Frequently Asked Questions Solar Collector G24

Transcription

1 Frequently Asked Questions Solar Collector G24 The installation and use of the collector is very simple. Here we have tried to answer the questions we get very comprehensively, for those who would like to know more and get inspiration: 1. What is a solar water heater? Solar water heaters also called solar domestic hot water systems is a cost-effective way to generate hot water for your home. They can be used in most climates and the fuel they use sunshine is free. Solar water heating systems include storage tanks and solar collectors. 2. Why should you buy a solar collector? Simple! with a solar collector, you can save costs by becoming independent of external energy for heating hot water. You can install one in your family or summerhouse. You can connect it to your existing water-system. Or reduce your costs by replacing all other water heaters, for your swimming pool, for car wash or just for a separate simple shower. 3. How does it work? They feature parallel rows of transparent glass tubes. Each tube contains a glass outer tube and metal absorber tube attached to a fin. The fin's coating absorbs solar energy and transfer to a copper heat pipes. This hollow copper tube transfer heat very efficiently with virtually no energy loss to the heating water medium. In this water medium is situated the copper coil heat exchanger which is predestinated to heat the consumable water. 4. Will water be heated on a cloudy day? The solar water heater with super heat pipes work also in indirect sunray at high efficiency. The hollow copper tube water vaporize at lower temperatures 30 and the condenser bulbs are designed to reach temperatures of 200 degrees in condenser head. The copper heat pipes and copper coated vacuum tubes can absorb and transfer heat very efficiently with virtually no energy loss (98%). 5. Are solar tube collectors more efficient than flat plate collectors? Yes, besides being the most efficient collector at absorbing the sun s energy, solar vacuum tubes have other advantages. With flat panels the solar rays strike the panels at an oblique angle during the early and late parts of the day and are only perpendicular at midday. The angle plays an important part in the flat panel's collection efficiency. Solar angles (the angle at which the panel meets the sun) plays very little role with solar vacuum tubes as the sun is always striking at an optimum angle. Because of the pure vacuum, there is virtually zero heat loss. This is evident by touching a glass vacuum tube which is cold while the liquid inside can be boiling. Almost 94% of the sun s energy is directed to the inside of the tube and is captured. Flat panel collectors will always loose heat through the glass and they become very inefficient at higher temperatures. Page 1 of 9

2 6. How much money can be saved annually buying the G24? Well, how much do you spend today on heating up water for your shower, hand wash, etc? How big is your household? Typically, if you use an electric water heater, the investment in the solar heater can come back within very few years. If you use gas, a little bit longer. And remember, when your investment is paid back, the heating is free. You don t have to think about energy prices anymore! 7. Is there a warranty on the product? 1 year period of warranty is provided with the product. In case of faulty product the customer can turn to the retailer without the obligation of proving. In the second year customer can still turn to retailer but in this case it is necessary to have the fault proven by the customer. In case of incorrect installation the warranty/guarantee is not valid. 8. What is the advantage of the vacuum tubes with super heat pipe comparing to a nonpressurized open solar vacuum tubes? Non pressurized heat tubes utilize an open vacuum tube and the water is heated internally by the sun and starts the natural phenomen which is known as thermo-siphoning. The advantage of this type of heat system is that there is no costly copper piping involved. The disadvantage is that they can only be used in an open loop system and therefore it can be only used in applications above freezing. Pressurized high performance heat tubes extend the possibilities of solar water heat. The principle is similar to that above except that water does not physically enter into the vacuum tube. Instead, specially designed hollow copper heat pipes are inserted into the vacuum tube. The inside of the heat pipe contains pure water residing within a vacuum. This vacuum means the water inside will boil at less than 30 degrees. Hot vapor rapidly rises to the top into a condenser tube designed to reach temperatures of 200 Degrees Celsius or more. The water in a heat pipe system never actually enters the vacuum tube. This means it can be used in systems involving colder climates. 9. What is in the inner side of the vacuum tube? The solar vacuum tubes is manufactured using a patented 3-layerprocess that results in a coating that can absorb more of the sun's energy while being able to withstand temperatures in excess of 300 degrees celcius without deteriorating. This coating is what makes these solar heat collectors superior to any other collector on the market. The special selective coating change the short wave solar radiation into long wave heat radiation and is almost 94% efficient meaning only 6% of the suns energy is lost! 10. What is the proper orientation/optimal angle of the solar collector? Orientate the sollar collector always southwards. If placed on a flat surface, the collector will be at its optimal angle, i.e. 45 degrees. The optimal angle varies over the season but there is no need to adjust it continuously. The frame can also be cut to adjust to the angle of a sloping roof and the feet moved accordingly. It is important to make sure trees and buildings do not shadow the collector during the day. Page 2 of 9

3 11. What is the required installation height of the G24 solar collector? An installation height is not required because the heated water medium is separated from the consumable water with the heat exchanger copper coil. So this works at your home water installation pressure. 12. How fast will the water heat up? The speed is dependent on the temperature of the heated water medium of the tank, clouds, air temperature, the home consumable water temperature, etc. In the sunny period of the year the temperature of the heat pipe in the collector will generally increase very fast (also in the morning) and to a very high temperature, which will be transfered to the 200 liter heated water medium of the tank. This will generally increase the water degrees per hour. This means the system has the capacity to reheat to high temperature the inside tank water medium 2 to 3 times a day. Example: If the water to be heated up is degrees, the outside temperature is 30 degrees; and there is full sun available, as for example in July and August, then the tank water can be full heated (more than 60 C) for 3 times during 12 hours. 13. How fast will the heating water temperature decrease in the tank? It depends on several factors, but in general it will decrease a total of degrees during the night. Or an average of 1 degree Celsius per hour. This graph is an example showing the general change of temperature in a household where water is also consumed. Vízhőmérséklet változása ( C) Changing of water-temperature 1:00 2:00 3:00 4:00 5:00 6:00 7:00 8:00 9:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 0: What is the pressure of the water coming out of the collector? The coming out water pressure is the water inlet pressure of your home system, because the 16 mm diameter heat exchanger copper coil has no pressure-losses. 15. Can G24 solar collector be used in winter conditions? The solar collector tank vacuum tubes and filling valve can thanks to the good thermoisolation withstand to -15 C degrees, but the fittings and water hose/tubes are Page 3 of 9

4 exposed to freezing hazard to the roof and in the loft, so therefore it is unadvisable to use it in winter conditions. So we recommend to drain the water away from the solar collector in the winter months. 16. How do I protect my solar system during sub-zero temperatures? The water in a heat pipe system never actually enters the vacuum tube. The copper collector only holds a small amount of liquid with anti-freezing mixture. This means it can be used in systems involving colder climates, therefore the tank water medium is separated from the consumable water and heated with copper pipe. But in this situation, for sub-zero temperatures, you must use antifreezing mixture in the water tank, thermo isolator water hose and to winterize all fittings and water tubes with special thermoisolator sponge wrapping. 17. Why is there no heating element installed inside the G24? A heating element has to be fairly big to heat this amount of water. It will need a controller - and it will also consume a lot of energy which is not our idea of an efficient solar collector. Secondarily, this is a solar collector where you don t need to put wires of 220 Volt up on your roof to your collector. 18. Does G24 need regular maintenance? No. The collector is built to last a minimum of 15 years. The collector is hermetically sealed inside an evacuated glass tube, eliminating convection and conduction heat losses and isolating the collector from adverse ambient conditions. The water heating medium in the tank use a 300 mm long magnesium rod against water-scale and corrosion. If the water being used for a very long period of time and the magnesium rod wears-out, the pipe caps can be covered with sedimentation, reducing efficiency. In this case a few litres of vinegar poured into the tank (through the top-ventilation hole) and then flushed through the system (exactly as you can do with a water-kettle) solves the problem (open the drain pipe to rinse). Change the run-down magnesium rod easily from tank side and after refill the tank with water. Be sure not to use toxic cleaning chemicals, keeping the environmental hygiene! 19. Does G24 need regular cleaning? Rain will clean the outside of the round tubes. The glass tubes don t need to be opened and cleaned inside - see question above. The conformance of normal home water system is adequate. 20. What precautions do I need to take if I m using a solar collector? Caution!- During the installation and operation of the solar collector make sure children are kept out of the way. Caution!- Don t touch the copper heat pipe head when you install the vacuum tubes because even at very low sunrise, sunset or cloudy days it can reach very high temperatures. In sunshine more than 200 C!!! Page 4 of 9

5 Caution!- Danger of burns! The temperature of the water heated by the collector can reach 100 C, therefore always make sure the hot cold water mixing is adequate when opening the tap. Caution! The solar collector has to operate as an open system. The ventilation valve in the top must never be closed. The tank itself must not be put under pressure or vacuum. Caution! The sensor temperature/water level sensor cable must to be fixed to the tank body to prevent the breakage in windy weather. 21. What about hail & strong wind? The glass tubes can withstand hailstones up to 25 mm in diameter. And the rounded surfaces of the design channels wind away so it can withstand very strong winds. Wind resistance is 30m/s (grade 11). 22. What s in the package? a. 200 liter Tank b. Frame c. The frame package contains screws and the 24 pcs bottom tubeholder caps. d. The 2x12 pcs super heat pipes in 2 packages. e. The RF 4 automatic valve. f. The RFC-JC solar water heater display set. g. The water tank package contains also the 24 pcs plastic dust proof rings for vacuum tubes, the sensor pipe, the inlet pipe, the air-vent pipe with cap, the drain screw-cap and the blind magnesium hole plug. h. Thermal conductive gel. i. The instruction book. 23. Questions for the sensor and display The RFC-JC display can operate automatically. The sensor cable lenght is 30 m and it will be inserted in a protection internal pipe. The sensor temperature/water level sensor cable should be fixed to the tank body to prevent the breakage in windy weather. Accuracy of temperature measuring: +/- 2 C. Range of temperature measuring: 0 C 99 C. Five classes water level display. 24. How should the system be installed? There are several ways of connecting the system. It works with standard ½ fittings, which you can buy everywhere. It can be installed as a separate system or it can be built into your existing system. The system can also be a way of preheating the water before it goes into the water-heater, reducing the heating required by your electric heater. Our main target-group is focused on the simplest installations. We can provide some general diagrams that can give inspiration to other solutions. The G24 water heater does not need to be installed on the roof because it is working at your home installation pressure. Page 5 of 9

6 Example of installation on roof which already have the right angle: Page 6 of 9

7 Example of extra materials for installation on roof: FIX KB ball-bearing ½ 2 pcs ½ imp. Ball-bearing Hollander 2 pcs COMISA tube with blue insulation COMAP connector 16x1/2 with KM grummet COMAP connector 16x1/2 with BM grummet Copper-bolt 1/2 M 8x30 bolt M 8 female screw (nut) Hilti band 26x1,2 size 8 25 m 3 pcs 4 pcs 3 pcs 10 pcs 10 pcs 1000 cm Page 7 of 9

8 25. What installation types do you recommend? Swimming Pool Overflow Air Vent Regulating valve (30-60 l/h) The outgoing water tube should be placed to the bottom of the pool, to avoid trouble caused by hot water. Pumping station (max l/h) Non-return valve Bill of material for collector installation for heating the pool Pumping station (max l/h, 600 W) Regulating valve 1/2 Non-return valve 1 Ball-cock 1/2 ALPEX tube 20 ø Threaded connector KM 20x1/2 Threaded connector BM 20x1/2 Threaded connector KM 20x3/4 Tightener KB 1 3/4 Tightener KB 1 1/2 min 2* 4 m 2 pcs. Page 8 of 9

9 Hot-water change between solar collector and boiler Gas or electrical boiler Automatic mixing valve max 60 C Normal Home water system usable hot water Benefit: The thermostat in the el. boiler will switch on if not hot enough. And you can therefore extend season with the collector. Minus: your electrical boiler is still connected. Water heating system with condensing turbo Steamboiler and hot water Tank with indirect heat-exchanger Air Vent Hot water tank with indirect heat-exchanger Automatic water valve Overflow Condensing Turbo Steamboiler Automatic mixing valve max 60 C usable hot water defroster tap Automatical assistants with steamboiler for water heating Home water system Page 9 of 9