smoke pipes VERY LOW TEMPERATURE CONDENSING UNIT Low NOx Class 5 OUTPUT RANGE from 115 to 600 kw OPERATION TEMPERATURE no limit on the return temperature SUPPLY Natural Gas or LPG MODELS 150 230 300 348 400 500 600 SEASONAL EFFICIENCY A A A A A A A ENERGETIC CLASS according to Dir. 92/42/EC large water content, boiler body completely in stainless steel, with two return connections wide modulation premix burner, no circulation pump is required
Stainless steel condensing units MAIN COMPONENTS SPK 150 SPK 230-300 - 348-400 - 500-600 1 10 13 2 G 10 13 2 G Sm M 6 12 3 14 5 4 Sm M 11 3 12 3 14 5 9 4 9 7 7 R 6 R 6 11 11 8 Scond 8 Scond 1. Gas pressure switch 2. Fan 3. Door insulation 4. Combustion chamber 5. Panel Board 6. Technical water tank 7. Stainless steel vertical smoke pipes with internal aluminium 8. Condensate collection pan 9. Flue gas pressure switch 10. Ignition electrode 11. Boiler drain valve 12. Visual inspection glass 13. Gas pressure switch 14. Burner G Gas inlet M Heating system flow R Heating system return Sm Air vent connection S cond Condensate drain DN 32 TECHNICAL DATA SPK 150 230 300 348 400 500 600 NOMINAL OUTPUT at 50/30 C (in condensing mode) min. / max NOMINAL OUTPUT at 80/60 C (in conventional mode) min. / max. kw 36.6 / 146 54.6 / 226.8 70 / 292.7 99 / 360.1 97 / 399 124 / 472 135.2 / 578.2 kw 32.5 / 136.3 48.2 / 209.2 62.0 / 273.7 87.7 / 339.4 86.1 / 371.5 110 / 440.1 118.5 / 534.5 EFFICIENCY CLASS (ex DIR. 92/42/CE) HHHH HHHH HHHH HHHH HHHH HHHH HHHH EFFICIENCY AT NOM. LOAD at 50/30 C % 104.2 106 104.5 104.5 105 105 105 NOMINAL INPUT kw 140 214 280 348 380 450 550 MODULATION RATIO 1:4.0 1:4.3 1:4.3 1:3.9 1:4.2 1:3.9 1:4.4 NOx CLASS 5 5 5 5 5 5 5 WATER CONTENT l 153 210 270 340 340 340 425 MAX. PRESSURE at the CHIMNEY BASE Pa 100 100 100 100 100 100 100
Stainless steel condensing units SPK 150 600 PRODUCT PLUS VALUES MAXIMUM CERTIFIED EFFICIENCY (Dir. 92/42 CE) over 109% at the least modulated Output and up to 109% at part load MODULATION RATIO UP TO 1: 4.3 HOMOLOGATION IN OUTPUT RANGE LARGE WATER CONTENT THERMAL ELEMENT ZERO FLOW RATE UNIT (no recirculation needed) designed with internal geometries to allow a natural inner circulation. No limitation in the C.H. return temperature Recirculation pump not required THERMAL ELEMENT WITH VERTICAL DEVELOPMENT entirely in stainless steel AISI 316L, complete with premix modulating burner and safety devices SPECIAL SMOKE PIPES (Unical patent) in stainless steel with multi-fin inserts in Al/Si/Mg of high thermal conductibility, on purpose designed to improve the condensate outflow, optimizing the thermal exchange. POSSIBILITY OF MOUNTING IN CASCADE (contact Unical) CYLINDRICAL VERTICAL COMBUSTION CHAMBER without flame reversion EFFECTIVE INSULATION with mineral wool 50 mm thick EASY MAINTENANCE - pneumatic opening of the combustion chamber door - retractable platforms for easy access to the burners (std. supplied on mod. 400-500-600) SMOKES NON RETURN VALVE it reduces the sensitive heat losses and increases the operation safety ELECTRONIC PANEL BOARD HSCP + 1 SHC (std. supplied) for command and control, with proportional regulation BCM for boiler management SEASONAL EFFICIENCY +30% in comparison with the conventional boilers MODULATING PUMP (optional) directly controlled by the boiler electronics in order to assure the maximum condensation at all regimes AVAILABLE PRESSURE 100 Pa at the chimney base in order to resolve every possible configuration of smoke evacution ADDITIONAL SAFETY DEVICES KIT with safety accessories and filter on the return (optional) Kit INAIL SPK 300 500
Stainless steel condensing units DIMENSIONS SIDE VIEW FRONT VIEW SIDE VIEW H1 L P2 P P1 G Sm M H L1 L2 L3 H3 H2 H5 H4 H6 H7 H R S REAR VIEW TOP VIEW SPK Depth mm Width mm Height mm P P1 P2 L L1 L2 L3 H H1 H2 H3 H4 H5 H6 H7 Weight kg 150 944 788 156 666 120 288 81 1809 65.6 1467 323.5 743 571 1579 1679 407 230 1092 954 141 846 120 277 43 1917 65.6 1557 356 775 630 1697 1768 479 300 1181 1036 144 910 100 303 200 1946 65.6 1618 353 790 635 1741 1796 549 348 1276 1152 124 996 100 326 200 2130 65.6 1712 390 820 698 1794 1974 716 400 1276 1152 124 996 100 326 200 2130 65.6 1712 390 820 698 1794 1974 716 500 1276 1152 124 996 100 326 200 2130 65.6 1712 390 820 698 1794 1974 716 600 1398 1256 142 1096 200 388 220 2206 65.6 1753 390 810 763 1863 2052 875
Stainless steel condensing units SPK 150 600 DIMENSIONS TO INSERT THE BOILER IN THE BOILER ROOM FRONT VIEW SIDE VIEW P c H P (P1+P2) 150 Lp L BOILER DIMENSIONS WITHOUT ITS CASING [mm] Example of corridor widht (Lc) calculation required to handle the boiler SPK 150: SPK P L H 150 917 655 1785 230 1027 795 1895 300 1134 845 1910 348 1258 965 2075 400 1258 965 2075 500 1258 965 2075 600 1313 1065 2186 L Boiler Width P Boiler Depth Lc Corridor Width Lp Door Width POSITIONING IN THE BOILER ROOM CLEARANCE H8 SPK H8(*) H9 115 2109 2300 H9 150 2109 2300 500 500 1500 230 2147 2500 300 2366 2500 348 2690 3000 400 2690 3000 500 2690 3000 900 600 2770 3000 (*) Space for combustion chamber opening
Stainless steel condensing units FLUE GAS EXHAUST PIPE CONNECTION To connect the flue gas exhaust pipe, local and national standards must be observed In the event the boiler is replaced, ALWAYS replace the flue gas pipe as well. The boiler is type approved for the exhaust configurations listed below: B23P ATTENTION For this type of connection, the room follows the same installation rules for boilers with natural draught. B23P ATTENTION With C63 configurations, you must order the optional air intake kit, which contains the installation instructions. Connection to a combustion products evacuation pipe outside the room; the combustion air is taken directly from the room where the appliance is installed. Separate combustion air intake and combustion products evacuation pipes. (Commercial accessories) HEAD AVAILABLE AT THE BASE OF THE CHIMNEY HEAD AVAILABLE AT THE BASE OF THE CHIMNEY D (Drain) I (Intake) D (Drain) I (Intake) Dp = 100 Pa - The maximum permitted length of the pipes is determined by head (Dp) available at the base of the chimney. Dp = 100 Pa Dp = 40 Pa The maximum permitted length of the pipes is determined by head (Dp) available at the base of the chimney.
Stainless steel condensing units SPK 150 600 CONNECTIONS CONNECTIONS SPK G Gas Inlet inch M Flow DN R Return DN A Air intake Ø mm S Flue gas exhaust Ø mm Sm Air vent connection inch Sc Condensation drain Ø mm 150 1 65 65 150 200 (*) 1 DN 40 230 1 ¼ 65 65 250 250 1 ¼ DN 40 300 1 ¼ 80 80 250 250 1 ¼ DN 40 348 1 ½ 80 80 250 300 1 ½ DN 40 400 1 ½ 80 80 250 300 1 ½ DN 40 500 1 ½ 80 80 250 300 1 ½ DN 40 600 1 ½ 100 100 250 300 1 ½ DN 40 A (*) FLUE SOCKET ADAPTER (optional) ø200-ø150 (SPK 150) for adaption to existing chimneys Ø150 Sm G Sc Scond BOILER DRAIN CONDENSATION DRAIN M SAFETY VALVE DRAIN Provide a drain pipe with funnel and a trap that lead to a suitable drain, in correspondence with the drain. This drainage must be controlled on sight. If this precaution is not taken, triggering of the safety valve can cause damage to person, animals and object, for which the manufacturer cannot be held responsable S Scond R Sc Attention! Do not mix the heating water with incorrect concentrations of antifreeze or anti-corrosion substances! This could damage the gaskets and cause noise during operation. Unical will not be held liable for damage to persons, animals or objects due to failure to comply with the above instruction. The mains pressure must be within 0.5 and 6 bar (in the event of greater pressure install a pressure reducer). To fill the system, you must provide a filling valve on the heating circuit, or use the optional accessories. The boiler is equipped with is own draining valve, Sc. This valve can never be used to drain the system since all the dirt in the system can accumulate in the boiler and jeopardise its proper operation. Therefore, before using the drain valve, make sure the system s check valve, which is situated under the pump, has been closed. The system must be equipped with its own drain valve, which is to be suitably sized according the system s capacity. Prima della progettazione della centrale termica verificare sul sito www.unical.eu le posizioni degli attacchi.
Stainless steel condensing units FLUE CONNECTION AND CONDENSATE DRAIN Condensate drain The boiler, during the combustion process, produces condensation that, through pipe A, flows into the trap. The condensation that forms inside the boiler flows into a suitable drain via pipe B. The upper generator of the drain pipe must not be higher than the bottom of the pan. at condensate drain 420 170 320 280 H BOILER ROOM FLOOR H = Siphon head Capacity conditions 0 and Max Fan Head SPK 150-230 = 420 mm SPK 300 = 320 mm SPK 348 600 = 280 mm If you do not want to or cannot create a basement, the boiler can be mounted at ground level and a bulb holder 250 mm deep can be made to house the siphon.
Stainless steel condensing units SPK 150 600 TYPE AND SHAPE OF THE FURNACE Vertical furnace Truncated cone shaped combustion chamber Construction in stainless AISI 316 L Sized for premix burner Model Combustion chamber volume m 3 Combustion chamber surface m 2 SPK 115 0.06 9.5 SPK 150 0.06 9.5 SPK 230 0.11 15.6 SPK 300 0.135 18 SPK 400 0.216 25 SPK 400 0.216 25 SPK 500 0.220 25 SPK 600 0.240 32 3 Combustion chamber of SPK 150 Combustion chamber of SPK 230 to 600 SPECIAL SMOKE PIPES (patented) SMOKE PIPES: Exceptional thermal exchange Functional outflow of the condensate Absence of wet acidic deposits Washout, for gravity, of the smooth exchange surfaces Greater duration Multi-radial aluminium fins External pipe in stainless steel AISI 316L
Stainless steel condensing units HYDRODYNAMIC STRUCTURE OF THE OUTER SHELL The thermal exchange with the installation is guaranteed by specific return manifold placed in such position to guarantee the maximum efficiency of the heat exchanger. Both, the large diameter manifold and the large water content guarantee the maximum water circulation with the minimum pressure losses. The water, through the forced circulation, surrounds completely the stainless steel heat exchanger (combustion chamber and smoke pipes) and, heated, is pushed towards the flow connection. The special design of the heat exchanger allows the complete shut down of the boiler, with zero water circulation, without the need of recirculation pumps. This guarantees the reduction of the installation costs and the electrical running consumption. FEATURES OF THE DOOR The combustion chamber door is in carbon steel with insulation in super light recyclable concrete and is endowed with pneumatic cushion. Casing is insulated with fabric-finished mineral wool, 50 mm thick. TYPE OF BURNER GAS VALVE (Side view) PG Min (*) PG Max (**) PG Min (**) S R PG=GAS PRESSURE SWITCH S=ADJUSTMENT SCREW MAXIMUM OUTPUT R=ADJUSTMENT SCREW MINIMUM OUTPUT (*) PG Min SPK 115 / 230 / 300 (**) PG Max e PG Min - only on SPK 348 / 400 / 500 / 600 The delivered output depends on the rpm of the fan serving the gas valve. The flame control is managed directly by the electronic PCB of the burner, endowed of BMM (=Burner Module Manager). The opening of the gas valve is generated by Venturi effect in the VOLUTE of the fan and the air-gas mixing happens in its inside, before being sent in the combustion chamber (premix). The combustion happens on the surface of the special cylindrical burner in FeCr alloy fibre. The wide flame surface guarantees: low combustion temperature reduced turbulence with the following advantages: higher transferred energy if compared with a traditional burner with the same flame temperature absolute working safety for the absence of turbulences low pollution thanks to the complete oxidation of the natural gas molecules optimum combustion efficiency: maximum CO 2 = 9.3% fast achievement of the condensation conditions, since 54 C optimization of the efficiency thanks to the low smoke temperature and the low air excess minimum NOx emissions, Class 5 (see table of technical data)
Stainless steel condensing units SPK 150 600 BASIC ELECTRICAL CONNECTIONS THERMOREGULATION HSCP (std. supplied) BCM Boiler Cascade Manager (std. supplied) THERMOREGULATION E8 (optional) BASIC ELECTRICAL CONNECTIONS 4 5 1 7 3 2 8 6 1. PCB for management of the burner 2. Terminal strip for electrical supply 230 V 3. Boiler controller BCM 4. Fuse 4-6.3 A on electrical supply 5. PCB for supply 6. Limit thermostat with manual reset 7. Additional terminal strip for +24V BCM 8. Cable clamp for supply cable
Stainless steel condensing units BASIC ELECTRICAL CONNECTIONS The boiler is supplied with the predisposition to manage a direct flow and DHW tank. If Stemp ACC is connected, automatically will be activated the DHW service, which will have the priority on the pumps shown in the below figures. If the management of addidional services is required (DHW tanks, mixed zones, solar system, etc.) it will be necessary to buy multifunction SHC to be connected to the local bus for the complete management through the HSCP controller. P. Coll. P. CH P. Car. DHW P. Mod. If the DHW tank temperature sensor is connected, automatically the DHW service is activated when the boiler is electrically fed. The code (803) Srv (see BCM parameters) moves from 19 to 27 Connect the cables on Y4 1-2 as indicated Connect the cables on Y3 1-2-3 as indicated Connect the cables for modulation control as indicated (Y2 4-5). Electrical supply is external. Connect the cables of the temperature sensor as indicated (Y2 4-8) P. Coll - Optional manifold pump (Primary ring) P. CH Central Heating Pump (Heating circuit) P. Car DHW DHW tank loading pump P. Mod Modulating Pump (optional) Stemp ACC DHW tank temperature sensor (optional) Collegamento Sicurezze (Y2 9 & Terminal strip M2) after removal of the jumper Remove the jumper and connect the cables as indicated (Y2 11 & Terminal strip M2) Remove the jumper and connect the cables as indicated (Y2 10 & Terminal strip M2) Predisposto alla morsettiera, BCM (Y2 6-7) Parameter TA (optional) Additional safety connection Connection of Flow switch FL Connection of Outer sensor (optional)
Stainless steel condensing units SPK 150 600 TECHNICAL DATA ELECTRICAL, HYDRAULIC, INSTALLATION DIAGRAMS AND CONTROLLERS can be unloaded from the web site www.unical.eu at the page of the product SPK 150 230 300 348 400 500 600 Boiler category II 2H3P II 2H3P II 2H3P II 2H3P II 2H3P II 2H3P II 2H3P Modulation ratio 1:4.0 1:4.3 1:4.3 1:3.9 1:4.2 1:3.9 1:4.4 Rated heat output on P.C.I. Qn kw 140 214 280 348 380 450 550 Minimum heat output on P.C.I. Qmin kw 35 50 65 90 90 115 125 Rated useful power (Tr 60 / Tm 80 C) Pn kw 136.33 209.25 273.76 339.4 371.56 440.1 534.5 Minimum useful power (Tr 60 / Tm 80 C) Pn min kw 32.49 48.21 62.00 87.7 86.08 110.0 118.5 Rated useful power (Tr 30 / Tm 50 C) Pcond kw 145.94 226.80 292.77 360.1 399.00 472.2 578.2 Minimum useful power (Tr 30 / Tm 50 C) Pcond min kw 36.65 54.61 70.03 99.14 97.16 124.0 135.2 Rated power performance (Tr 60 / Tm 80 C) % 97.38 97.78 97.77 97.52 97.78 97.81 97.2 Minimum power performance (Tr 60 / Tm 80 C) % 92.82 96.46 95.39 97.41 95.64 95.62 94.8 Rated power performance (Tr 30 / Tm 50 C) % 104.24 105.98 104.56 104.43 105 104.93 105.1 Minimum power performance (Tr 30 / Tm 50 C) % 104.72 109.22 107.74 110.15 107.95 107.86 108.2 Performance at 30% of the load (Tr 30 C) % 107.65 107.18 108.99 108.39 108.98 108.97 106.5 Combustion efficiency at nominal load % 97.59 97.43 97.47 97.78 97.35 97.02 97.00 Combustion efficiency with reduced load % 98.41 98.33 98.28 98.35 98.33 98.25 98.4 Casing heat loss with burner operating (Qmin) % 5.59 1.91 2.89 2.60 2.69 2.63 3.6 Casing heat loss with burner operating (Qn) % 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Net flue gas temperature tf-ta (min)(*) C 32.3 33.6 34.6 33.2 33.7 34.3 31.5 Net flue gas temperature tf-ta (max)(*) C 49 51.7 51 44.8 53.3 60.0 61.0 Maximum permitted temperature C 100 100 100 100 100 100 100 Maximum operating temperature C 85 85 85 85 85 85 85 Flue gas mass flow rate (min) kg/h 56.16 80.97 105.26 145.87 107.0 131.5 141.7 Flue gas mass flow rate (max) kg/h 224.60 346.57 453.47 563.58 621.05 728.67 898.97 Excess air % 23.00 24.25 24.25 24.25 24.25 26.84 25.5 Heat loss at chimney with burner on (min) % 1.59 1.67 1.72 1.65 1.67 1.75 1.58 Heat loss at chimney with burner on (max) % 2.41 2.57 2.53 2.22 2.65 2.98 3.05 Minimum heating circuit pressure bar 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Maximum heating circuit pressure bar 6 6 6 6 6 6 6 Boiler maximum allowable working pressure bar 8 8 8 8 8 8 8 Water content l 153 210 270 340 340 340 425 Methane gas consumption G20 (pow.sup. 20 mbar) at Qn m 3 /h 14.80 22.63 29.61 36.80 40.18 47.58 58.16 Methane gas consumption G20 (pow.sup. 20 mbar) at Qmin m 3 /h 3.70 5.29 6.87 9.52 9.52 12.16 13.22 Gas consumption G25 (pow.sup. 20/25 mbar) at Qn m 3 /h 17.22 26.32 34.43 42.80 46.73 55.34 67.64 Gas consumption G25 (pow.sup. 20/25 mbar) at Qmin m 3 /h 4.30 6.15 7.99 11.07 11.07 14.14 15.37 Propane gas consumption (pow. sup. 37/50 mbar) at Qn kg/h 10.87 16.61 21.73 27.01 29.50 34.93 42.69 Propane gas consumption (pow. sup. 37/50 mbar) at Qmin kg/h 2.72 3.88 5.05 7.09 6.99 8.93 8.70 Chimney base maximum pressure available Pa 100 100 100 100 100 100 100 Max condensate production kg/h 11.3 13.7 15.8 29.1 28.5 28.8 31.0 Emissions CO at maximum heat output with 0% of O 2 mg/kwh 13 17 17 24.7 16 22.7 24.8 NO x at maximum heat output with 0% of O 2 mg/kwh 34 50 40 65 49 56 68.4 NO x Class 5 5 5 5 5 5 5 Electrical data Power supply voltage/frequency V/Hz 230/50 230/50 230/50 230/50 230/50 230/50 230/50 Fuse on the power supply A (R) 6 6 6 6 6 6 6 Protection rating IP X4D X4D X4D X4D X4D X4D X4D Technical updates are underway for the SPK series. We recommend checking on www.unical.eu Room Temperature = 20 C. (*) Temperatures detected with the unit in operation (Tr 60 / Tm 80 C) Seasonal Efficiency ηs according to Directive 2009/125/EC for Outputs < = 400 kw. See Erp Table Standstill heat losses at Δt 30K P stby See Erp Table Standstill electrical consumption P sb See Erp Table
Stainless steel condensing units TECHNICAL DATA ACCORDING TO ErP DIRECTIVE ELECTRICAL, HYDRAULIC, INSTALLATION DIAGRAMS AND CONTROLLERS can be unloaded from the web site www.unical.eu at the page of the product SPK 150 230 300 348 400 500 600 EFFECTIVE NOMINAL OUTPUT P n kw 136 209 274 339 371 440 534 SEASONAL ENERGY EFFICIENCY TO HEAT THE ROOM η s % 93 92 94 94 94 94 92 SEASON EFFICIENCY CLASS TO DISCHARGE A A A A A * * FOR BOILERS TO HEAT THE ROOM AND MIXED BOILERS: USEFUL HEAT OUTPUT USEFUL HEAT OUTPUT with high temperature capacity (Tr 60 C / Tm 80 C) RATED HEAT OUTPUT EFFICIENCY with high temperature capacity (Tr 60 C / Tm 80 C) USEFUL POWER AT 30% OF THE RATED HEAT OUTPUT with low temperature capacity (Tr 30 C) PERFORMANCE AT 30% OF THE RATED HEAT OUTPUT with low temperature capacity (Tr 30 C) P 4 kw 136.3 209.3 273.8 339.4 371.6 440.1 534.5 η 4 % 87.8 88.1 88.1 87.9 88.1 88.1 87.6 P 1 kw 45.2 68.8 91.6 113.2 124.2 147.1 175.8 η 1 % 96.9 96.6 98.2 97.7 98.1 98.2 96.0 BOILER WITH OUTPUT RANGE ADJUSTMENT: YES / NO NO NO NO NO NO NO NO AUXILIARY ELECTRICITY CONSUMPTION WITH A FULL LOAD el max kw 0.190 0.195 0.210 0.270 0.425 0.555 0.590 WITH A PARTIAL LOAD el min kw 0.042 0.040 0.032 0.036 0.051 0.053 0.088 STANDBY MODE P SB kw 0.005 0.005 0.005 0.005 0.005 0.004 0.007 OTHER ELEMENTS HEAT DISPERSION ON STANDBY P stby kw 0.32 0.39 0.34 0.95 0.95 0.95 1.34 NITROGEN OXIDES EMISSIONS NO x mg/kwh 67 61 59 65 53 56 62 FOR MIXED HEATING APPLIANCES DECLARED LOAD PROFILE - - - - - - - WATER HEATING ENERGY EFFICIENCY η WH % - - - - - - - DAILY CONSUMPTION OF ELECTRICITY Q elec kwh - - - - - - - DAILY CONSUMPTION OF FUEL Q fuel kwh - - - - - - - INTERNAL SOUND POWER LEVEL Lwa db(a) - - - - - - - SEASONAL DHW EFFICIENCY CLASS - - - - - - - Technical updates are underway for the SPK series. We recommend checking on www.unical.eu * (Appliances not covered by Directive 2009/125/EC)
Stainless steel condensing units SPK 150 600 WATER SIDE PRESSURE DROPS DIAGRAM Pressure drop (m H 2 O) Flow rate (m 3 /h)
Stainless steel condensing units DETERMINATION OF THE PRIMARY CIRCUIT PUMP SPK 150 Maximum flow rate in l/h (Dt=8K) 14.655 Maximum flow rate in l/h (Dt=15K) 7.816 Requested rated output in l/h (Dt=20K) 5.862 SPK 230 Maximum flow rate in l/h (Dt=8K) 22.495 Maximum flow rate in l/h (Dt=15K) 11.997 Requested rated output in l/h (Dt=20K) 8.998 SPK 300 Maximum flow rate in l/h (Dt=8K) 29.426 Maximum flow rate in l/h (Dt=15K) 15.695 Requested rated output in l/h (Dt=20K) 11.772 SPK 348-400 Maximum flow rate in l/h (Dt=8K) 39.883 Maximum flow rate in l/h (Dt=15K) 21.303 Requested rated output in l/h (Dt=20K) 15.997 SPK 500 Maximum flow rate in l/h (Dt=8K) 47.300 Maximum flow rate in l/h (Dt=15K) 25.606 Requested rated output in l/h (Dt=20K) 19.203 SPK 600 Maximum flow rate in l/h (Dt=8K) 57.405 Maximum flow rate in l/h (Dt=15K) 30.616 Requested rated output in l/h (Dt=20K) 22.962 NOTE: The pumps must be determined by the installer or designer according to the boiler and system data. The pump is not an integral part of the boiler. (See the installation manual) MODULATING PUMP TWIN MODULATING PUMP