need help on solar central heating project

[salpap]

hi i live in greece, crete actually my husband and i live in a top floor apartment so the cost for central heating for our flat is quite high we are the last ones to receive the heat and the first to lose it. Here on Crete even during the winter most days we have sun enough to heat our hot water tank and more if we had any. we already have a solar water heater and have now put up more solar panels so we use those to heat the water for the radiators during the day. could anyone help us with the plumbing side my husband can easily install everythng we are just not quite sure what we need. i dont know if i could post a diagram here as it would make things a lot more easy to explain, but here gos.
what we really need to know is what we need to install in between the solar panel heaters and the main heating pipe going in to the apartment. we will need a shut off valve that shuts off the main gas central heating pipe when our solar heating bumps in, we will need a circulation pump that will circulate the water when its hot into the radiators. would we be better off also having a storage tank to store the water so we could use it in the evening. i know this is not a very good explaination but i need to keep this simple as we are just starting out and will get there step by step if any one can help

 

[gas4you]

In your instance I would suggest you look at a solar thermal store system.

The solar will heat the store, so giving you hot water and some heat to the rads in one unit.

If you google solar thermal store you will find some good info.

Avoid anything made by gledhill though, although no doubt Crete must have their own manufacturers.

 

[Agile]

You can only use solar heating during the hours of sunlight ( when you are unlikely to need it much! ).

Any thermal store capable of storing enough heat for say 6 hours woulkd need masses of water to hold the heat and the weight would not be appropriate for a flat even if you had the space.

Places which build in a thermal store in the basement usually have about a minimum of about 20m³ of water to store the heat. Thats very heavy!

Tony

 

[salpap]

hi thanks for the replies we already have hot water from a solar water heater and we want to keep that seperate from the radiators. so really we only need to heat water for them,and as i said we have already installed the solar panels for this purpose. we originally thought to let the hot water circulate freely during the day as even if its sunny you still sometimes need to fire the central heating once or twice as its colder in the house than out and just use the gas central heating in the evening. so we were thinking that all we needed to install was a pump to help circulate the water though we are not sure even that is neccessary as maybe it would circulate naturally. but we are not sure about the valves. we were thinking of installing manual valves we could leave them open all the time and just close them when we want to use the main gas central heating but somebody told us you can get electronic valves that would automatically open and close accordingly. but then i thought if we also added a storage tank that we could save the hot water in during the day if we didnt need the heat then we could use it in the evening. we are not looking to replace the main gas central heating just trying to find a way not to have to use it all the time. we actually measures how much water one radiator holds and calculated that our radiators altogether hold 200 litres, thats about what a normal hot water tank holds so we were thinking of installing another hot water tank with the new panels and using that for storage but then the valves and pump stay getting complicated thats what i am asking about if any one has any ideas

 

[Agile]

If you fed the radiators from a 200 litre tank of hot water then that would keep the radiators warm for about an hour if you were lucky!

Tony

 

[salpap]

thats all we need we close the house about 6 o clock in the evening and if we had just 1 hour of the radiators open the house is warm until about 9 or 10 clock so then we would only need to use the main gas central heating maybe once after that until we go to bed.