9/5/12. Emergency Thermostats Is this your override thermostat? Verify Emergency Equipment. Routine Test and Written History of Test

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1 9/5/12 Tuning your ventilation system for winter operation Thank you for participating in PorkBridge To start the presentation, advance one slide by pressing enter or the down arrow or right arrow key. Dr Mike Brumm Brumm Swine Consultancy, Inc North Mankato, MN Blog: 1 Emergency Thermostats Is this your override thermostat? 2 3 Recommendation - Heater -5 set point - Fans - +5 set point Verify Emergency Equipment Monthly 4X/yr Routine Test and Written History of Test 4 Grower negligence? 5 1

2 9/5/ They don t work if they aren t plugged in! Minimum drop 1 ft for single wide 2 ft for double-wide

3 Disaster Strikes! Dr Jay Harmon, Iowa State U Types of Heat Sensible Heat dry bulb temperature Measured with thermometer Latent Heat (evaporation) Heat involved in holding water vapor in air ~1050 BTU/lb water Cascade of Events At failure, air temperature rapidly rises As air temperature rises, ability to lose heat to air decreases - heat loss becomes latent heat Cascade of Events At failure, air temperature rapidly rises As air temperature rises, pigs ability to lose heat to air decreases - heat loss becomes latent heat Latent heat increases humidity in air Within 1 hour, 100% RH No heat loss possible by latent heat No heat loss to air at > 90 F air temp Cascade of Events With big pigs, less than 30 minutes response time lb pigs up to 1 hr response time Death is by organ failure due to heat! Some pigs live!

4 U of Illinois 15 lb pigs CO 2 within 150 minutes Ventilation Failure 50 lb pigs 60 minutes for temperature CO 2 within 95 minutes 34 F outside with NW wind 200+ lb liveweight 3 cfm/pig minimum F increase in 5 minutes How to Waste Money September and March Wean-Finish Fills single stock 2400 hd/turn Sept 1, 2006-Apr 4, ,580 gal propane 2.2 gal/pig placed = $2.64/pig ~$1.20/pig norm $6900/yr extra Bubble Wrap in Barns in Winter yes- BUT! Furnaces and Pilot Lights 1200 BTU/hr HogSlat 1200/92000 x 24 hr =.31 gal/d 0.41 gal/d AP poultry brooders Heater Offset 2 F Recommendation Temp. Room Temperature 0.35 gal/d x 30.4 d/mo = 10.6 $1.20/gal = $1.50/gal = $15.90/mo Set point Heater off Heater on Offset Differential Time 4

5 Impact of Furnace Offset on Furnace Run Time Offset Changed at Noon (Blue Vertical Line) Furnace Run Time Temperature Outside conditions - Steady temperature (34 F) with fog/drizzle 90 Controller Set Point Temperature 84 F hd Nursery Pig Wt 52 lb Set Point 71 Stg 1 50% minimum 5? cfm/pig 0.5 bandwidth motor curve Stg 2 50% minimum 8? cfm/pig 2.5 bandwidth On 73.5 Off 71 motor curve Stg 3 On 75.5 Off 73.5 Heater On 68.5 Off 71 Min/Hr F Deg Furnace ON -2.0 Furnace OFF -1.0 Variable speed pit fan ramped up after every on-cycle of the furnace. $4.50/furnace/d propane $1.20/gal propane Furnace ON -2.0 Furnace OFF -1.5 Room temperature dropped 0.5 F with lower off temperature setting. No ramping of variable speed pit fans Furnace cycling on/off = 6-7F temperature swings Preventing Overshoot Nursery Pig Wt 52 Set Point 71 Stg 1 50% minimum cfm/pig 0.5 bandwidth motor curve Stg 2 50% minimum cfm/pig 2.5 bandwidth On 73.5 Off 71 motor curve Daily high temperatures should never be at or above temperature at which variable speed fans increase speed when operating in furnace mode. Use controller to log hi/ low temps 26 Stg 3 On 75.5 Off 73.5 Heater On 68.5 Off If a furnace(s) needs to run more than 50% of the time, it isn t big enough and should be replaced with a larger unit(s). Variable Output Furnaces LB White Guardian PSI True or False? A furnace is big enough if it shuts off on the coldest day of the year! The longer the furnace runs per burn cycle, the more uniform the heat distribution in the air space!

6 Get furnaces ready for winter Propane Leaks High pressure test propane lines yearly Common ventilation mistakes related to inlets Rule of Thumb Goal: 800 to 1000 fpm Each 0.01 change in static pressure changes the throw from a ceiling inlet 2 ft

7 Inlet velocity of 1150 fpm with curtain closed what should it be? Causes? Types of Ceiling Inlets Doing the math CFM=Velocity (fpm) x Area (ft 2 ) Powered Inlets Weighted Inlets Wean-Finish or Grow-Finish Barn 2 24 stage 1 50% 6000 cfm = 800 fpm x 7.5 ft cfm/800 fpm = 7.5 ft 2 38 Velocity Inlets 39 Powered Inlets If recalibrate automatically do it in the afternoon vs early morning icing may be an issue If control problems Double loop the cable so run time per move doubles can the actuator move 2x further? Attic Air Intake Port of entry for fresh air Must be effective opening Watch for: Width of eave opening Rafter clearance over the stud wall Insulation stops Rafter construction

8 Insulation Stops Affect Inlet Area = 4 inlet to attic Attic Opening Needed Attic air intake (sq. ft.) = total hot- weather ventilation (cfm)/400 fpm Said another way Provide 1 square foot of opening for every 400 cfm of airflow Example: 6 24 fans in curtain barn 36,000 cfm/400 fpm = 90 sq. ft. of opening Assume 1,000 head building, 200 ft long 90 sqft/200 ln ft = 0.45 ft Need 5.4 eave if one side, 2.7 if two sides Attic Opening Needed Rule of thumb 6 of eave inlet per room for 40 or 50 wide tunnel or curtain barns. Questionable Air Intake NO Question This is WRONG Eave inlet mistakes Eave inlet mistakes

9 9/5/12 Eave inlet mistakes 48 Eave inlet mistakes 49 Eave inlet mistakes Ridge Vents: Inlet or Outlet? 10 mph = 0.05 in. w.g. 20 mph = 0.20 in. w.g Do you need ridge vents? Pit lids not tight 2 x 4 ft x 4 lids = 2.7 ft pit If yes how many? 7.5 ft2 total inlet

10 9/5/12 Pit lids not tight 54 Pit lids not tight 55 Fan Transition from Pit Is it a Restriction? Keep Transitions Clear Very High Static Pressure Loss 10

11 9/5/12 Pit Fan Transition after Pit Foaming Dirty Fans and Shutters 1/8 inch of dirt/dust can cause up to a 40% reduction in fan and shutter air flow

12 9/5/12 Clean Pit Fans and Shutters What s the performance of this fan? Curtain Leakage 6000 cfm/1200 hd room (stage 1 at 50% with 2 24 fans) 6000 cfm/800 fpm = 7.5 sq ft 6 x 6 hole =.25 sq ft = 3.3% Note shutter partially closed No wind, 0.06 static pressure 5 holes = 17% of inlet requirement Rodent Damage 70 Curtain Holes 71 12

13 9/5/12 Foaming Pits 72 Slide courtesy Dr Dave Schmidt, UMN Foaming Pits Pits often foam with pigs in barn Pig manure and urine tend to keep foam below slats Only a few reports of foam in the pig pen with pigs in the barn Foam above the slats when no pigs 75 Foaming Pits Explosions Empty barns or rooms Often knock down foam and then start furnace to pre- warm 2 reports of welding in empty barn catching pits on fire 77 Slides courtesy Dr Dave Schmidt, UMN and Dave Preisler, MPPA 13

14 Slide courtesy Matt Roberts, U of Illinois Slide courtesy Matt Roberts, U of Illinois Slide courtesy Matt Roberts, U of Illinois Slide courtesy Matt Roberts, U of Illinois Pit Fan Transition after Pit Foaming Lots of Theories MN, IA and IL have most reports They also have the most barns with pits How have diets changed Is it DDGS? Is it corn? More this year due to temperature? Some evidence of grower group differences 14

15 What should producers do? NEVER agitate without pit ventilation Turn OFF pilot lights when agitating What will knock down foam? Sprinklers be sure fans are ON and pilot lights OFF Diesel Fuel NO Crop Oil -?? Copper Sulfate solution 2 lb/1000 gal can t do every year Cu binds to soil Not 100% effective Yucca extracts? Silicone based anti-foam agents? Minnesota December 27, 2009 What to do if your barn didn t fail Check for cracked members, bowed bracing, nail plates that are loose, etc Cannot assess gusset plates visually If problems, consult a structural engineer Source Dr Jay Harmon, ISU Anonymous The quickest way to become an old dog. Is to stop learning new tricks Tuning your ventilation system for winter operation Dr Mike Brumm Brumm Swine Consultancy, Inc North Mankato, MN mbrumm@hickorytech.net Blog: