The Accidental Smallholder Forum

Smallholding => Renewables => Topic started by: juliem on June 20, 2017, 06:30:41 am

Title: Thermostat setting of solar heated water.
Post by: juliem on June 20, 2017, 06:30:41 am
Mine in set at 67c......getting a bit fed up with all these scorching hot water with the heatwave this week . I was told years ago that it was important to heat water to this temp so it would keep me going if you have a few days of cloud.
Title: Re: Thermostat setting of solar heated water.
Post by: cloddopper on June 20, 2017, 07:43:02 am
My pal Pip set up a quite a large solar heating system to heat his 25 x 15 a 4 foot deep swimming pool he had inside a specially made polytunnel . One year he dumped so much heat into it it was decidedly uncomfortable to take a swim in
Title: Re: Thermostat setting of solar heated water.
Post by: mab on June 20, 2017, 08:18:45 am
Max recommended domestic water temp is 60c to avoid the risk of scalding - but yes that will reduce the storage you have a bit.
Another way of doing it is to fit (or have fitted) a thermostatic mixing valve to the outlet of the hot water tank set to 60c, which will mix cold with the hot coming out of the tank if it is hotter than 60c.
Title: Re: Thermostat setting of solar heated water.
Post by: chrismahon on June 20, 2017, 10:33:51 am
You will get scalded above 50C. A stored water temperature of 60C is the legal minimum to avoid Legonella and 65C is considered the optimum. To resolve the scalding issue, which is a legal requirement on Public buildings and rental property, thermostatic mixing valves should be fitted at all the hot water outlets. These mix hot and an amount of cold to achieve a maximum outlet temperature of 50C or less.


I was very surprised when I was told (at Plumbing College) the difference between a cold shower and a hot one was just 5 degrees. 37C for cold and 42C for hot. Thermostatic showers are set to 42C maximum and have an override button which has to be activated to get past that.
Title: Re: Thermostat setting of solar heated water.
Post by: juliem on June 20, 2017, 12:34:02 pm
midday and already creeping up to 52c. My system is about 14 yrs old so I suppose it is quite old fashioned.
Complicated because I have a bore hole which I think is also acting up Don't think I would have solar panels for hot water again....if I had a new house .Too many appliances are cold
fill.
Limited things you can do with hot water in our household...besides washing the car .Washing clothes in the sink/dishes is looked on as medieval by my grown up kids.(including washing hair in the sink)

Move house is the answer....could escape the rooks as well.
Title: Re: Thermostat setting of solar heated water.
Post by: cloddopper on June 20, 2017, 11:21:05 pm
Can you run the cold fills with hot water off a mixing valve ?
Title: Re: Thermostat setting of solar heated water.
Post by: juliem on June 21, 2017, 08:44:37 am
The tank needs replacing anyway...so thats probably the time to have all these things done..have a company lined up in Tenbury tecommended by Stretton Climate Care..new tank is made..so just got to get them out.When is the ideal time of year to get this done?