Poultry House Heating Systems. Forced air furnaces. They all can work. Forced air furnaces

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1 Poultry House Heating Systems There are primarily six heating systems used in poultry houses today: Forced air furnaces Conventional brooders Radiant brooders Radiant tube heaters High intensity radiant heaters Alternative heating systems Michael Czarick The University of Georgia They all can work But there are significant differences as to how they heat a house. As a result they need to be installed and managed differently. Forced air furnaces Forced air furnaces Most simplistic type of heating system where% of heat produced is the form of very hot air Since the hot air is significantly lighter than the rest of the air in the house it quickly rises to the ceiling leaving coolest air next to the floor..0 F 75.0 F How much of a problem is stratification with forced air furnaces? During brooding air temperature increases approximately one to three degrees per foot as you move towards the ceiling. 1

2 Stratification (1 o F per foot) Stratification (2 o F per foot) F F F 65.0 F Stratification (3 o F per foot) Stratification can be further magnified if there is leakage.0 F In general, the cooler the weather, the longer the furnaces operate, the greater the amount of stratification 65.0 F Thermocline Thermocline.0 F.6.0 F F 75.0 F 2

3 Half house curtain leakage can also lead to thermocline formation Circulation fans are a must in houses with forced air furnaces! F Must move the hot air down to bird level 75 Furnaces are best suited for house with: Low ceilings And should be avoided in high ceiling houses High ceiling house using furnaces (cloud of hot air collecting near the ceiling) In low ceiling houses the hot is trapped near the floor.0.0 F.0 F

4 Hot air flow pattern in low ceiling house.0 F Best suited for: Totally enclosed tight houses Best suited for: Totally enclosed tight houses Or with older birds where maintaining a proper floor temperature is not as crucial But, furnaces can still be problematic (turkey breeder house with furnaces) Advantages: Relatively low initial cost per Btu produced Few heating units required Installation Maintenance No pilot lights Disadvantages: Inefficient floor heating. Ceiling heating system Relatively low energy efficiency To obtain floor temperatures in the low to s air temps have to be in the mid to high s. Uniform floor temperatures 4

5 Floor temperatures.0 F.0 F Floor temperature histogram % F Birds cannot self thermo-regulate Conventional pancake brooders Conventional pancake brooders produce two forms of heat Hot air like furnaces Conventional pancake brooders produce two forms of heat The hot air tends to increase room air temperature.0 F Radiant heat 5

6 The radiant heat warms the floor near the brooder above air temperature.0 F The radiant heat warms the floor near the brooder above air temperature.0 F How much the floor is warmed depends to a large extent on proximity The closer to the brooder, the greater the amount of floor heating The floor heating profile can be fairly dramatic.0 F Degrees above air temperature Distance from brooder (ft) F Conventional brooder-benefits Chicks can seek their own comfort zone F 120 A variety of floor temperatures from which the birds can choose F F 6

7 Conventional brooder-benefits Chicks can seek their own comfort zone Air temperatures can drop below ideal without necessarily adversely affecting bird performance. House temperature o F.0 F F Brooder rings are often used in turkey housing to keep poults near heat source Cold room brooding 96.0 F.0 F Cold room brooding Conventional brooder-benefits Chicks can seek their own comfort zone Air temperatures can drop below ideal without necessarily adversely affecting bird performance. Drafts can occur and birds will not be harmed as much as houses with forced air furnaces. 7

8 Radiant heat and drafts Drafts in house with brooders.0 F 68.0 F Birds gathering near brooders in drafty house Birds gathering near brooders in drafty house.0 F F Draft in furnace house.0 F Conventional brooder-benefits Brooders are much better suited for producers with older, looser houses or poor managers than are furnaces F 8

9 LI01 Conventional brooder - weaknesses Relatively small floor area covered per brooder, which results in a large number of brooders Especially in today s larger houses.0 F How much floor area is heated (radiant heated) by a single conventional brooder? Area = 3.14 X R 2.0 F LI F 65.0 F Floor heat profile of a conventional brooder F.0 F 65.0 F How much floor area is heated by a single conventional brooder? Area = 3.14 X R 2 = 3.14 X 5 2 = 3.14 X 25 ft 2 = ft 2 (approximately) How many conventional brooders should be installed in a house? For a curtain-sided house we need somewhere around 500,000 Btu s of heat in 40 X 250 brooding area. # Brooders = 17 (500,000/30,000) We typically install somewhere around 24 Why is this? Advantages of having a surplus of brooders: More floor area receiving radiant heat 24 in a 40 X 250 brood area approximately 20% of the floor area would receive some amount of radiant heating. With 17 conventional brooders only 14% of the floor would be receiving a significant amount of radiant heat. Birds are never that far from radiant heat source Safety factor Protects from floor overheating 9

10 Conventional brooders Large number of brooders Conventional brooders Fewer brooders Conventional brooder placement Conventional brooder placement Near feed and water Encourages chicks to feed and water Conventional brooder placement Near feed and water Near side wall Offsets radiant heat loss from curtain Radiant heat gain from curtain When the sun hits a curtain, it is often heated well above air temperature. The hot curtain surface radiates heat to the floor near the side walls. 10

11 Warm curtain Warm, south facing curtain on a cold day. (40 o F outside) F F Radiant heat loss from curtain If the curtain is colder than the floor, the floor heats the curtain, which lowers the temperature of the floor. Floor temperatures in furnace house.0 F LI01.0 F Floor temperature profile F 94 Warm, south facing curtain on a cold day. (40 o F outside) F F 11

12 Cold, north facing curtain on cold day. (40 o F outside) Southern side wall (40 o F outside) F.0 F F 60.0 F Northern side wall (40 o F outside) Pancake brooders near the side walls can help offset radiant heat loss from the curtains.0 F.0 F F Conventional brooders placement Near feed and water Near side wall Offsets radiant heat loss from curtain Close to leakage Draft in house with brooders.0 F 12

13 Curtain leakage.0 F Conventional brooders placement Near feed and water Near side wall Offsets radiant heat loss from curtain Close to leakage Last but not least, promotes litter drying 50.0 F 55.0 F 60.0 F 65.0 F Most moisture is added in the vicinity of the feeder/drinker lines Conventional brooders summary Advantages over furnaces: radiant heat better bird performance Disadvantages over furnaces: relatively large number need because of relatively small heating zone Initial cost Maintenance Control How can we reduce the number of brooders required? Increase the amount of floor are covered by each brooder Increase the size of the radiant element Larger emitting surface tends to produce more radiant heat in in 2 13

14 Radiant brooders Since they produce significantly more radiant heat the need to be installed higher above floor to it over a larger area. Degrees Above Ambient (F) Radiant heat profile comparison Radiant Brooder Pancake Brooder Distance From Brooder (ft) Floor temperature profile.0 F Floor temperature profile F LI F Floor temperature profile.0 F Floor temperature profile F 105 LI01.0 F 14

15 LI01.0 F 60.0 F Floor temperatures in house with radiant brooders prior to chick placement AR01.0 F.0 F Histogram of floor temperatures F How large of an area does a radiant brooder heat?.0 F Radiant brooder floor temperature profile F LI F 65 Radiant heat zone radius approximately 8 How large of an area does a radiant brooder heat? Area = 3.14 X R 2 = 3.14 X 8 2 = 3.14 X 64 ft 2 = 200 ft 2 (approximately twice that of a conv. brooder) How many radiant brooders should you install? Based on heat demand a 40 X 250 brood area, curtainsided house requires approximately 500,000 Btu s/hr of heat. Radiant brooder produces approximately 40,000 Btu s/hr of heat 500,000 / 40,000 = 12 15

16 How much of the floor is receiving radiant heat? General radiant brooder specifications Coverage area of 12 conventional brooders coverage area = 200 ft 2 X 12 = 2,400 ft 2 Percentage of brooding area covered with radiant heat % = 2,400 ft 2 / 10,000 ft 2 = 24% No surplus of heating capacity/safety margin Approximately one for every 750 square feet of floor space (brooding end) Approximately one for every 1,200 square feet of floor space (nonbrooding end) Using this guideline how much of the floor is receiving some level of radiant heating? Coverage area of 14 conventional brooders (approximately one per 750 ft 2 ) Coverage area = 200 ft 2 X 14 = 2,0 ft 2 Percentage of brooding area covered with significant amount of radiant heat: % = 2,0 ft 2 / 10,000 ft 2 = 28% Does a totally enclosed house require fewer radiant brooders? 40 X 250 brood area, curtain-sided house approximately 40% less Btu s/hr 300,000 Btu s/hr Radiant brooder produces approximately 40,000 Btu s/hr of heat 300,000 / 40,000 = 8 Totally enclosed housing with fewer radiant brooders Minimal coverage area (16%) With high minimum ventilation rates a totally enclosed house can have the same heating demand as a curtainsided house. Just because a house has more brooders doesn t mean it will use more gas. Advantages over conventional brooders Fewer needed Less maintenance No pilot lights 16

17 Pilot lights A pilot light produces about 1,200 Btu s/hr of heat Gallons = 1,200/92,000 = gallons/hour Gallons per day per 26 brooders Gallons = X 26 brooders X 24 hrs = 8.1 gallons per day Using 14 radiant brooders with spark ignition would save a producer approximately gallons $2/gal) over a ten day period. Radiant brooder placement Radiant brooder placement Same as conventional brooders for the same reasons Radiant brooder placement Two rows staggered With pairs in the ends to add a little extra radiant heat where it tends to be needed most More floor heating near cool side walls Helps to compensate for tunnel curtain leakage.0 F.0 F.0 F 65.0 F.0 F 17

18 Tunnel curtain leakage Helps to compensate for half house curtain leakage.0 F.0 F.0 F 65.0 F Offsets ½ house curtain leakage Helps to compensate for end door leakage.0 F.0 F 65.0 F 65.0 F Nonbrooding end radiant brooder placement Most houses don t have sufficient radiant brooders on nonbrooding end Minimum of 65% of what is installed on brooding end 65.0 F 12 radiant brooders 5 radiant brooders, 4 operational 65.0 F 18

19 Back ½ of non brood end Radiant brooder placement If an insufficient number of radiant brooders are installed, placing them over feed and water can lead to very high floor temperatures under the brooders F 65.0 F 65.0 F Radiant brooder placement Radiant brooder overheating caused by not installing a sufficient number of radiant brooders. Radiant brooder placement Which has lead some to install radiant brooders down center of house Brooders down the center can still be problematic even in totally enclosed houses To be effective..0 F.0 F.0 F Sensor should be placed near side wall Circulation should be used 19

20 LI F F What s wrong with this picture? Radiant brooder too low F 120 LI01.0 F Very steep temperature gradient F How can we reduce the number required even further? Increase the size of the radiant heat zone of the brooder even further increase the size of the radiant element even more. 120 Radiant tube heaters Floor temperatures in house with radiant tube brooders prior to chick placement F 20

21 Floor temperature profile LI Floor temperature profile F o F variation in 35.0 F Histogram of floor temperatures F days later LI F 2 days later.0 F F 20 o F variation in F 75 LI01 20 o F gradient in 8 21

22 Pancake brooders Radiant tube heaters.0 F.0 F F.0 F 86 Percent of floor area covered by radiant heat in typical house with tube heaters? Four tube heaters in a 40 X 250 brooding area 125,000 Btu s/hr Coverage area per tube heater Approximately 30 X 50 = 1,500 square feet % coverage area = 4 X 1,500 = 6,000/(40 X 250) = 6,000/10,000 = 60% Factors affecting floor heating pattern of a tube heater.0 F F Factors affecting floor heating pattern of a tube heater summer winter Factors affecting floor heating pattern of a tube heater.0 F.0 F F F Heating system run time The less it runs the more uniform the floor temperature Level of side wall insulation 22

23 Curtain-sided house Curtain-sided house F F F 75.0 F Totally enclosed house.0 F Factors affecting floor heating pattern of a tube heater Tube length F F F F 75.0 F 75.0 F 75.0 F The longer the tube the greater the variation Tubes should be kept to a maximum of 40 Temperature variation along length of tube heater F 130 Temperature variation along tube length F F F 23

24 Resulting in an egg shaped coverage area Best way to reduce variation reduce tube length 20 long tube heater 20 tubes are the ideal, producing more of an oval/rectanglar pattern U tubes heaters can also create much more uniform floor temperatures U-Tube radiant heater 10 U-Tube radiant heater create a more circular pattern 0.0 F 0 Hot Warm Cool Warm F 24

25 Reflector design also affects floor heating pattern.0 F Reflector design A closed design A more open design.0 F Reflector design Open reflector design.0 F.0 F.0 F.0 F.0 F.0 F Reflector design Closed designs are better suited for high ceiling houses Radiant tube heaters Advantages: Large amount of floor space covered with radiant heat Fewer units to maintain Up out of the way Exhaust gases can be piped out of the house. Disadvantages Potential ceiling overheating Open designs are better suited for low ceilings and/or wider houses. 25

26 High ceiling temperatures Circulation fans F F Radiant tube heaters Radiant tube heaters in wide houses Advantages: Large amount of floor space covered with radiant heat Fewer units to maintain Up out of the way Exhaust gases can be piped out of the house. Disadvantages Potential ceiling overheating Most radiant heat is not where it is most needed the center of the house which can be problematic in loose curtain-sided houses. Can be problematic in wider houses. Radiant tube heaters can be problematic in wider houses Tube heater in a 40 open ceiling house The lower the ceiling, the wider the house, the more of a difference there will be in floor heating 26

27 Tube heater in a 40 wide dropped ceiling house Radiant tubes in 40 wide.0 F.0 F Coverage width approximately 30 Coverage area in 8 ceiling..half as much coverage area Tubes in 60 wide house with 16 ceiling much wider coverage area F F 65.0 F But a tube heater in a 60 wide dropped ceiling house has the same coverage area as in a 40 wide dropped ceiling house with a 10 ceiling about 30 Radiant tube in 60 wide house F F 27

28 Radiant tubes in 60 wide house (side wall) As a result wider houses should have two rows of tubes F F Two tubes on side walls? Quick preheating of incoming air To get good floor coverage the side walls need to be relatively high High intensity radiant brooders,000 Btu s/hr ½ way between a radiant brooder and a conventional tube heater High intensity radiant brooder vs. conventional radiant brooders (50 house).0 F 50 wide house 77.0 F 28

29 Radiant brooders (back ground) HI radiant brooder (foreground) F High intensity radiant brooder Installed close to the ceiling like a radiant tube because the heat output is similar to a tube,000 vs 125,000 Btu/hr 75.0 F The first high intensity radiant brooder was the Quadratherm (CTB) Reflector designed to direct the radiant heat more outward Less of a hot spot directly underneath the brooder. Floor heating pattern of high intensity radiant brooder LI01.0 F Feed line to feed line = 40.0 F High intensity radiant brooder F Coverage area (approximately X 30 ) F 29

30 Then came the AV Heater (HH) Though the coverage area is similar between these units There are differences some differences Quadratherm AV-Heater 0.0 F F F 60.0 F Quadratherm Avheater Quadratherm Avheater 30

31 Floor heating comparison Av heater Quadratherm Then.L.B. White - Oval 20 long,000 Btu s/hr Quadratherm - Choretime 20 tube LB White (same width but about 10 longer length).0 F.0 F 31

32 Yet, other,000 Btu/hr radiant heaters Space Ray Big Foot and 20 tube Quadratherm - Choretime.0 F.0 F Bigfoot Space Ray (a little narrower a little longer) 20 Tube - Space Ray (similar width 10 longer length).0 F.0 F.0 F 75.0 F Quadratherm - Choretime Ceiling temperatures (Quadtherm vs. AV Heater).0 F 1.0 F F

33 Ceiling temperatures (Quadtherm vs. L.B. White Oval ) Ceiling temperatures (Quadtherm vs. Space Ray Big Foot) F F Ceiling temperatures (Quadtherm vs. Space Ray 20 tube) Number required to heat a broiler house? F Brooding area Approximately one per 1,500 square feet of floor space Nonbrooding end Approximately one per 2,400 square feet of floor space Installing fewer can lead to heat distribution problems as well as problems with floor overheating 40 X 500 broiler house 6 to 7 brooding end 4 to 5 nonbrooding end Percent of floor area covered by radiant heat in house with HI radiant heaters? Five tube heaters in a 40 X 250 brooding area,000 Btu s/hr Coverage area per tube heater Approximately 35 X 30 = 1,050 square feet % coverage area = 6 X 1050 = 6,300/(40 X 250) = 6,300/10,000 = 63% 33

34 H.I. brooders center of a 40 wide house vs. radiant brooders Conventional radiant brooders.0 F 6 down the center 40 X 250 brood area.0 F 75.0 F High intensity radiant brooders Side wall conditions with conventional radiant brooders 75.0 F 75.0 F Side wall conditions with high intensity radiant brooders Side wall with conventional radiant brooders 75.0 F 75.0 F 34

35 Side wall with high intensity radiant brooders Installation in wider houses 75.0 F 54 wide house installed in the center of the house Very little side wall heating.0 F.0 F F 55.0 F Two rows of radiant brooders have better overall floor coverage Two rows of radiant brooders have better overall floor coverage F.0 F 35

36 Two rows or HI radiant heaters? Two rows in 54 wide house Two rows in 54 wide house Improved side wall coverage.0 F.0 F Lastly.there are alternative heating systems There are basically two types of alternative heating systems (do not burn propane/natural gas) Hydronic - Hot water systems Hot air systems poultryventilation.com 36

37 Hydronic systems A group of houses is heated using a central boiler that burns some type of low cost fuel to heat water to a temperature of between 150 o F 200 o F: The heated water is circulated to the houses on the farm. Some type of heat exchangers are then used to heat the air/floor in the houses The slightly cooler water (-20 o F) is then returned to boiler to be heated again. Boilers themselves are fairly similar Biggest difference between these systems is the type of heat exchanger used. There are primarily four types of hydronic heat exchangers used in poultry houses Types of hot water heat exchangers: Black steel pipe Typically installed on the side walls Black steel pipe heat exchangers: Each foot of pipe is capable of adding a specific amount of heat to a house (more pipe more heat): 1 ½ black steel pipe = 150 Btu s/hr per foot 2 black steel pipe = 1 Btu s/hr per foot 1 ½ black steel pipe If you wanted to add up to 500,000 Btu s/hr of heat to a house 1 ½ black steel pipe = 150 Btu s/hr per foot 500,000/150 = 3,300 2 black steel pipe = 1 Btu s/hr per foot 500,000/1 = 2,0 Black steel pipe installed on side wall Thermal image of hot water radiator pipes on side walls Basically a hot air heating system (furnaces producing warm air) Don t produce a substantial amount of radiant heat compared to conventional/radiant brooders 2 black steel pipe 37

38 Cost? 2 black steel pipe = 1 Btu s/hr per foot 500,000/1 = 2,0 $3 per foot = $8,0 Types of hot water heat exchangers Black steel pipe Finned tube More surface area More heating produced per foot Less pipe required Finned tubes have greater surface area (approx. five times the heat output per foot) 1 ½ finned tube = 750 Btu s/hr per foot (150 bsp) 2 finned tube = 0 Btu s/hr per foot (1 bsp) Finned tubes Traditionally installed in vicinity of air inlets to warm cold incoming air. If you wanted to add up to 500,000 Btu s/hr of heat to a house 1 ½ finned tube 500,000/750 = 6 2 finned tube 500,000/0 = 5 Finned tubes on ceiling near side wall inlets Finned tubes on side wall below inlets 38

39 Finned tubes on side wall and ceiling Finned tubes install next to two way attic inlet/circulator Finned tubes installed below attic inlets Cost? 2 finned tube = 750 Btu s/hr per foot 500,000/0 = 5 $15 per foot = $8,0 ($8,0 bsp) F Types of hot water heat exchanger: Radiator with blower fan located next to ceiling Fin pipes Black steel pipe Individual radiators with blower fans Lower cost option Similar to forced air furnaces but air produced is not as hot. 39

40 Cost? Btu /hr output = 225,000 to 150,000 Btu s/hr $1,000 per unit. Types of hot water heat exchanger: Black steel pipe Finned tubes Individual radiators with blower fans Floor heating Very expensive 500,000 Btu s/hr system would require 3 possible 4 exchangers $3,000 - $4,000 Floor heating systems Concrete floor with pipes running through it Floor heating systems Concrete floor is required adding substantial cost to a house. Litter depth has to be carefully controlled because litter is a very good insulating material. Most of these systems are installed in houses that clean out after each flock. Hydronic floor heating systems.0 F.0 F Often houses with floor heating systems also have a secondary heating system Floor heating: Primarily designed to provide background heat Tends to have a very slow response time.0 F 40

41 Supplemental brooders in turkey brooding barn.0 F 75.0 F.0 F 75.0 F Often houses with floor heating systems also have an another heating system Floor heating: Primarily designed to provide background heat Tends to have a very slow response time Yes, the litter tends to be dry but this tends to be true with any hydronic system Not a very common type hydronic heating system cost.0 F 75.0 F All Hydronic systems require a substantial initial investment First, there is the boiler Fuel storage Pumps Hot water delivery system 41

42 and of course there are the heat exchangers To reduce initial cost hydronic systems tend to be total farm heating systems The boiler is the largest single cost and the cost difference between a boiler to do a single house and multiple houses is not substantially greater. To reduce initial cost hydronic systems tend to be total farm heating systems The boiler is the largest single cost and the cost difference between a boiler to do a single house and multiple houses is not substantially greater. In some areas of the country the entire farm (poultry houses, dwelling houses, farm shop, etc) is heated using a single boiler. 1.4 million Btu s/hr Hot air systems Each house has its own heating unit that burns some type of low cost fuel: Air is drawn from the house, Runs over the burning chamber/heat exchanger, Returned to the house where it is distributed using either duct system and/or circulation fans Combustion air flow through heating unit 42

43 House air flow through heating unit House from air flowing into and out of heating unit Primarily two types of hot air distribution systems Rigid duct system Rigid duct system Perforated plastic duct 43

44 Perforated plastic duct ran the length of the house Short duct with circulation fans Circulation fan distribution system Circulation fans moving heated air towards the brooding end wall. Circulation fans moving heated air towards the brooding curtain Circulation fan in half house curtain to move heated air to nonbrooding end 44

45 Alternative heating systems There are a number of benefits associated with these system but they can come with very high initial cost. poultryventilation.com 45