Plumbing Africa March 2020 | Page 65

PRODUCTS On reaching the set temperature, the obturator (1), governed by the thermostatic sensor (2), modulates the closure of the hot water outlet (3), thereby aiding circulation towards the other connected circuits. If the temperature decreases, there is the opposite action and the passage reopens, so as to ensure that all the branches of the system reach the required temperature. 63 PRODUCTS 63 The adjustment strainer can be removed from the valve body for checking, cleaning or replacement. Temperature adjustment The temperature is set at the desired value by turning the upper screw with the special knob. System sizing The thermostatic regulators are used for automatic balancing of the various branches of domestic hot water recirculation circuits, so as to ensure the required temperature in each section and limit heat dispersion. The recirculation circuits are generally sized according to the flow rate required for each branch, based on the allowed heat dispersion and the corresponding decrease in temperature along the pipe. Generally speaking, the maximum allowed temperature drop between the point of departure from the central system and the point of return to the latter is 5°C. According to the flow rate, determined using the various calculation methods, it is possible to calculate the head loss caused by passage through the thermostatic regulator, using the graphs provided below. The head loss curves are shown with valve in thermostatic operating mode. In this case, reference is made to an average aperture of 5K, between the valve set temperature and the incoming water temperature, bearing in mind the dispersion along the pipe. This value allows the head required for the recirculation pump to be limited. It is also always necessary to ensure the minimum flow rate required by the mixing valves in the central system. The suggested control range is from 55 °C to 60 °C (according to current standards). Factory setting 58 °C. Installation Before fitting the thermostatic regulator, the pipes must be flushed to ensure that none of the impurities in circulation will reduce its performance. We recommend always installing strainers of sufficient capacity at the inlet from the water main. The thermostatic regulator can be fitted in any position, vertical or horizontal, by respecting the flow direction indicated by the arrow on the valve body. The thermostatic regulator must be installed according to the diagrams given in this manual. It must be installed in such a way as to allow free access to the device, for checking operation and maintenance. The graduated scale shows the temperatures at which the indicator can be set. It is recommended to set the valve temperature at a value about 5K greater than the water temperature at the valve inlet, considering the heat losses along the line, to limit the head required at the recirculation pump. Take care to ensure the minimum flow rate at the mixing valves in the central heating system. Adjustment locking After adjusting the temperature, the setting can be locked at the desired value using the control knob. For this purpose, unscrew the locking screw at the top of the control knob, remove the knob and then put it back on so that the internal reference couples with the protrusion on the knob holder nut. When this block is used, the reference of the indication of the temperature values on the knob is lost. To restore it, completely unscrew the regulating headwork counter-clockwise. Reposition the knob on MAX value. Tighten the locking screw. Maintenance #Share your innovative and relevant products with us Send us a short description of your product with a high resolution image: [email protected] March 2020 Volume 26 I Number 01 www.plumbingafrica.co.za www.plumbingafrica.co.za