Working principle, classification and installation method of solar water heater

Solar water heaters convert sunlight energy into heat energy and heat water from low temperature to high temperature to meet people's needs for hot water in life and production. According to the structure, solar water heaters are divided into vacuum tube solar water heaters and flat-plate solar water heaters. Vacuum tube solar water heaters are the majority, occupying 95% of the domestic market share. Vacuum tube type solar water heater is composed of collector tube, water storage tank and bracket and other related accessories. The conversion of solar energy into thermal energy mainly relies on collector tubes. The collector tube uses the principle that hot water floats up and cold water sinks, so that the water can be micro-circulated to achieve the required hot water.

Classification of solar water heaters:

1. From the heat collection part, it can be divided into: vacuum glass tube solar water heater and metal plate solar water heater.

2. In terms of structure, it can be divided into: ordinary solar water heater and split solar water heater.

3. According to the pressure of the water tank, it can be divided into: pressure-bearing solar water heaters and non-pressure-bearing solar water heaters.

4. According to its water flow direction, it can be divided into: circulation type, direct current type and integral type solar water heater.

5. According to the access method, it can be divided into: according to the access method, it can be divided into: dry type, flat type, vacuum tube type, heat pipe type, split type (wall-mounted type) {according to the pressure bearing capacity, it can be divided into pressure bearing type type and non-pressurized type}, embedded

How solar water heaters work:

1) Temperature difference control collection cycle

The collector thermometer and the water temperature sensor are placed in the solar hot water floor heating system, which can absorb the solar radiation well and promote the temperature of the collector tube to rise. When the value is set, the circulating pump sends the cold water in the central water heater into the collector through the instruction issued by the detection system. However, after the water is heated, it returns to the water tank again, so that the water in the water tank reaches the set temperature.

2) Floor heating pipeline circulation system

This system is to increase the hot water circulation pump as a different point, and then better control the circulation of the floor heating pipeline through the controller as the working principle. Then, when the water temperature reaches the set temperature, the floor heating circulation pump is automatically started, so that the high-temperature water is circulated indoors through the floor heating coil, so that the indoor temperature is continuously increased. If the water temperature of the water tank starts to be lower than a certain set value, it is the best way to automatically stop the circulating pump of the floor heating pipeline.

Mounting brackets:

1. Select the installation location. Generally choose the roof, the direction is from north to south, 5~10° from south to west to ensure that there are no obstructions. The plumbing to the home should also be reduced, which increases the amount of sunshine.

2. Assemble the bracket. When installing, you should assemble the front piece and the back piece together according to the instructions, and then use a wrench to tighten the screws without loosening. Then, support the front and rear side of the installation diagonally to strengthen the structure.

3. After the water tank and vacuum tube are installed, check all the screws and then tighten them.

Fixed bracket:

Generally, cement piers, expansion bolts or steel wire ropes are used to fix the bracket. Of course, it is necessary to choose the best fixing method according to the situation of the own roof. Wire rope fixing method: Put the wire rope or large steel bars on the left and right frames of the front bracket and the left and right u-rings of the bucket holder, and tighten them with nuts. Select an appropriate location, drill holes and press the expansion hook, and firmly connect the steel wire rope or steel bar with the corresponding expansion hook U-ring.

Install the tank:

1. Installation of electric heating. First open the dustproof and thermal insulation cover of the electric heating port, loosen the screws inside, then pry open the plug at the bottom, check the built-in sealing rubber ring to see if it is tight, then put the built-in electric heating rod in, and restore it after sticking. Tighten the bolts.

2. First put the water tank on the assembled bracket bucket holder, connect the water tank and bucket holder with bolts, and tighten the connecting nut between the shelf and bucket holder, so that the distance between the two ends of the water tank and the left and right ends of the bracket is equal, and the center line of the vacuum tube is the same as the front bracket. The planes are parallel, and then put the silicone sealing ring into the flange hole of the inner barrel and lay it flat.

To install the vacuum tube:

1. The installation of the pipe seat. Install the vacuum tube base first, the lower part of the collector tube should be installed, and the tube base should be installed at the designated position of the bracket.

2. Intubation. First check the sealing silicone ring sleeved in the inner tank of the thermal insulation layer, then check whether the tail angle of the vacuum tube process is damaged, then check the transparency of the coating like mercury, and check whether the nozzle has processing burrs and roundness. Escape the outer sealing rubber ring of the vacuum tube into the vacuum tube for about 15cm, fully wet the mouth of the tube with soapy water, and hold the end of the vacuum tube with your right hand. One is to protect the tail angle of the process, and the other is to facilitate the intubation. Insert the vacuum tube in the direction of the vertical nozzle, push it into the water tank by force evenly and lightly, and return it to the tube seat after insertion, so that all the vacuum tubes are installed in sequence.

Connect the hot and cold water pipes:

1. Wrap the tape around the water inlet and outlet, and then install the pipe fittings to link the solar energy special pipeline;

2. The electric heating cable is closely attached to the outer wall of the pipe and fastened with adhesive ties;

3. Install the sensor in the water level gauge hole of the water tank mall, and use thick polyethylene rubber-plastic pipe for insulation on the outside of the pipe;

4. The water on the solar water tank is connected by tap water.

wiring:

1. Electric heating wiring. The red wire is the live wire, the two-color wire is the ground wire, and the other one is the zero wire. Peel the skin to expose about 2cm of copper wire, and cover it with heat shrinkable tubing for insulation and dust prevention. Then connect the power cord to the three wires in color, connect them firmly, and wrap them uniformly with waterproof insulating tape from the outside to avoid short circuits.

2. Electric heating cable wiring. Cut a bevel on the port of the electric heating cable, so that the distance between the two wires is relatively far away, so as to avoid the short circuit of the link. Wrap it with insulating tape to make it fully insulated, align the end of the electric heating cable with the end of the pipe, and fix it on the official road with insulating tape to make it close to the pipe wall. The other end is the terminal of the intelligent controller. If there is a booster water pump, the connection of the water pump is connected in parallel with the electric heat tracing.

Solar water heater installation precautions

1. The pipeline design should be asked clearly

A series of questions such as which valve is used for and why the pipeline is designed in this way must be asked clearly. Make sure that the hot and cold water does not run through the pipes. Because some cold water pipes cannot enter hot water, generally adding a check valve can solve this problem. In addition, a main valve must be added to the inlet and outlet of cold and hot water, otherwise it will be very troublesome to maintain. The design of the pipeline should save space as much as possible.

2. Outdoor pipeline insulation

The poor insulation effect of outdoor pipelines will cause the pipelines to freeze and crack. Nowadays, many people use electric cables to prevent the outdoor pipelines from being frozen and cracked. In winter, the power supply can ensure that the pipelines are not frozen, but the disadvantage of this method is that it costs electricity. In fact, an intelligent control system can be added to only power on when needed, rather than long-term.

3. Roof installation direction

When the solar water heater is installed on the roof, it must be in the south direction. It is best that there are no tall trees, buildings and other obstructions within 120° of the front to prevent the sun from being blocked. In addition, thermal insulation should be considered when designing pipelines and to avoid long outdoor water pipelines.

4. Fixing the water heater

The main unit of the water heater is generally installed on the roof or other high places, so the fixation of the water heater is a very critical step. It must be strictly operated, and the fixation must be checked regularly to prevent accidents.

5. Avoid sun exposure

After the installation is completed, the first water supply must be in the morning or evening to prevent the vacuum tube from being very hot due to air drying. In this case, sudden cold water will cause "explosion of the tube". The water in the water tank should be kept in a certain amount to avoid empty sun, which will affect the life of the glass solar water heater pipeline.