Dynamic thermostatic radiator valves DYNAMICAL

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1 ynamic thermostatic radiator valves YNMIL series RIT ISO 9 M 6 /7 G unction The YNMIL valve allows the automatic dynamic balancing and pressure-independent adjustment of the thermal medium in the radiators of two-pipe heating systems. The device, in conjunction with a thermostatic, electronic or thermoelectric control, combines different functions in a single component. The use of dynamic thermostatic valves in combination with thermostatic control heads makes it possible to keep the ambient temperature automatically constant, at the set value, in the room where they are installed, thus guaranteeing effective energy saving. Reference documentation Tech. broch. 9 Thermostatic control Series Tech. broch. Thermo-electric actuator 66. series. Tech. broch. Thermostatic control series. Tech. broch. 6 lectronic thermal control system Series Product range VLVS: or steel pipes: series ynamic thermostatic radiator valve, angled version sizes /8, / and / (*) series ynamic thermostatic radiator valve, straight version sizes /8, / and / (*) series ynamic thermostatic radiator valve, reverse-angled version sizes /8, / or copper, simple plastic and multi-layer pipes: series ynamic thermostatic radiator valve, angled version sizes /8, / radiator x p., piping series ynamic thermostatic radiator valve, straight version sizes /8, / radiator x p., piping 7 series ynamic thermostatic radiator valve, reverse-angled version sizes /8, / radiator x p., piping THRMOSTTI ONTROL HS N THRMO-LTRI TUTORS: ode Thermostatic control head with built-in sensor with liquid-filled element adjustment scale corresponding to 7 8 ode Thermostatic control head with remote sensor liquid-filled element adjustment scale corresponding to 7 8 series Thermostatic control head with built-in sensor with liquid-filled element adjustment scale corresponding to 7 8 series Thermostatic control head with remote sensor liquid-filled element adjustment scale corresponding to 7 8 series Thermostatic control head with built-in sensor with temperature indicator adjustment scale corresponding to series Thermo-electric actuator * / with tailpiece without rubber seals Technical specifications of valves Material ody: brass N 6 W67N, chrome plated Obturator control stem: stainless steel Hydraulic seals: PM ontrol knob: S (PNTON 6) Performance Medium: water, glycol solutions Max percentage of glycol: % Max differential pressure with control fitted. bar Maximum working pressure: bar Nominal p control range: (reg. -) kpa (reg. -6) kpa low rate regulation range: l/h Thermal medium working temperature range: 9 actory pre-setting: position 6 Technical specifications of /// series thermostatic control heads djustment scale: d djustment temperature range: 7 8 rost protection cut-in: 7 Max. ambient temperature: Length of capillary pipe series and code 99: m Room temperature indicator series: 6 6 djustment range of//// series thermostatic control heads Technical specifications of 66. series thermo-electric actuators Normally closed lectric supply: Power consumption: Protection class: lectric supply cable: V (ac) or V (ac)/(dc) W IP (in vertical position) 8 cm

2 imensions G% ode /8" /" /" /8" /" /" ode /8" /" /" /8" /" /" ode + /8" p., /" p., 8.. ode + /8" p., /" p., 8. 6 ode + + /8" /" /8" /" ode 7 + /8" p., 8 % /" p., alancing of systems G% G% The hydronic circuits serving air conditioning systems must be balanced, meaning that they must be constructed in such a way as to guarantee the design flow rates of the thermal medium. epending on the type of system and the appliances installed, and also on the type of control to be implemented, specific balancing devices are required. Static balancing Static-type devices are conventional devices suitable for use in constant flow rate circuits or circuits subject to limited load variations. With static-type devices, the circuits are difficult to balance perfectly and have operating limitations in the case of partial closure by means of the regulating valves. The flow rate in the open circuits does not remain constant at the nominal value. G% G% ynamic balancing ynamic devices are modern automatic devices, mainly suitable for variable flow rate systems % with thermal loads that % change frequently. They can balance the hydraulic system automatically, ensuring each terminal receives the % design flow rate. ven in the case of partial circuit closure by means of the regulating valves, the flow rates in the open circuits remain constant at the nominal value. % G% This behaviour is maintained even if there is modulation of the loads; the flow rate value remains constant at the value corresponding to each partial load. G% G% G% G% % Total load Partial load Total load Partial load %

3 Operating principle The dynamic thermostatic valve has been designed with the purpose of controlling a flow rate of thermal medium in the radiators of two-pipe heating systems that is: adjustable in accordance with the requirements of the part of the circuit controlled by the device; constant despite any variation in differential pressure conditions in the circuit. The device, in conjunction with a thermostatic control head, combines different functions in a single component:. ifferential pressure regulator, which automatically cancels the effect of the pressure fluctuations typical of variable flow rate systems and prevents noisy operation.. evice for pre-setting flow rate, which allows direct setting of the maximum flow rate value, thanks to the combination with the differential pressure regulator.. low rate control depending on the ambient temperature, thanks to the combination with a thermostatic control head. The flow rate control is optimised because it is pressure-independent. evice () regulates the p and keeps it constant across the device (+), by means of an automatic action (balancing between the force generated by the differential pressure and the internal opposing spring). If (p -p ) increases, the internal p regulator reacts to close the bore and maintains p constant; in these conditions the flow rate will remain constant. evice () regulates flow rate G by changing its bore cross section. The change in bore cross section determines the hydraulic coefficient value (Kv) of the regulator device (), which remains constantly at: - a manually pre-set value - a value determined by the actuator's regulating action. Working range or the device to keep the flow rate constant independently from the circuit's differential pressure conditions, the total valve p (p-p) must be in the range between the minimum p value ( kpa for adjustments from to and kpa for adjustments and 6) and the maximum value of kpa. low rate [l/h] 6 8 p p p p constant 6 Where: p = upstream pressure p = intermediate pressure p = downstream pressure (p - p ) = total valve p (p - p ) = constant p kpa kpa (*) kpa Δp minimum Working range Δp (kpa) (*) Recommended working range: for the best dynamic behaviour without problems linked to the passage of the water flow through the valve it is recommended to work with p < 7 kpa. Δp min ( 8 l/h): kpa Δp min (- l/h): kpa low rate accuracy + G (m /h) G G 8 G [%] G 6 p G Δp Δp (kpa) minimum kpa kpa kpa Working range G [l/h] p p Δp min ( 8 l/h): kpa Δp min ( l/h): kpa

4 onstruction details ompact device The dynamic valve has been designed with dimensions compatible with those of traditional valves, therefore in case of requalification, no special adaptations are required. IMPORTNT! The dynamic valve headwork cannot be installed in a traditional valve. Headwork replacement The headwork, preassembled in a single body, contains all the regulating components. It can be inspected for cleaning or replacement if necessary using the special headwork replacement kit (code 87), without any need to remove the radiator valve from the pipe. Valve The stainless steel control stem () has a double PM O-Ring seal. The PM obturator () is made so as to optimise the hydraulic characteristics of the valve during the progressive action of opening or closing in thermostatic operation. The internal pre-setting device () is made of anti-seizing polymer. The balancing membrane () made of PM with high mechanical sensitivity combined with the spring and with the control device allows adjustment of the differential pressure. There is a protective casing () to minimise the risk of dirt getting into the dynamic component. ase of design The presence of the internal device which is able to regulate the flow rate and stabilise the working p allows faster design and balancing operations: no support components are required for calculations and pre-setting is very simple. Hydraulic characteristics Without thermostatic control head With thermostatic control head and K proportional band 6 G Num. - Maximum flow rate [l/h] 8 6 G K - low rate (K) [l/h] p [kpa] 6 8 p [kpa] G Num. (l/h) G K (l/h) Pre-setting position System sizing or correct system sizing, the valves are normally selected by determining the pre-setting value based on the design flow rate on the diagram with thermostatic control head and K proportional band. Stepped adjustement, not continuos.

5 xample of pre-setting using angled / dynamic thermostatic valves Let us suppose we have to balance three circuits having the following characteristics: esign power ircuit Q = 8 kcal/h ircuit Q = 7 kcal/h ircuit Q = 6 kcal/h esign temperature difference T = esign flow rate The design flow rate for each radiator is calculated with the equation: ircuit ircuit ircuit G = Q/T G = 9 l/h G = 7, l/h G = 8 l/h Pre-setting and effective flow rate The setting positions can be easily determined based on the design flow rates from the graph or from the table shown in the paragraph "Hydraulic characteristics" (considering K adjustment for sizing). ircuit pos. 6 G = 9 l/h ircuit pos. G = l/h ircuit pos. G = 8 l/h Maximum flow rate p [kpa] Minimum operating p: on site check of the disadvantaged circuit The dynamic thermostatic valve, with K adjustment, works between kpa and kpa. or this reason it is necessary to identify the most disadvantaged circuit and determine the available p using the p measuring kit code. (See accessories) and ensure the minimum operating p to this circuit, adjusting the circulation pump head. Minimum operating p: calculation of disadvantaged circuit The most disadvantaged circuit, to which ensure the minimum operating p can be identified through the rigorous calculation of the head losses. - alculation of the head losses of every single radiator circuit (p ) p = p min + p T/R where: p min minimum working p of the YNMIL valve p T/R head losses in the pipes / radiator. (*) onsequently: ircuit ircuit ircuit p min kpa kpa kpa p T/R (*), kpa kpa kpa p, kpa kpa kpa - alculation of the head losses of the connecting sections (p T ). (*) Section - Section - Section - p T kpa kpa, kpa (*) In the case in the example, for the sake of simplicity the values are assumed to be known without giving the whole calculation. - alculation of the total head losses of each circuit with respect to the circulator. (p TOT ). irc. p TOT = p T - + p = +, = 6, kpa irc. p TOT = p T - + p T - + p = + + = 9 kpa irc. p TOT = p T - + p T - + p T - + p = + +, + = 9, kpa In the case in the exampled, the most disadvantaged circuit is number, which corresponds to the maximum total head loss. etermining the circulation pump flow rate The flow rate of the circulation pump is calculated, with sufficient accuracy, as the sum of the G max flow rates of the radiators (a). Therefore: G pump = S G max In a theoretically more accurate way, the flow rate can also be calculated as the sum of the flow rates at which the YNMIL valves are set (b). In the previous example: (a) S G max = 7, l/h (b) pos.6 + pos. + pos. = = l/h the differences involved between the two methods are not very high. etermining the circulation pump head The head of the circulation pump is calculated as the sum of the head losses of the most disadvantaged circuit. p isadvantaged (including the working p min of the YNMIL valve and the pipe/radiator losses p T/R ) and the p of the sections connecting that circuit to the circulation pump. Therefore: p pump = p min +p T/R disadvantaged + S p connecting sections In the case in the example: p pump = p TOT Δp min Δp T/R Δp min Δp T/R Δp min Δp T/R G Δp G Δp G Δp G Tot. ΔP TOT G + G G ΔP T - ΔP T - ΔP T -

6 Pre-setting and installation of thermostatic heads, electronic or thermo-electric actuators Remove the knob from the valve. Installation of valves with thermostatic control heads The thermostatic control heads must be installed in horizontal position. To pre-set the flow rate, position the appropriate shaped nut. The reference of the setting position is defined by the orientation of the flat side surface () of the control stem. The sensitive element of the thermostatic control heads must never be installed in niches, radiator cabinets, behind curtains or exposed to direct sunlight, otherwise it may produce false readings. Rotate the control stem to select the desired position. Remove the adjustment nut. Operating principle of thermostatic control head Valve closed Install the thermostatic (), electronic () or thermo-electric () actuators on the valve. The control device of the thermostatic valve is a proportional temperature regulator, composed of a bellows containing a specific thermostatic liquid. s the temperature increases, the liquid increases in volume and causes the bellows to expand. s the temperature decreases, the inverse process occurs; the bellows contracts due to the thrust of the counter-spring. The axial movements of the sensor element are transmitted to the valve actuator by means of the connecting stem, thereby adjusting the flow of medium in the heat emitter. Valve open ombination with heat metering systems The thermostatic valves can be used in combination with metering systems. In this way, the actual consumption of each radiator can be monitored in order to contain system running costs which, in centralised systems, can be shared in such a way to be advantageous to the end users.

7 pplication diagrams System with risers with dynamic thermostatic valves and thermostatic control heads. Independent zone system with dynamic thermostatic valves with thermostatic control heads and variable speed circulator

8 NTR T HOL S LR UNIT ZRO UTO/O RL ccessories Kit for measuring Δp in the circuits with dynamic valves. ode To use the instrument, the headwork replacement kit is necessary (code 87), which allows you to extract the headwork of the dynamic thermostatic radiator valve and to insert the appropriate headwork for the measuring instrument. SPIITION SUMMRIS series ynamic thermostatic radiator valve fitted for thermostatic control heads, electronic and thermo-electric actuators. ngled connections for steel pipe. onnection to the radiator /8 or / M with tailpiece supplied with PM seal, / with tailpiece without seal. rass body. hrome plated. Knob in S green PNTON 6, for manual control. Stainless steel control stem. ouble seal on control stem with PM O-Ring. Medium working temperature range 9. Maximum working pressure bar. PT - INTRNTIONL PPLITION PNING. series ynamic thermostatic radiator valve fitted for thermostatic control heads, electronic and thermo-electric actuators. Straight connections for steel pipe. onnection to the radiator /8 or / M with tailpiece supplied with PM seal, / with tailpiece without seal. rass body. hrome plated. Green PNTON 6 S knob for manual control. Stainless steel control stem. ouble seal on control stem with PM O-Ring. Medium working temperature range 9. Maximum working pressure bar. PT - INTRNTIONL PPLITION PNING. series ynamic thermostatic radiator valve fitted for thermostatic control heads, electronic and thermo-electric actuators. ngled connections for copper, plastic and multilayer pipes p., for pipes from to 8 mm. onnection to radiator /8 and / M with tailpiece equipped with PM seal. rass body. hrome plated. Knob in S green PNTON 6, for manual control. Stainless steel control stem. ouble seal on control stem with PM O-Ring. Medium working temperature range 9. Maximum working pressure bar. PT - INTRNTIONL PPLITION PNING. series ynamic thermostatic radiator valve fitted for thermostatic control heads, electronic and thermo-electric actuators. Straight connections for copper, plastic and multilayer pipes p., for pipes from to 8 mm. onnection to radiator /8 and / M with tailpiece equipped with PM seal. rass body. hrome plated. Knob in S green PNTON 6, for manual control. Stainless steel control stem. ouble seal on control stem with PM O-Ring. Medium working temperature range 9. Maximum working pressure bar. PT - INTRNTIONL PPLITION PNING. series Reverse-angled dynamic thermostatic radiator valve fitted for thermostatic control heads, electronic and thermo-electric actuators. or steel pipes. onnection to radiator /8 and / M with tailpiece equipped with PM seal. rass body. hrome plated. Knob in S green PNTON 6, for manual control. Stainless steel control stem. ouble seal on control stem with PM O-Ring. Medium working temperature range 9. Maximum working pressure bar. PT - INTRNTIONL PPLITION PNING. 7 series Reverse-angled dynamic thermostatic radiator valve fitted for thermostatic control heads, electronic and thermo-electric actuators. or copper, simple plastic and multilayer pipes p., for pipes from to 8 mm. onnection to radiator /8 and / M with tailpiece equipped with PM seal. rass body. hrome plated. Knob in S green PNTON 6, for manual control. Stainless steel control stem. ouble seal on control stem with PM O-Ring. Medium working temperature range 9. Maximum working pressure bar. PT - INTRNTIONL PPLITION PNING. We reserve the right to make changes and improvements to the products and related data in this publication, at any time and without prior notice. aleffi S.p.. S.R. 9 n. 8 ontaneto d gogna (NO) Italy Tel ax info@caleffi.com opyright 7 aleffi