union swing check valve spring loaded check valve purging valve pressure relief valve relief valve metered balancing valve

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VENT APPENDIX A: PIPING SYMBOL LEGEND GENERIC COMPONENTS CALEFFI COMPONENTS circulator circulator w/ ThermoBloc union circulator w/ swing check spring loaded balancing balancing w/ gate check globe s purging ball pressure reducing thermostatic radiator pressure relief zone (2 way) Hydro Separator thermostatic radiator pressure & temperature zone (3 way) relief strainer pressure relief primary/secondary metered balancing differential hose bib pressure bypass air & dirt separator drain brazed plate DIRTCAL diverter tee heat dirt separator exchanger cap Hydrolink conventional boiler manifold station with balancing s distribution station solar circulation station mixing units Modulating / condensing boiler indirect water heater (with trim) high temperature high temperature mixing solar DISCAL air separators isolar differential high temperature solar pressure temperature controller relief solar collector array high temperature solar air vent high temperature solar high temperature solar air vent expansion tank 46

APPENDIX B: SIZING DIAPHRAGM-TYPE EXPANSION TANKS Figure B-2 All closed-loop hydronic systems require expansion tanks regardless of the heat source used Closed-loop systems with wood-fired boilers and relatively large buffer tanks often require substantially larger expansion tanks due to the volume of water in the system This appendix presents information for sizing the diaphragm-type expansion tanks commonly used in residential and light commercial systems A properly sized diaphragm-type expansion tank allows the pressure relief to reach a pressure about 5 psi lower than its rated opening pressure when the system reaches its maximum operating temperature The 5 psi margin prevents the relief from leaking just below its rated opening pressure The first step in sizing a diaphragm-type expansion tank is to determine the proper air-side prepressurization of the tank using Formula B-1 Formula B-1 Where: Pa = air-side pressurization of the tank (psi) H = distance from inlet of expansion tank to top of system (ft) Dc = density of the fluid at its initial (cold) temperature (lb/ft 3 ) The proper air-side prepressurization is equal to the static fluid pressure at the inlet of the tank, plus an additional 5 psi allowance at the top of the system The pressure on the air-side of the diaphragm should be adjusted to the calculated prepressurization value before fluid is added to the system This is done by either adding or removing air through the Schrader on the shell of the tank A small air compressor or bicycle tire pump can be used when air is needed An accurate 0 to 30 psi pressure gauge should be used to check this pressure as it is being adjusted Many smaller diaphragm-type expansion tanks are shipped with a nominal air-side prepressurization of 12 psi However, the air-side pressure should always be checked before installing the tank Proper air-side pressure adjustment ensures the diaphragm will be fully expanded against the shell of the tank when the system is filled with fluid, but before it is heated Failure to properly prepressurize the tank can result in the diaphragm being partially compressed by the fluid s static pressure before any heating occurs If this occurs, the full expansion volume of the tank will not available as the fluid heats up Figure B-1 47

Once the air-side prepressurization is determined, Formula B-2 can be used to find the minimum required volume of the expansion tank: Formula B-2 Where: V t = minimum required tank volume (gallons) Not acceptance volume Vs = fluid volume in the system (gallons) Dc = density of the fluid at its initial (cold) temperature (lb/ft 3 ) D h = density of the fluid at the maximum operating temperature of the system (lb/ft 3 ) P a = air-side pressurization of the tank found using Equation B-1 (psi) PRV = rated pressure of the system s pressure-relief (psi) System volume can be estimated based on the total volume of the boiler, piping and other components in the system Figure B-1 gives volumes for several common pipe types and sizes used in residential and light commercial systems The density of water over the temperature range of 50º to 250ºF can be read from Figure B-2 Example: Determine the minimum-size diaphragm-type expansion tank for the system shown and described in Figure B-3 Boiler volume = 20 gallons Piping estimates: 50 feet of 15 copper 100 feet of 1 copper 2000 feet of 1/2 PEX Miscellaneous component volume = 3 gallons Maximum buffer tank temperature = 200ºF Minimum system water temperature = 50ºF Vertical distance from top of system to inlet of expansion tank = 12 feet Pressure relief setting = 30 psi Solution: Start by getting the density of water at both extremes: D50ºF = 624 lb/ft3 D200ºF = 6015 lb/ft3 The total estimated system volume is found by totaling up the volume in piping and other components: Vs = (50)(009505) + (100)(00454) + (2000)(0009609) + 23 + 2(119) = 290 gallons Formula B-1 can now be used to calculate the cold fill pressurization of the expansion tank: Formula B-2 can now be used to calculate the expansion tank volume: Figure B-3 48

Discussion: This expansion tank volume is conservatively large because it assumes that all water in the system reaches the upper temperature of 200ºF simultaneously This is not the case for piping downstream of the mixing (eg, the radiant panel circuits) Thus, it is not necessary to add any additional safety factor to this volume The expansion tank volume is also considerably larger than required in most residential hydronic systems This is a direct result of the large buffer tank volume (238 gallons) out of the total system volume (290 gallons) In this case, the expansion tank volume was approximately 10% of the total system volume Given similar system operating conditions, it is reasonable to make a rough estimate of expansion tank volume using the 10% rule of thumb However, variations in temperature, height or pressure-relief settings should always be evaluated using the above procedure 49

ThermoMix boiler protection high-flow thermostatic mixing series 280 CALEFFI Function The ThermoMix boiler protection high-flow thermostatic mixing is used in hydronic heating systems with non-condensing boilers, including solid fuel, biomass, gas, LP or oil-fired It can be installed with steel, cast iron and copper tube style boilers, automatically controlling the return water temperature, preventing condensation of the water vapor contained in the flue gas The 280 series ThermoMix mixes bypass flow from the boiler with return flow from the system, sending a fixed temperature flow to the boiler which protects against corrosion from condensation occurring when a minimum flue gas temperature is not otherwise maintained Changable thermostatic sensor cartridges modifies temperature setting The thermostatic sensor cartridge can easily be removed for maintenance or to change the set temperature, with out removing the body from the piping Product range Code 280xxxA Boiler protection high-flow thermostatic mixing with 140ºF cartridge, threaded and sweat connections sizes 1, 1-1/4 Code F29633 Themostatic sensor cartridge 115º F Code F29634 Themostatic sensor cartridge 130º F Code F29635 Themostatic sensor cartridge 140º F Code F29636 Themostatic sensor cartridge 160º F Technical specifications Materials Body and lower body plug: Shutter: Spring: Seal: Union seals: Thermostatic sensor: brass polysulfone stainless steel EPDM non-asbestos fiber wax Dimensions Performance Suitable fluids: water, up to 50% glycol solutions Max working pressure: Working temperature range: Thermostatic sensor cartridge: 150 psi (10 bar) 40-212 F (5-100 C) 140 F (60 C) standard 115 F (45 C), 130 F (55 C), 160 F (70 C) optional cartridges Sensor cartridge accuracy: By-pass from boiler complete closing temperature: Cv: ±36 F (±2 C) Tset +18 F (10 C) size 1 10Cv size 1-1/4 14Cv Connections: - NPT male union 1 and 1¼ - sweat union 1 and 1¼ 140º F 150 psi Code A B C D E F 280166A 1 NPT 3 1/2 7 6 1 5/8 4 3/8 280966A 1 SWT 3 1/2 7 6 1 5/8 4 3/8 280176A 1 1/4 NPT 3 13/16 7 5/8 6 3/16 1 9/16 4 3/8 280976A 1 1/4 SWT 3 13/16 7 5/8 6 3/16 1 9/16 4 3/8 50

Characteristic components Valve body Spring Thermostatic sensor Bypass from boiler Temp gage pocket wells (4) Shutter Construction details The brass body prevents the formation of ferrous residues in the system, prolonging boiler operating life The thermostatic sensor can be easily replaced for maintenance or set point change The boiler protection mixing body features temperature gage pocket wells on front and rear sides, allowing installation of a temperature gage (code F29571) for monitoring the working temperatures: bypass from boiler, return from system, and mixed Flow curve 1 1-1/4 p (psi) 21 Plug System return 45 Operating principle 7 The thermostatic sensor, completely immersed in the medium, controls the movement of a shutter that regulates the bypass flow from the boiler and toward the system At boiler startup, the boiler protection thermostatic mixing recirculates the bypass flow from the boiler to bring the boiler up to temperature as quickly as possible (fig 1) When the bypass flow from the boiler Tf exceeds the setting of the boiler protection mixing Tset, the s return from the system port starts opening to produce the water mixing Tmix: in this phase the system loading begins (fig 2) When the mixed flow to the boiler temperature Tmix is greater than the set point of the boiler protection mixing by approximately 18 F (10 C), the bypass flow from the boiler port closes and water returns to the boiler at the same temperature as the return flow from the system 2 10 4 20 9 Cv: size 1 10 size 1-1/4 14 22 44 200 43 3 15 07 88 F lowrate (l/min) (gpm) Tf Tset SYSTEM START UP by-pass open system return closed Tf Tset, Tmix=Tf 1 Tf > Tset START OF SYSTEM LOADING by-pass open system return open Tf > Tset, Tr < Tset, Tmix=Tset 2 SOLID FUEL BOILER f SOLID FUEL BOILER f Tmix = Tset + 18 F BY-PASS CLOSING by-pass closed system return open Tf > Tmix = Tset +18 F, Tmix=Tr 3 Tmix > Tset + 18 F SYSTEM LOADED by-pass closed system return open Tf > Tmix > Tset +18 F, Tmix=Tr 4 SOLID FUEL BOILER f SOLID FUEL BOILER f Tf=Bypass flow from boiler Tset=Boiler protection set point temperature Tmix= flow temperature Tr= temperature 51

210º F ThermoBloc Boiler protection recirculation and distribution unit series 281 CALEFFI Product range Function The ThermoBloc boiler protection recirculation and distribution unit is used in hydronic heating systems with non-condensing boilers, including solid fuel, biomass, gas, LP or oil-fired It can be installed with steel, cast iron and copper tube style boilers, automatically controlling the return water temperature, protecting against corrosion from condensation occurring when a minimum flue gas temperature is not otherwise maintained The ThermoBloc unit is compact for easy installation, reducing required space and fittings It combines the functionality of a boiler protection with a circulation pump and a unique flapper check allowing for thermosyphon flow between the boiler and distribution system during a power outage The ThermoBloc includes three temperature gages and is encased in an insulation shell Code 281xxxA Boiler protection unit, with 140º F cartridge, threaded and sweat connections sizes 1, 1-1/4 Technical specifications Materials Body: Shutter: Spring: Flapper check Seal: Thermostatic sensor: brass PSU stainless steel PPS EPDM wax Dimensions Performance Suitable fluids: water, up to 50% glycol solutions Max working pressure: 150 psi (10 bar) Working temperature range: 40-210 F (5-100 C) Termperature gage scale: 30-250 F (0-120 C) Thermostatic sensor cartridge: 140 F (60 C) standard 115 F (45 C), 130 F (55 C), 160 F (70 C) optional cartridges Sensor cartridge accuracy: ±36 F (±2 C) Bypass from boiler complete closing temperature: Tset +18 F (10 C) 140º F 150 psi Connections: - NPT male union 1 and 1-1/4 - sweat union 1 and 1-1/4 Pump Three speed pump: Body: Power supply: 115 V - 60 Hz Max pressure: Max temperature: Agency approval: Wilo Star S-16 U15 cast iron 150 psi (10 bar) 230 F (110 C) culus Code A B C D E F G 281166A 1 NPT 8 3/4 5 5/8 3 9 7/8 1 7/8 8 281966A 1 SWT 8 3/4 5 5/8 3 9 7/8 1 7/8 8 281176A 1 1/4 NPT 8 3/4 5 5/8 3 9 7/8 1 7/8 8 281976A 1 1/4 SWT 8 3/4 5 5/8 3 9 7/8 1 7/8 8 281 Pump characteristcs Insulation Material: EPP Mean thickness: 30 mm Density: 45 kg/m 3 Working temperature range: 40-210 F (5-100 C) Thermal conductivity: 0037 W/(m K) at 10 C Reaction to fire (UL94): class HBF 52

Characteristic components 4 Ritorno l generatore Three-speed pump Valve body 5 By-pass from boiler Valve for natural circulation Temp gauge pocket well (3) Shuttle Thermostatic sensor 3 Tf Tset BOILER START UP Tf Tset, Tmix=Tf Tmix Tf > Tset START OF SYSTEM LOADING Tf > Tset, Tr < Tset, Tmix=Tset By-pass from boiler Tf 4 Ritorno impianto Tf Tset By-pass from boiler by-pass open system return closed Tr 1 2 Operating principle The thermostatic sensor, completely immersed in the medium, controls the movement of a shutter that regulates the bypass flow from the boiler and toward the system At boiler startup, the boiler protection recirculation and distribution unit recirculates the bypass flow from the boiler to bring the boiler up to temperature as quickly as possible (fig 1) When the bypass flow from the boiler Tf exceeds the setting of the fixed thermostatic sensor Tset, the unit s return from the system port starts opening to produce the water mixing Tmix: in this phase the system loading begins (fig 2) When the mixed flow to the boiler temperature Tmix is greater than the set point of the boiler protection recirculation and distribution unit by approximately 18 F (10 C), the bypass flow from the boiler port closes and water returns to the boiler at the same temperature as the return flow from the system (fig 3) When power is out and the circulation pump stops running, the flapper check, which is closed during normal operation, opens with a slight pressure differential resulting from the effects of heated water in the boiler and cooler water in the distribution syste, a natural thermosyphon flow This prevents a excessive heat buildup which eventually would cause the pressure relief to open(fig 4) Tmix Tmix > Tset + 18 F SYSTEM LOADED Tf > Tmix > Tset +18 F, Tmix=Tr Tset By-pass from boiler Tf by-pass open system return open Tr 3 by-pass closed system return open The compact brass body casting houses the pump and all functioning components, offering easy installation, either on the right or left side of the boiler The temperature gages can be easily removed and re-inserted on the back side of the unit The brass body prevents the formation of ferrous residues in the system, prolonging boiler operating life The unit features a thermostatic sensor to control the temperature of water returning to the boiler to prevent condensation The sensor can be easily replaced for maintenance or set point change Tmix PUMP OFF Normally closed check opens due to buoyancy forces to allow thermosyphon flow Tset By-pass from boiler Tf Tr 4 The flapper check allows the natural thermosyphon circulation of the system heat transfer fluid when the pump stops running due to power failer When the pump is running under normal conditions the thust of the flowing medium keeps the flapper closed, forcing flow past the thermostatic sensor When the pump stops running and the fluid in the boiler is at high temperature, natural circulation begins, bypassing the thermostatic sensor, preventing overheating in the boiler Tmix Tset by-pass open system return closed Tr 53

ThermoCon buffer storage tanks series NAS200 CALEFFI Function ThermoCon tanks are designed to be used for wood boilers, solar and geothermal storage, plus in heating systems with low-mass boilers, chilled water systems and low-mass radiation ThermoCon tanks are used in systems operating below the design load condition, which is most of the time, or in systems having several low cooling or heating loads demands at different times Boilers operating at low loads will short cycle, resulting in reduced operating efficiency and shorter equipment life When piped correctly, the ThermoCon will serve as both a thermal buffer and a hydraulic separator The solar, boiler or chiller system will be hydraulically separated from the distribution system Meets and exceeds CSA C309 requirements Product range Code NAS20050 Storage tank 50 gallon Code NAS20080 Storage tank 80 gallon Code NAS20120 Storage tank 120 gallon Technical specifications Dimensions Tank materials: Tank insulation: Tank external cover: Insulation thermal conductivity: Connections: porcelain coated steel 2" non-cfc foam powder-coated steel (20-24 ga) R16 top (3) 3/4" NPT female side (7) 2 NPT female Maximum working pressure: 150 psi Testing pressure: 300 psi Maximum tank temperature: 180 F Recommended maximum delivery hot water temperature: 120 F Construction details 2 NPT 8 4 ¾ NPT A 2 NPT 2 NPT D C B The ThermoCon tanks are engineered with seven (7) 2 NPT connections Two connections can be piped to the solar, boiler or chiller side and two connections can be piped to the distribution system Two additional connection are 90 degree from another which allows for positioning tank into a corner with the piping at a right angle The tank has one 2 NPT connection for connecting an external heat exchange in the middle of the tank F E A Model A B C D E F NAS20050 22 48¼ 39½ 23½ 7¾ 4½ NAS20080 24 64 53 32 11 5 NAS20120 28 65 53 32 11 7 54

Applications air vent! w/ shut off solar collector array solar! circulation! station extensively zoned distribution system 3-way! motorized! mixing zone! s (P1) DHW! HX small circulator (P2) with check tankless electric! water heater variable speed! pressure regulated! circulator DHW CW wood-fired boiler ThermoCon! buffer tank extensively zoned distribution system 3-way! motorized! mixing zone! s (P1) DHW! HX small circulator with check tankless electric! water heater DHW variable speed! pressure regulated! circulator CW wood-fired Comp boiler ThermoCon! buffer tank compressor evaporator condenser bypass flow switch bypass (P3) flow switch TXV water-to-water! heat pump (heating only) geothermal manifolds purging! s earth loop circuits 55