Let's start with a disclaimer: every solar thermal installation project is different, so these are just basic steps to help you on your way. You'll need to consider your specific circumstances at every stage and plan accordingly. Now that we've got that straight, let's look at the first steps in planning a successful solar thermal system!
1. Work out your needs
There's no point planning the installation until you know how much heat you need to produce and what kind of gear that will require. So sit down and do all the energy calculations, collector output calculations, system type choice, solar fluid mix percentages and everything else. Work out the ideal figures and the minimum requirements, so you can see how the reality of your project compares to the on-paper version!
2. Decide component locations
The first thing to do is to take a good look at your home and work out where everything will fit. Start with a load analysis: how much weight can the collector site carry? Normally, this is the roof of your house, but if it's weak, you'll need to consider an alternate site or some reinforcement.
Once you know how much weight the site can hold, work out how many collectors you can fit, bearing in mind their weight and the available space. Hopefully, this will fit somewhere between the minimum and ideal energy production figures you worked out – if not, you'll need to rethink things.
Inspect your home and work out where you will run the pipes from the collectors to the storage tank, domestic hot water system or space heating equipment (depending on the system you're installing). If you need one or more tanks for storage, drainback and expansion, find appropriate sites for them and their associated hardware (pipes, heat exchangers and so on).
3. Make a list of the parts
Now that you have a mental image of where everything will go, it's time to sit down and make a list of all the bits and pieces you'll need. A complete list.
The best way to do this is to sketch the system. It doesn't have to be a work of art, but it'll help you keep track of everything so make it big enough that you can add missed components and notes to yourself as you go along. Once you have the complete sketch, start at one point in the system and work around, listing every item in turn.
You'll need to include:
- solar collectors (how many and what type?)
- collector mounting hardware (what type?)
- pipe runs (what material, what type and how long?)
- flashing for where pipes go through the roof
- pipe insulation and fittings (elbows, trees, unions, hangers, couplers, etc.)
- storage tank (how big?)
- heat exchanger (internal or external?) and any plumbing and fittings
- and so on around the whole system
Notice how picky and detailed the list is: that's deliberate. You need to look at every single tiny detail, right down to the number of screws you need to fix pipe hangers in place... and the anchors to hold