Sand Battery Solar Water Heating Collector DIY version 2, How it's made.

For anyone who doesn't know this cheap DIY heating circulation system is intended to heat my greenhouse raised and insulated beds next winter.

This solar water heater will work in conjunction with my compost piles, which have also been converted via internal heating pipes into a heating source to supplement the heating which this solar water heater will also provide.

Daytime heating is provided by the solar sand battery and sun facing heating pipes in conjunction with the compost heating source, while night time heating will be provided by the compost heating system.

The goal is to grow tropical vegetables during winter, such as Ipomoea aquatica 'kang kong'.

This version has one continuous loop of aluminium pipe, swaged and solder joined together, with flux cored solder.

I detail how to solder join aluminium pipes using a few different solders such as aluminium brazing solder 4043, low temperature 400 degrees aluminium solder, and also standard plumbing solder.

I detail how to anneal aluminium pipes, using a vivid, and how to bend aluminium pipes by annealing and then filling with sand.

I show how I've swaged the aluminium pipes DIY style.

I pressure test the system DIY style.

this system is a big improvement on the first build, having no plastic, and one continuous loop.

I will test the system out after I build the new dual pile compost heating system.