Tips for Planning Your Solar Hot Water Installation
Measuring for Solar Hot Water Panels
As with any project, a few minutes of planning will save hours of fixing.
Start your solar hot water system installation by measuring the angle of the collector mounting surface from south with a compass. (Be sure to correct for the magnetic compass error in your region.)
It is highly preferable that this angle be within 20 degrees of south for installations in the northern hemisphere. The greater the angle is away from south, the less solar energy will be collected.
The placement of the solar hot water panels and the tank should be determined as well as the routing for the piping to all components.
The collector tilt angle varies according to the application and latitude. For year round applications such as domestic hot water, or combined space heating and domestic hot water, the tilt should be the latitude + 10 degrees, which is approximately half way between the highest summer sun and the lowest winter sun at noon.
For special applications, such as vacation retreats used only in the summer, a tilt equal to the latitude is best. For retreats used only in the winter, a tilt of latitude + 20 degrees is best. The tilts are not critical and variations of +/- 5 degrees probably cannot be detected. Holocene Technologies supplies legs of several lengths to assist in tilting collectors.
Measure the roof slope and select the leg length needed for the approximate collector tilt from Table 1.1.
Table 1.1 Collector Leg Length Selections (for an 8ft-tall Collector)
In addition to standard tools and plumbing parts, the following will be needed for a typical installation:
- 3 inch hole saw
- Silicone sealant
- Two neoprene roof flashing boots, OD to fit pipe insulation (2½ inch or 3 inch typical)
- 95/5 plumbing solder
- Two 3½ x 3/8 inch SS frame bolts per collector
If you have any questions or want to share any of your own tips for planning the installation of a drain back solar hot water system, please use the comment box below!