I am looking at adding solar hot water to our place and was hoping to get some help with the design theory.
The current hot water system is roughly set up like this:
There is an oil boiler that heats water for 7 zones. The first 6 zones are radiant heating in the house. The 7th "zone" is a 40gal DHW storage tank. When one of the thermostats in the house, or the DHW storage tank, requests heat then the pump for that zone and boiler kick on. It appears to be a closed loop with a cold water inlet (not pictured) to keep the system topped off.
My first thought is to just replace the existing DHW storage tank with a larger tank that has 2 heating elements. Then connect the boiler to one element and the solar hot water to the other. Something like this:
I've run across a few designs like this so I don't think I'm too far off. The idea is that the solar collectors will keep the DHW tank heated most of the time but the boiler can kick in to supplement our DHW needs if it's cloudy or whatnot.
But what if I wanted to also heat/pre-heat the water for the radiant heating to stop burning as much oil? (Assuming the solar collectors are large enough.)
I've had a few ideas like adding a small tank to the boiler's system and using excess heat after the DHW solar heating element to heat that 2nd tank. Or maybe leave the existing small DHW tank in place and add a large tank to the boiler's system and just pre-heat all of the water via the solar collectors?
Anyone have a similar setup or thoughts on such a system?
Thanks in advance
The current hot water system is roughly set up like this:
There is an oil boiler that heats water for 7 zones. The first 6 zones are radiant heating in the house. The 7th "zone" is a 40gal DHW storage tank. When one of the thermostats in the house, or the DHW storage tank, requests heat then the pump for that zone and boiler kick on. It appears to be a closed loop with a cold water inlet (not pictured) to keep the system topped off.
My first thought is to just replace the existing DHW storage tank with a larger tank that has 2 heating elements. Then connect the boiler to one element and the solar hot water to the other. Something like this:
I've run across a few designs like this so I don't think I'm too far off. The idea is that the solar collectors will keep the DHW tank heated most of the time but the boiler can kick in to supplement our DHW needs if it's cloudy or whatnot.
But what if I wanted to also heat/pre-heat the water for the radiant heating to stop burning as much oil? (Assuming the solar collectors are large enough.)
I've had a few ideas like adding a small tank to the boiler's system and using excess heat after the DHW solar heating element to heat that 2nd tank. Or maybe leave the existing small DHW tank in place and add a large tank to the boiler's system and just pre-heat all of the water via the solar collectors?
Anyone have a similar setup or thoughts on such a system?
Thanks in advance