Step 1: Selecting What Type of Collectors to Use
Step 2: Sizing Your System
Step 3: Storage or No Storage?
Step 4: Positioning the Solar Collectors
Step 5: System Components
1. Piping- A solar system can reach get hotter than 400 F, so you should never use PEX piping on the loop. Only copper or special solar stainless steel piping should be used. Flexible solar stainless steel piping is commonly recommended because it's easy to use and comes pre-insulated with sensor wires, which makes installation much easier. This type of pipe uses special ceramic gaskets that can withstand temperatures up to 600 F. These system don’t require soldering, so they're great for people who aren't experienced with plumbing.
2. Solar Heating Fluid- In order to move the solar energy from the collectors to the home, you need special glycol heating fluid. Glycol heating fluid is used instead of water so that the system will not freeze in cooler temperatures. Choose a glycol heating fluid designed for solar applications, so it can withstand the high temperatures that a solar heating system can reach.
3. Pump Stations- The pump station is the main mechanical component of the solar heating system. The pump is use to circulate the heating fluid from the collectors into the home. The pump station also contains other key components, such as fill and drain valves, the air purge valve, shut off valves, the flow meter, and the safety pressure release valve and expansion tank connection.
4. Expansion Tank- The expansion tank is an important part of a solar space heating system, but it often gets overlooked. The expansion tank is used to buffer the volume of heating fluid in the system as the heating fluid expands. The hotter the system, the more the fluid will expand, so it's pushed into a pressurized rubber bladder found in the expansion tank. As the system cools off during the night, the expansion tank pushes the fluid back into the system. This way the system volume can change from hot to cold without being damaged.
5. Controller- The solar controller is a differential controller, and measures the temperature of the system at different locations, and activates or deactivates pumps based on solar heating logic. The controller will measure the heating fluid in the collector via a temperature sensor and compares this to another sensor in the storage tank or in the home heating loop. If the collector is hotter than the second reference sensor, the solar pump will be activated to move the heat fluid to the heating zone. If the temperature in the collector drops below the reference sensor then the pump will stop, since there's no solar gain to be had.
Step 6: Excess Heat in the Summer
That's all the tips for planning out a solar heating system I have for you; I hope you found them useful!