Components for solar heating systems

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1 solarorkli Components for solar heating systems Components for heating and plumbing Components for solar heating systems Manifolds and distribution equipment Thermostatic valves Manual valves Motorised zone valves Mixing valves Climate control Safety groups and valves Home systems components Gas valves Pipe conection solutions

2 Orkli has produced components for heating, water heating, and for domestic appliances since Products are distributed to all five continents, with a network of its own offices in over 20 countries. Its continuous heavy investment strategy, with an average of around 12 million euros invested per year, means that it not only incorporates new products to its extensive catalogue year after year, but also embarks on new activities such as the Lurbero Underfloor Heating system (two years ago) and the recent new activity, SolarOrkli, with components for solar heating systems. Remaining at the leading edge requires major development and investment in R+D, and Orkli includes this challenge within its strategy, combining with our corporate objectives of innovation in our products, and progressive business management. Orkli is a company belonging to the Mondragón Corporación Cooperativa, within which it forms part of the Mondragón Components Division. This business group accounts for over 85,000 jobs and it groups together more than 220 companies and organisations, structured into sectorial groups. It also has technological backing from large research and development centres such as Ikerlan, Ceit and Robotiker, as part of a process of constant knowledge updating, and it favours a philosophy of innovation to assure new paths for the future.

3 Components for solar heating systems Solar heating installations are normally used to heat water for domestic use or for heating

4 Components for solar heating systems SOLAR HEATING INSTALLATIONS Solar heating systems basically consist of the following: a. Solar collector. b. Accumulator. c. Hydraulic components. d. Regulation. e. Support system. Support system Boiler Regulator Solar Collector Accumulator Mixing Valve a. Solar collector The solar collector is the element that converts the energy from solar radiation into usable heat, by heating up the fluid that circulates through it. There are several types of collectors; the most common type are flat solar collectors. Cover Absorbent surface Rear insulator

5 b. Accumulators Solar radiation does not usually coincide with the actual consumption of domestic hot water or heating, and the energy provided by the sun must therefore be retained for later consumption. The energy is stored by increasing the temperature of the water contained in the accumulator. Solar accumulators are normally equipped with an integrated heat exchanger which transfers the energy captured by the collectors into water for consumption. In large installations, the heat exchanger is normally a separate element, as a large heat exchanging surface cannot be contained in the accumulator. Insulating material Internal heat exchanger c. Hydraulic components A solar heating installation is a hydraulic circuit, and it must therefore include a series of components for both correct functioning and safety purposes. As a component manufacturer, Orkli provides a wide range of valves and accessories for creating a solar heating system. d. Regulation The regulation system controls the pump and the motorised valves in order to achieve correct energy transmission from the panels to the fluid to be heated. It decides when the pump should work and the position of the valves according to the temperatures at various points on the circuit, generally the collectors and the accumulator. e. Support system This assures the user receives heating and hot water on days when there is insufficient solar radiation to satisfy the demand.

6 Components for solar heating systems HYDRAULIC COMPONENT SELECTION A solar heating installation is made with two separate circuits: Primary circuit: this circuit conveys the heat captured by the collectors to the heat exchanger. Secondary circuit: this circuit conveys the water heated by the primary circuit to the tap for consumption. The primary circuit is the circuit which has the greatest differences with respect to a conventional heating or domestic hot water installation. Temperature: the design of solar collectors is optimised to enable the greatest possible amount of energy to be conveyed to the primary circuit, and they can therefore reach very hot temperatures. As general criteria for component selection, the following may be taken into account: a. Flow branch: this is the branch that conveys the fluid heated at the panels to the heat exchanger. The elements installed in this branch must be able to withstand a continuous temperature of at least 150ºC: ball valves, air separators, non-return valves, zone valves, etc. b. Return branch: when the heat collected has been transferred inside the heat exchanger, the temperature of the fluid drops, and the temperatures this branch needs to withstand are less extreme: continuous temperatures of 100ºC (pump, flow regulator, ball valves, non-return valves, etc.). Fluid: The generator (collector) must be located outdoors in order to collect solar radiation. This means precautions must also be taken to prevent the fluid in the circuit from freezing when the outdoor temperature drops below 0ºC. In regions where this could happen, a mix of water and anti-freeze (ethylene glycol) is used as a fluid. The components installed in this circuit must therefore be designed for working with these types of fluids. Pressure: the standard pressures these installations work at are similar to those of heating circuits (1.5-2 bar). However, in extreme cases the temperature may cause the pressure to increase, and so the components should be able to withstand pressures of up to 8 bars.

7 SOLARORKLI COMPONENTS FOR SOLAR HEATING INSTALLATIONS Vent valve Solar collector Regulator Expansion vessel Hydraulic Solar Unit Support system boiler Zone valve Accumulator Valve with air separator Mixing valve

8 Components for solar heating systems HYDRAULIC SOLAR UNIT The hydraulic unit for solar heating installations is a group of components with all the necessary hydraulic elements in the primary circuit of these installations. TECHNICAL CHARACTERISTICS The main characteristics that distinguish these components from those used in heating and domestic hot water systems is that they can be subjected to very high temperatures. They are therefore made of materials especially selected for working at these temperatures: Maximum working temperature in flow branch: 160ºC. Maximum working temperature in return branch: 120ºC. Maximum working temperature of safety valve: 160ºC. Maximum permissible pressure: 10 bar. Safety valve calibration: 6 bar Thermometer temperature range: 0-120ºC. Flow indication range: 2-14l/min. Manometer scale: 0-10bar. Expanded polypropylene density: 50gr/l

9 Components and functions: 1: Solar pump. 2: Shut-off valves with non-return valve and integrated thermometers (in the flow and return branch, to prevent reverse flows). 3: Safety unit consisting of: a-solar safety valve calibrated to 6 bar. b-manometer (0-10 bar). c- connection for expansion vessel. 4: Flow meter and flow regulator. The purpose of this element is to balance the primary circuit according to the number of collectors, as the collectors have an optimum working flow (approx 1 litre per minute and m 2 of collector). 5: Air vent chamber. Automatic air vents are installed in the collectors, but these must be closed to prevent the steam from coming out of the vents when the temperature rises to above 100ºC and the installation being emptied. 3.Safety unit 6.Filling/emptying taps 2.Shut-off valves with non-return valve 1.Solar pump 5.Air vent chamber. 6.Filling/emptying taps 4.Flow meter and flow regulator 7.Insulating casing A vent chamber is installed so that the air can be purged from an accessible area. The fluid with air flows through the inner pipe and on expansion the bubbles separate and accumulate in the upper part of the chamber. The chamber has a manual vent so that the air accumulated is periodically evacuated. 6: Filling/emptying taps. 7: Expanded polypropylene (EPP) insulating casing.

10 Components for solar heating systems HYDRAULIC CHARACTERISTICS [m] 6,4 Head 6 5,6 5,2 4,8 4,4 4 3,6 3,2 2,8 2,4 2 1,6 1,2 0,8 0,4 eco max 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 1,1 [l/s] DIMENSIONS Height of unit: 455mm. Width of unit: 235mm. Connections: 3/4 H. Distance between branches: 95mm. INSTALLATION AND START-UP Pipe connection The joints with the hydraulic unit must be made using the corresponding connectors before fixing the pipe in place, to prevent damage to the EPP casing. Wall-mounting the Hydraulic Unit Make holes in the wall for the rawl plugs at the distances indicated. 2. Place the fixing plate in the position indicated, and screw the screws into the holes. Note: make sure the visible elements coincide with the holes in the hydraulic unit cover.

11 Filling the installation 1. Open the automatic bleed valves on the solar collectors. 2. Disable the ball valve non-return valves by turning the lever 45º. 3. Gradually fill the installation with the water-glycol mixture from the lowest filling tap in the circuit, using a pump. If there are no other taps apart from the hydraulic unit taps, use the flow meter tap. 4. Close the automatic air bleed valves. Note: the pump should left running for at least half an hour so that the air bleed is complete before the bleed valves are isolated. Flow regulation 1. Check the nominal flow recommended by the panel manufacturer (approximate value 1 litre per minute and m 2 ) and calculate the flow required for your installation. 2. Completely open all the circuit valves. 3. Start up the pump at speed 1 and check if the flow indicated on the flow meter is higher or lower than required: a. If it is lower increase the speed and check it again (step 3). b. If it is higher calibrate the flow at the regulator, using a screwdriver. Adjust the step until the flow meter indicates the required flow.

12 Components for solar heating systems AUTOMATIC SOLAR VENT VALVE Description The purpose of automatic vent valves is to bleed the air from the solar heating circuit during filling and maintenance operations. In solar heating installations, automatic air vent valves must always have a shut-off valve at the front to isolate them when the installation has been filled. This prevents the fluid in the circuit from being drained by the automatic bleed valve when the temperature causes it to rise to evaporation point. Installation and start-up The air vent valves must be installed at the highest point of the installation (normally the solar collector outlet), and always in vertical position. After filling and draining the installation, close the shut-off valve installed before the air vent valve. Air vent valve with ball valve Technical characteristics Maximum working temperature: 150ºC. Fluid: 50% water-glycol mixture. Maximum working pressure: 6 bar. Connection: 3/8 M. Shut-off valve connections: 3/8 H-3/8 M. Solar collector AIR SEPARATOR Description As its name indicates, this element helps to separate the air contained in the circuit, by means of an expansion volume and a grille inside it. This air may be vented from the system by installing an automatic air vent valve at the top or via a manual vent valve. Technical characteristics Maximum working temperature: 150ºC. Fluid: 50% water-glycol mixture. Maximum working pressure: 6 bar. Upper connection: 3/8 H. Accessories for connection to Ø22mm pipe.

13 Installation The air separators must be installed on horizontal piping lines and in the horizontal position, so that the air accumulates in their upper part. The separator also includes wall-mounting accessories. Accumulator Air vent valve with air separator SAFETY VALVES Description The purpose of solar safety valves with solar membranes is to limit the pressure in the primary circuit of solar heating systems. They also include a lever for manual draining. Installation Safety valves must be installed in vertical or horizontal position, and never inverted (with the lever facing downwards). No elements isolating the valve from the rest of the system are to be installed. Technical characteristics Maximum working temperature: 160ºC. Fluid: 50% water-glycol mixture. Connections: H- H. Ethylene-propylene seal and membrane. Special stamped brass valve body, in accordance with EN standards. Spring with antioxidant treatment. Calibration pressures: 3, 4, 6, 8, 10 bar. Certification for solar safety valves: TÜV SV SOL 50 p. It is also recommendable to provide for a fluid collection device at the outlet, to catch any drips of water and anti-freeze mixture. Racord Spring Handle Sealing joint Membrane Valve part

14 Components for solar heating systems ZONE VALVES Description Motorised solar zone valves are designed to work as all-or-none regulators and as flow deflector valves in solar heating system primary circuits. 2-way valves are models normally closed at A (no voltage). When voltage is supplied to the motor the valve opens and the micro switch closes (if there is one). 3-way valves are deflector valves, with inlet at AB and outlets at A and B, and with path A normally closed (no voltage). When voltage is supplied to the motor, path A opens, path B closes and the micro switch closes (if there is one). A B A B AB There are also removable models which enable the hydraulic connection of the valve part to be made without the motorised part needing to be assembled. In the same way, when the installation is running, the motorised part can be replaced without needing to drain or work on the installation. Technical characteristics Minimum fluid temperature: -20ºC. Maximum fluid temperature: 160ºC. Fluid: 50% water-glycol mixture. Maximum ambient temperature: 50ºC. Maximum static pressure: 10 bar. Maximum differential pressure: Opening time: 12 s. Closing time: 5 s. Supply voltage: 230V (24V also available). Consumption: 6 W. Cable length: 60 cm (other lengths available to order). Complies with European Directives 89/336/EEC and 73/23/EEC. 2 way 3 way DN 15 (1/2 ) 1,4 bar 1,4 bar DN 20 (3/4 ) 0,6 bar 0,7 bar DN 25 (1 ) 0,4 bar 0,6 bar

15 Hydraulic characteristics Non-removable model. Removable model Differential pressure a.c. Flow l/h 2 way 1/2 3 way 1/2 2 way 3/4 3 way 3/4 2 way 1 3 way Installation and start-up The motorised part must never be installed below the valve part, to prevent any condensation in the connection pipes from entering the motor. The blue and brown cables supply the motor. The brown and orange cables are the micro switch cables (on models with a micro switch). Without micro switch With micro switch Blue Brown A/V Motor Blue Brown Grey Orange A/V Motor Micro N.A.

16 Components for solar heating systems Start-up Before filling the installation, the manual valve drive must be placed in manual position (MAN). After filling, and during normal valve functioning, it must be in automatic position (AUTO). The 2-way valves open. The 3-way valves divert the flow entering via AB through either A or B. On removable models, it automatically goes from manual to automatic position on start-up of the electrical installation. Auto When there is no electrical supply, and during filling, draining or emptying of the installation, the valve can work in manual position (MAN), with the following result: Man Central solar circuit Zone valve Individual solar storage heater B A Mixing valve Zone valve Individual solar storage heater B A Mixing valve

17 SAFETY UNIT Descripción Safety units are components used in domestic hot water installations for protecting hot water accumulators. The models for solar heating installations are specifically designed for use in thermo-syphon water heaters where the accumulator, and therefore the safety unit, are installed outdoors. Non-return valve Connection to accumulator Cold water inlet Non-return valve control opening DN20 Isolation valve Safety and manual emptying valve Emptying and outlet hole Safety units are made up of different components, with the following functions: Safety: to prevent the water pressure in the accumulators from reaching dangerous values. Anti-pollution: to prevent the hot water returning to the cold water supply network and contaminating the water in the water heater with discharge water. Isolation: to isolate the supply network and allow maintenance and control of the accumulator and the installation. Technical characteristics Special stamped brass body, Cu Zn 40 Pb2, EN EPDM safety valve closure gasket. PPS non-return valve. Safety valve shaft material: stainless steel. External elements resistant to UV radiation. Nominal pressure of safety valve regulation: 7 bar Safety valve closing pressure For cold water: > 6.3 bar. For steam: > 5.25 bar Non-return valve opening pressure: < 0.2 bar. Non-return valve seal pressure: > 0.03 bar. Safety units are certified in accordance with European Standard EN 1487 by the CSTB and BELGAQUA Institutes. Thermo-syphon unit accumulator Dielectric insulation connector Safety unit DN20 NF EN 1487 Cold water inlet

18 Components for solar heating systems THERMOSTATIC MIXING VALVES Description Mixing valves are mainly used in domestic hot water distribution systems to limit the temperature of the water for consumption. The temperature control is assured by quick reaction wax technology. Thermostatic mixing valves are used in solar heating installations, at the solar accumulator outlet. The main purpose of installing these valves to prevent a risk of burns to the final user when the temperature in the accumulator exceeds the maximum temperature recommended for domestic use (in solar accumulators the water can reach temperatures of over 80ºC). Specific solar heating models exist where there is a risk of the accumulator temperature exceeding 90ºC (in systems where there is no temperature limitation in the accumulator). Technical characteristics Standard model Solar model High-temperature solar model Supplied with temperature already set 41ºC 47,5 ºC 63 ºC Outlet temperature range 35 ºC 50ºC 40ºC 50 ºC 50ºC 70 ºC Hot water inlet temperature 95 ºC máx ºC ºC Cold water inlet temperature 5-25 ºC 5-30 ºC 5-30 ºC Minimum temperature difference for mix 10 ºC 15 ºC 15 ºC Temperature stability (nominal) ± 3 ºC ± 3 ºC ± 3 ºC Static working pressure 10 bar 10 bar 10 bar Installation and temperature adjustment Fit the non-return valves on the two valve inlets (on models supplied with these). Observe the flow direction indicated. Check that the hot and cold water pipes are installed at the corresponding inlets: H or a red dot for the hot water inlet, and C or a blue dot for the cold water inle. Install the filters supplied on the pipe inlet connections (on models with filters). After installing the valve, adjust the outlet temperature. Mixing valves have a special valve for preventing accidental adjustment. 1. Remove the cover. 2. Adjust the temperature by turning the valve cartridge with the special key supplied. Turn it clockwise to reduce the temperature, and anti-clockwise to increase the temperature. 3. When the desired temperature is obtained at the outlet, cut off the water supply 3 times, alternating between the hot and cold water supplies. The piston will thus travel the whole of its run and correct functioning can be assured. 4. Replace the cover.

19 REGULATION Correct use of the regulation unit is essential for optimum performance of a forced circulation system. Systems with two outlets and one relay inlet In single installations; with solar power intake for the domestic hot water and one single heat exchanger, there are two main functions: 1. Start-up and stopping by T between the collectors and accumulator. A temperature difference (usually 7ºC) is determined for the pump to start working, and another difference (2ºC) for it to stop. 2. Temperature limitation in the accumulator. Although the temperature setting may be approximately 60ºC, on days with high solar radiation it is preferable to increase the water temperature in the accumulator to prevent overheating at the panels. Solar Collector Accumulator Systems with two relay outlets For more complex installations where several pumps or motorised valves need to run, a regulation system with more relay outlets is used. The most common functions are: a) Working a zone valve to divert the flow when the desired temperature is reached in the accumulator. b) Diverting the flow to the second heat exchanger in dual coil storage heaters to improve stratification or with two accumulators c) Using two pumps in installations with an external heat exchanger. Solar Collector Solar collector Regulator Regulator Accumulator Accumulator

20 Orkli Italia SRL Cassina Plaza Scala 3 Via Roma 108 I Cassina de Pecchi (MI) Tel.: Fax: rpiccardi@mccit.com Orkli, S. Coop. Ctra. Zaldibia, s/n E Ordizia (Gipuzkoa) Tel.: Tel. int.: Fax: solarorkli@orkli.es