote: »

If you store hot water at a temp of around 20-50c, there is a risk of Leigonnella - in fact at 30-46C it is perfect for max growth :eek:

You should heat stored water to about 55-60C for safety, esp if there are vulnerable people in the household (babies, old people, sick people).
If you want to stop scalding risk by restricting hot water to 46C - which is a very good idea - then the best way to do that is to fit a TMV (Thermostatic Mixing Valve) that will take the 60C hot water and mix it with cold to get to the set cooler temp.
Sure, it sounds daft to heat the water and then cool it, but there is the bug situation that you need to be aware of.
Also, if your household tends to run out of hot water, having it heated to a higher temp will make it go futher

Quite right too. To store hot water at anything less is nothing short of dangerous.

Plures, spend £3K+ on solar hot water and save £40-£50 per year - payback is 60 odd years. You would have to be daft or have too much money to invest in this free energy at the moment - wait until the technology improves.

liitleblackcat

EliteHeat wrote: »

Plures, spend £3K+ on solar hot water and save £40-£50 per year - payback is 60 odd years. You would have to be daft or have too much money to invest in this free energy at the moment - wait until the technology improves.

While that may be the case with current gas prices, what do you think is going to happen to prices in the next 60 years now that most countries are importing the stuff from the other side of the world. 10% increase year on year will make current prices seem very cheap.

webwalker

Whoa tigers. Leigonnella needs a stable temperature to incubate and does so in a sub layer of warm water usually in water cooled aircon tanks where the temperature is stable and the water largely undisturbed, if you use your water regularly ie not in a holiday home then the conditions for the bacteria to grow do not exist(no stable temp layer as the water is moving constantly)

EliteHeat

liitleblackcat wrote: »

While that may be the case with current gas prices, what do you think is going to happen to prices in the next 60 years now that most countries are importing the stuff from the other side of the world. 10% increase year on year will make current prices seem very cheap.

This technology is in it's infancy and will get better and better (imo). I would wait for something better.

yourphoenix

We have just been cold called from a company called Britannic Power who claim their Solar System will produce enough energy to completely replace our Oil Boiler - Is this possible ?

EliteHeat

yourphoenix wrote: »

We have just been cold called from a company called Britannic Power who claim their Solar System will produce enough energy to completely replace our Oil Boiler - Is this possible ?

No it is not. Try and get them to put that in writing and see what their response is.