Circulators high efficiency ECM Circulators
Circulators high efficiency ECM Circulators Small ECM circulators now available in North America Grundfos Alpha: Provides constant and proportional differential pressure and three fixed speed settings. 6-50 watt electrical input. Wilo Stratos ECO 16F: Provide constant and proportional differential pressure. 5.8-59 watt electrical input. Bell & Gossett ECOCIRC, Provides manual adjustable speed setting (VARIO model), and proportional differential pressure (AUTO model). 5-60 watt electrical input. Taco Bumblebee Temperature based speed control. 9-42 watts electrical input Armstrong COMPASS Provides constant and proportional differential pressure and three fixed speed settings. 3-45watt electrical input.
Circulators high efficiency ECM Circulators Larger ECM circulators now available in US Wilo STRATOS circulators Grundfos MAGNA Taco Viridian Heads to 45 feet, flows to 345 gpm power inputs to 1600 watts B&G ECO XL
Circulators All these circulators rated A on the energy labeling system from Europump (European Association of Pump Manufacturers). high efficiency ECM Circulators European circulator rating system Single or multi-speed wet-rotor circulators like those commonly used in North America would be rated D or E on this scale.
Homerun distribution systems TRV TRV
The vast majority of hydronic distribution system developed in North America over decades were based on rigid piping. Bell & Gossett Circa 1949
PEX tubing was introduced in North America in the early 1980s, and was viewed primarily for use in radiant floor heating applications.
Slowly, some North American designers/installers began mixing PEX and PEX-AL-PEX tubing into system along with rigid tubing.
At this point, many North American heating pros recognize PEX or PEX-AL-PEX as a universal hydronic distribution pipe. One of the best approaches using this pipe is a homerun system.
Concept: Treat the tubing like electrical cable: If you can run an electrical cable from point A to point B within a building, you can also probably run a small diameter flexible tube set.
Examples of homerun distribution systems thermostatic operator air vent baseboard #6 ent towel warmer radiator baseboard #5 dual isolation valve TRV baseboard #4 baseboard #3 baseboard #2 pressure regulated! variable speed circulator PEX, or! PEX-AL-PEX tubing manifold station thermostatic radiator valves (TRV) baseboard #1 1/2" PEX-AL-PEX! tubing pressure regulated! circulator manifold station
Examples of homerun distribution systems differential pressure! bypass valve! (closed at design load) 24VAC valve actuators
A simple but elegant concept panel radiator TRV thermostatic radiator valves! on each panel radiator TRV TRV TRV TRV TRV pressure-regulated! variable speed circulator 1/2" PEX or PEX-AL-PEX tubing thermal storage tank manifold station + homerun piping thermostatic radiator valves pressure regulated circulator thermal mass @ heat source hydronics heaven
Hydronic Zoning Options
Hydronic Zoning Options A zone in an area of a building in which the temperature is controlled by a single thermostat, or other temperature sensing device. Two principal objectives of zoning: 1. Create desirable comfort conditions in various areas of a building 2. Reduce heating energy use by reducing space temperature when possible A zone can be as small as a single room, or as large as an entire building. The quality of a zoned system is not judged by the number of zones. Although itʼs possible to make every room its own zone, it is not often necessary, and can add considerable cost and complexity There is no absolute right way to zone a building. It depends on specifics of the building as well as occupant preferences:
Hydronic Zoning Options Zoning considerations: Areas with signifiant internal heat gain from sunlight, appliances, people or equipment, should be separate zones. Sleeping areas are often set up as separate zones from daytime activity areas. Areas of the building that are infrequently used should be separate zones. Garages, basements, exercise rooms, workshops are often separate zones Master bathrooms are often zoned separately to master bedrooms (cool bedrooms and warm bathrooms. The 2nd floor of a house is often zoned separately from 1st floor.
Hydronic Zoning Options Zoning considerations: Consider thermal mass of the heat emitters Donʼt combine high mass and low mass heat emitters on the same zone. mean slab temperature (ºF) 78 76 74 72 70 68 66 64 62 60 medium mass! (1.5" concrete slab)! radiant floor panel high mass (6" concrete slab)! radiant floor panel 2400 sq. ft. slab on grade 60,000 Btu/hr! heat! input 0 5 10 15 20 elaped time from first heat input (hours) indoor temperature ((ºF) 70 68 66 64 62 60 58 room with lower thermal mass! and higher heat loss room with high thermal mass! and low heat loss 56 0 1 2 3 4 5 6 7 8 9 10 Time from end of heat input (hours) T r = T o + [ T ri! T o ]e! " UA % $ 't # h & Where:! Tr = temperature of room (ºF)! To = outdoor temperature! Tri = initial temp. of room when heat input stops (ºF)! e = 2.718281828! UA = heat loss coefficient of room (Btu/hr/ºF)! h = heat capacitance of room's thermal mass (Btu/ºF)! t = elapsed time without heat input (hr)
Hydronic Zoning Options Zoning considerations: Consider heat flow through interior partitions The low the heat loss of the building envelope, the more difficult it is to maintain interior temperature differences - especially if doors are left open.
Hydronic Zoning Options Methods of zoning 1. Zoning with on/off zone valves 2. Zoning with on/off manifold valve actuators 3. Zoning with on/off zone circulators 4. Zoning with wireless thermostatic radiator valves
go on SUPPLY side of circuit. Hydronic Zoning Options 1. Zoning with on/off zone valves Zone valves should go on SUPPLY side of circuit. Recommend 4-wire zone valves as most versatile. zone! valves fixed speed circulator differential! pressure! bypass valve VENT If a fixed speed circulator is used: 1. It should have a flat pump curve 2. the system should have a P bypass valve.
1. Zoning with on/off zone valves "flat" pump curve "steep" pump curve D 144!P = ( Head ) % ' & " $ # head large change in P " (undesireable) fixed speed circulator differential pressure bypass valve system curve (1 zone on) system curve (2 zones on) system curve (3 zones on) small change" in P (desireable) flow rate zone valves truncated pump curve (when DPBV is operating! above threshold setting) threshold P! setting of DPBV DHW D 144 % ' & pump! curve low flow resistance! common piping! CW!P = ( Head ) " $ # head indirect water heater flow rate (1 zone on) (2 zones on) system head loss curve (3 zones on) Design tip: Fixed speed circulator in combination with P bypass valves are on their way out. Modern systems will use ECM-based variable speed, pressure regulated circulators.
Hydronic Zoning Options 1. Zoning with on/off zone valves variable speed! (pressure regulated) circulator low flow resistance! common piping! zone valves head added / loss (feet) head added / loss (feet) 20 15 10 5 0 20 15 10 5 0 system head loss curves (1) zone on perfectly flat pump curve (2) zones on (3) zones on 0 2 4 6 8 10 12 flow rate (gpm) (4) pump curves decreasing circulator speed system head loss curves (1) zone on constant differential pressure control (2) zones on (3) zones on (4) 0 2 4 6 8 10 12 flow rate (gpm) 8 6 4 2 0! " # %! P =! H $ D & 144 8 6 4 2 0! " # %! P =! H $ D & 144 Variable speed / pressure regulated circulator configured for constant differential pressure control. No DPBV used. Design tip: keep flow resistance of common piping as low as possible.
Hydronic Zoning Options L1 120 VAC N 1. Zoning with on/off zone valves high limit / switching relay control L1 relay! contact L2 C1 circulator Wiring a 4-wire zone valve C2 B1 B2 L1 120 VAC N relay! coil T burner external! 120/24 VAC! transformer T thermostat M 4-wire zone valve thermostat M 4-wire zone valve thermostat M 4-wire zone valve
Hydronic Zoning Options 2. Zoning with on/off manifold valve actuators high flow resistance heat source 24VAC thermostats! (1 per actuator) 24VAC to/from zones pressure! regulated! circulator! hydraulic! separator manifold! valve! actuators open indicator Manifold valve actuator wire identically to 4-wire zone valves. 2 wires for 24VAC power, 2 wires for isolated end switch. 3 VA (24VAC)! heating element return spring Select a transformer by adding the inrush VA rating of all actuators, plus 5 VA safety factor. 1/8" stroke M30x1.5 threads 2 leads for power, 2 leads for isolated end switch
VENT Hydronic Zoning Options 3. Zoning with on/off circulators Each circulator has internal check valve. 12 pipe diameters of straight pipe on inlet of all circulators. zone circulators! with internal! spring checks Circulators on supply, not return Low flow resistance heat source, and short/fatʼ headers provide hydraulic separation that prevents any significant interference of circulators. Use ECM circulators set for constant speed. low flow resistance! heat source
VENT Hydronic Zoning Options 3. Zoning with on/off circulators high flow resistance heat source spring-loaded! check valves zone circulators! hydraulic! separator If boiler has high flow resistance, use a means of hydraulic separation between boiler circuit and distribution circuit.
VENT Hydronic Zoning Options 3. Zoning with on/off circulators to / from zone loads high flow resistance heat source spring-loaded! check valves zone circulators temperature! sensor! (in well) ThermoCon! buffer tank low head loss headers If boiler has high flow resistance, use a means of hydraulic separation between boiler circuit and distribution circuit.
VENT Hydronic Zoning Options 3. Zoning with on/off circulators thermostats Use one of several available multi-zone relay centers to keep wiring organized. 120 VAC! input multi-zone! relay center low voltage wiring line voltage wiring 120 VAC normally-closed priority contact L1 N DHW tank! aquastat! (A1) room! thermostat! (T2) room! thermostat! (T3) room! thermostat! (T4) room! thermostat! (T5) room! thermostat! (T6) C2 C3 C4 C5 C6 zone circulators with check valves L1 N T1 T1 T2 T2 T3 T3 T4 T4 T5 T5 T6 T6 C1 X X C1 C1 C2 C2 C3 C3 C4 C4 C5 C5 C6 C6 to boiler! high limit control DHW! tank! thermostat C1 C2 C3 C4 C5 C6 zone circulators indirect DHW tank
Hydronic Zoning Options 4. Zoning with thermostatic radiator valves sealed pressure chamber opposing spring working fluid bellows setting knob setting indicator operator mounting collar removable cartridge valve spring spindle disc tailpiece 1/2 union valve body
Hydronic Zoning Options 4. Zoning with thermostatic radiator valves
Parting thoughts... 1. Plan ahead...
Parting thoughts... 2. Keep it neat...
Parting thoughts... 3. Keep it simple...
"Best Practices in Modern Hydronic Heating - AN OVERVIEW Thank you for attending today s session... Thanks also to the planning committee, and the sponsors of this session. Please visit our website for more information (publications & software) on hydronic systems: www.hydronicpros.com