We offer a 5 year warranty on the panels and all other components against component failure and defects in workmanship and materials. Not covered is breakage after delivery, damage due to lightening strikes, storm damage etc.

Vacuum flasks have a design life of 20 to 25 years, after which the flasks themselves may lose their vacuum. However, these are relatively cheap to replace and are a standard size so they are interchangeable with other brands and can reasonably be expected to be available from numerous suppliers.

We recommend that the 20tube panel is used with cylinders between 135L and 160litres, and the 30tube panel is used with cylinders up to 240litres. Larger cylinders can be heated with 2 or more panels, and it is possible to add an extra panel to benefit from higher temperatures in the winter. In fact, if you fit a smaller cylinder, you will have hotter water, but of course less of it. We would recommend fitting a tank of 135litres if you prefer a smaller amount of hotter water.

An interesting and popular option is to put a smaller cylinder in and set the controller to allow this cylinder rise to 75 degrees - but you MUST fit a thermostatic mixing valve on the outlet to bring the temperature back down and prevent scalding. This increases the effective heat storage and at the same time, on partially cloudy days you are more likely to have water at an acceptably high temperature

This varies according to the time of year - in summer we get almost 10times the amount of solar energy that we do in the winter. In the summer, you can expect to get at least 4kWh of heat per day from a single 20tube panel, whereas in December you can expect only 0.4kWh per day on average. Even in the winter, it is possible to preheat the water to 40C or more if the sun comes out. In fact, if you fit multiple panels, it is possible to heat your hot water to 100C in January (we have seen this in Cornwall).

This depends on the size of the cylinder you chose, and the amount of water you use. A smaller cylinder will be heated to higher temperatures, whereas a larger cylinder will heat more water, but not to the same extent. Systems are generally designed to heat water to 65C or so, although during the winter, it may be necessary to ‘top-up’ the heat on less sunny days. Large arrays, running high temperature solar antifreeze at high pressures can be designed to achieve temperatures of 170C or more!

Panels should be sited on a south facing wall or roof. In fact, anywhere between South-West and South East will give good results. If you are limited to an East-West facing system, then you will need two panels to provide the same amount of hot water as a single south-facing roof slope. The most frequent solution to this problem is normally to mount one panel on the east slope and a second panel on the west slope. A special controller is available for East/West facing installations.

The panels should be mounted at the angle of your latitude. In Ireland, this is approximately 52 degrees. This is AVERAGE optimum angle. In fact, in winter the optimum angle is 15degrees steeper, whereas in the summer it is 15 degrees shallower. The panels will function anywhere between 15 and 90 degrees angle of inclination. This is actually academic, a variation of 15 degrees will make very little difference to the output, so most people simply settle for whatever angle their roof slope is. The extra cost of trying to stand panels off the roof to achieve better efficiency would probably be better spent on purchasing a second panel!

Yes, spares are always available, should you need them. With no moving parts, it is very unlikely that you will need to replace anything, . However, it is not possible to post a replacement tube, so you will need to collect it. The tubes are made of borosilicate glass (aka ‘pyrex’) so they are actually very tough.