Solar panel, thermostat locations & water temp! PLUMBERS!
Discussion
Hi, we've recently had our house completely renovated complete with Worcester Bosch mains hot water cylinder and solar system.
Originally the boiler thermostat was at the bottom of the tank and the solar thermostat in the middle. This seemed to result in the boiler staying on almost continually as it tried to heat up 300l of water. Also the water temperature at the tap was much hotter than the thermostat setting.
I then read the tank manual and realised the boiler thermostat should be in the middle. This has given me much more accurate control over the water temp. Unfortunatlely it meant the solar sensor had to go in the top location. I believe this turns the solar off much too soon as the instructions say it should be at the bottom of the tank.
I'm concerned that if i move it to the bottom then i could end up with very hot water in the top of the tank, above 60 degrees and the solar still pumping.
Do I just need to get a mixer valve fitted to the tank in order to regulate the tap temperature and then move the solar sensor to the bottom location?
Sorry for al the questions but our channel islands location makes expertise hard to find!
Originally the boiler thermostat was at the bottom of the tank and the solar thermostat in the middle. This seemed to result in the boiler staying on almost continually as it tried to heat up 300l of water. Also the water temperature at the tap was much hotter than the thermostat setting.
I then read the tank manual and realised the boiler thermostat should be in the middle. This has given me much more accurate control over the water temp. Unfortunatlely it meant the solar sensor had to go in the top location. I believe this turns the solar off much too soon as the instructions say it should be at the bottom of the tank.
I'm concerned that if i move it to the bottom then i could end up with very hot water in the top of the tank, above 60 degrees and the solar still pumping.
Do I just need to get a mixer valve fitted to the tank in order to regulate the tap temperature and then move the solar sensor to the bottom location?
Sorry for al the questions but our channel islands location makes expertise hard to find!
Here's ours (crappy iPhone pic, sorry):
The solar panel feeds water in at the bottom, and the bottom stat connects to the solar panel controls. Both the other stats connect to the main heating controls. When we moved in, it was wired up back to front so the boiler would only kick in once the solar panel had heated it up to about 40deg which was, of course, useless.
The solar panel feeds water in at the bottom, and the bottom stat connects to the solar panel controls. Both the other stats connect to the main heating controls. When we moved in, it was wired up back to front so the boiler would only kick in once the solar panel had heated it up to about 40deg which was, of course, useless.
Ricky_M said:
You can adjust the target temperature on the control centre, lower it to 50 degrees if you are worried. I always put the sensor in the bottom pocket.
There should be a high limit stat at the top of the cylinder to prevent overheating.
There is no stat at the top.There should be a high limit stat at the top of the cylinder to prevent overheating.
When the boiler stat was at the bottom it was recording a very low temperature despite the top of the cylinder being around 70+ degrees. I'm just concerned that the thermostats bare no relation to the actual water temp in the TOP of the tank.
Solar hot water is all about controls.
With a single cylinder and solar it's difficult to have high efficiency and hot water all the time. The solar itself should have two thermostat controls, when the differential between the one in the panels and the one at the bottom of the cylinder is say + 5 degrees the pump should switch on.
To avoid heating hot water, thermostats for backup heating should be about half way up.
With a single cylinder and solar it's difficult to have high efficiency and hot water all the time. The solar itself should have two thermostat controls, when the differential between the one in the panels and the one at the bottom of the cylinder is say + 5 degrees the pump should switch on.
To avoid heating hot water, thermostats for backup heating should be about half way up.
caziques said:
Solar hot water is all about controls.
With a single cylinder and solar it's difficult to have high efficiency and hot water all the time. The solar itself should have two thermostat controls, when the differential between the one in the panels and the one at the bottom of the cylinder is say + 5 degrees the pump should switch on.
To avoid heating hot water, thermostats for backup heating should be about half way up.
This is exactly what i'll have tomorrow! The main problem is they were put in the wrong places and the wrong way around to begin with it would seem! Solar half way up, boiler control at the bottom!With a single cylinder and solar it's difficult to have high efficiency and hot water all the time. The solar itself should have two thermostat controls, when the differential between the one in the panels and the one at the bottom of the cylinder is say + 5 degrees the pump should switch on.
To avoid heating hot water, thermostats for backup heating should be about half way up.
Are you sorted out with this now?
I've installed this:
http://www.deddington.org.uk/forum/index.php?topic...
How's your system working now?
I've installed this:
http://www.deddington.org.uk/forum/index.php?topic...
How's your system working now?
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