Tests carried out on 160+ different solar panels by the internationally acclaimed research organisation Solartechnik Prufung Forschung (SPF) found that the gross efficiency of flat plate collectors was considerably higher than evacuated tube collectors…… http://www.sustainability.ie/solar.html
Your Solar Tips:
Flat plate is the most suitable solar technology for human water consumption at approximately 60◦C. When offering your customer the solar solution look at the temperature range required and make sure to apply the correct type solar panel for the application
Using a manifold of evacuated tubes in direct contact with water is lethal. Sooner or later the manifold paths will develop scale, causing rapid decline in efficiency and ultimately complete clogging of the manifold, rendering the whole system ineffective.
The distorted structure of government incentive schemes pushed many Evacuated tube suppliers to oversize their system, causing severe overheating once installed. The overheating of such systems causes a variety of problems such as geyser failures, valves failure, circulation pumps failure, safety problems with boiling water etc. Make sure to verify that the solar system you install is not prone to such problems.
Give your customers sufficient solar capacity to provide for their daily consumption.
Being an active plumber, you often find yourself in a position of having to recommend to customers the correct type of solar geyser installation.
As the South African solar heating market is not yet standardised you are very often exposed to suppliers trying to promote a variety of product and solutions, many of them not tried-and-tested under South African conditions.
Here a number of solar tips which will help you decide on making the right choice for your customers and avoid the frustration of having to deal with unsatisfied customers:
Facts and Figures
Indirect solar geysers use heat transfer fluid (normally glycol) to carry energy from the solar collector and transfer the energy to the water through a heat exchanger. The purpose of using this technique is to prevent environmental damages to solar collectors such as freezing damages, corrosion and clogging.
Natural circulation systems are preferable to pumped systems in many instances due to their relative simplicity, lower cost and higher level of reliability. However, many of these systems fail to operate in a satisfactory manner due to faults related to wrong installation.
Natural circulation in solar geysers is weak in comparison to pumped circulation and is therefore sensitive to wrong system setup.
The following errors are most common:
1. Small leaks of glycol which are not detected during the installation
2. Incorrect pipe slopes, causing local high points and consequent air locks in the primary heating circuit
3. Incorrect glycol filling procedures, leaving unwanted air pockets and causing reduced efficiency
4. Incorrect glycol/water mixing ratios, causing freezing and consequent cracking of collectors
5. Insufficient service intervals – glycol level in Indirect systems should be checked regularly. The recommended interval is once a year. Systems which are not serviced are likely to experience reduced efficiency and ultimately stop functioning.
Your Solar Tips
Following the above principles will prevent comebacks. The tips provided are based on the natural laws of physics and not on municipal by-laws. Therefore, failure to meticulously follow those guidelines will guarantee installation failure, frustrated customers and loss of reputation for the installer and the technology.
Don’t hesitate to contact firstname.lastname@example.org if you require technical assistance