Under floor heating questions

[jmdraft]

I’m not sure if this is the right forum, but………..

I have an off grid solar house at 9000 ft. I’m only there in summer but (at altitude); it gets cold at night, so I’ve been thinking about a little under floor solar heating. Basics: I know there has to be a heat source e.g. solar water heat panels on the roof, a pump or pumps for moving the water around, probably some kind of thermostat, tubes or mats for the hot water under the floor and, maybe some kind of holding tank between the heat source and the under floor tubes etc.

What I need to understand is the automatic parts of all this. How do the pumps know when to move the water (Some kind of trigger in the thermostat……..solenoid) from the heat source to the (if there is one) holding tank? How do they know when, how fast etc. to circulate the water in the floor tubes, when to replace it etc. Does it go back to the heat source for reheating………..or to the tanks, what, etc.

I’m looking for some kind of diagram/explanation of how all this works. Any suggestions e.g. websites, links etc.?

 

[Dana]

If you looked at the up front costs of ANY active solar solution for an off-grid application you'd soon come to the conclusion that improving the passive solar solution with better air-sealing, and higher-R insulation would be the better way of keeping the place warm over night. This goes triple for a place you're only using in summer.

If you're truly bent on cobbling up an active solar solution, poke around on builditsolar.com for examples of what it takes.

 

[Sponsor]

 

[Raspy]

What I need to understand is the automatic parts of all this. How do the pumps know when to move the water (Some kind of trigger in the thermostat……..solenoid) from the heat source to the (if there is one) holding tank? How do they know when, how fast etc. to circulate the water in the floor tubes, when to replace it etc. Does it go back to the heat source for reheating………..or to the tanks, what, etc.

I’m looking for some kind of diagram/explanation of how all this works. Any suggestions e.g. websites, links etc.?

The solar collector pump is controlled by a differential controller that measures the temp of the panels and compares it to the storage temp. When the panels are warmer, the pump runs and the storage warms up. When the house needs heat, as determined by the house thermostat, the floor circulator runs and exchanges the heat from the storage tank to the radiant floor. Of course, there is more to it because of freeze protection and closed loop heating schemes, but that is the essential process.