Types of Heaters Steam Quaker Oats St. Joseph, MO

Steam Heaters n Why use steam heaters n How they work n Types of steam unit heaters n Advantages/disadvantages n Start-up process for steam heating n Process during heat treatment n Post heat treatment follow-up procedures

n Why use steam heaters n How they work n Types of steam unit heaters n Advantages/disadvantages n Start-up process for steam heating n Process during heat treatment n Post heat treatment follow-up procedures Steam Heaters

n Boiler in place n Boiler capacity n Heaters already in place Why Heat Treat with Steam????

How Steam Heaters Work... n Coils, fans, housing, dampers, traps, strainer, check valve, thermostats, etc. n Coils are heated by steam passing through them n Air is heated as fan pulls air up through heated coils n Fans aid in dispersion of heated air throughout area To decrease heat: open damper To decrease heat: open damper To increase heat: close damper To increase heat: close damper

Types of Steam Heaters n Portable units n Fixed units Ceiling mounted Ceiling mounted Floor mounted Floor mounted

Portable Steam Heaters n Advantages Can be used in areas where heat is slow to rise Can be used in areas where heat is slow to rise Can be moved around where needed Can be moved around where needed Easy to clean and maintain Easy to clean and maintain n Disadvantages Additional storage area Additional storage area May get lost May get lost

Fixed Steam Heaters n Ceiling mounted heaters Maintain floor space Maintain floor space Smaller, considered space savers Smaller, considered space savers Do not get damaged as easy Do not get damaged as easy Harder to access for cleaning and maintenance Harder to access for cleaning and maintenance Ability to direct heat in all directions Ability to direct heat in all directions

Fixed Steam Heaters n Floor mounted heaters More heat at floor level initially More heat at floor level initially Easier to clean and maintain Easier to clean and maintain Get damaged more easily Get damaged more easily Generally larger than ceiling mounted units Generally larger than ceiling mounted units Ability to shoot heated air in all directions Ability to shoot heated air in all directions

Advantages of Steam Heaters n Hotter heat n Better control of steam heat if heaters are working properly Open dampers if area gets overheated Open dampers if area gets overheated Close dampers if area needs more heat Close dampers if area needs more heat n Cheaper than gas/electric n Steam provides much of the humidity (30-50%) necessary for wooden equipment (sifter boxes) n Safer than gas fired/electric heaters

Disadvantages of Steam Heaters... n Boiler capacity-necessary steam pressure n Coils must be clean so they will heat efficiently n Maintenance of traps, steam pipes, valves, couplers, fans, motors, etc. n Employee safety concerns: burns n System may become water logged resulting in slow or ineffective heat-up

Quaker Oats - St. Joseph, MO n Goal: Core temperature 130°F / 30 hrs n 6 heat-ups/year Mar, May, July, Aug, Oct, Nov Mar, May, July, Aug, Oct, Nov n Heat 3.5 million cubic feet n steam heaters various sizes various sizes ceiling/floor mounted units ceiling/floor mounted units n 3 gas fired heaters n Departmental prep checklists n Post heat follow-up procedures

Pre-Heat Treatment Checklist For Steam Heating… – 2 week inspection prior to heat inspect fan motors on heaters inspect fan motors on heaters check couplers check couplers inspect coils inspect coils check traps check traps repair steam leaks repair steam leaks inspect unit heater coils inspect unit heater coils inspect condensate return lines inspect condensate return lines ensure system is ready for heat treatment ensure system is ready for heat treatment

Pre-Heat Treatment Checklist For Steam Heating... n Day of heat treatment Increase boiler pressure to maximum capacity (25,000-30,000 pounds) Increase boiler pressure to maximum capacity (25,000-30,000 pounds) Set all heaters to manual mode Set all heaters to manual mode Set thermostats on unit heaters at 140°F Set thermostats on unit heaters at 140°F Ensure steam valves and return lines are open at heaters Ensure steam valves and return lines are open at heaters

Pre-Heat Treatment Checklist For Steam Heating cont... Turn on main header valves to get steam to unit heaters Turn on main header valves to get steam to unit heaters Heat unit heater coils Heat unit heater coils Turn fans on to unit heaters Turn fans on to unit heaters Set out thermometers Set out thermometers

Steam Heaters During Heat-Up... n Auto vs. manual mode Heaters started in manual mode Heaters started in manual mode Once temperatures heat up, positioned in auto mode if thermostats are working Once temperatures heat up, positioned in auto mode if thermostats are working n 3 pipefitters per shift to monitor heat progress Temperature readings every two hours Temperature readings every two hours Maintain 130°F for 30 hours Maintain 130°F for 30 hours Making repairs as necessary Making repairs as necessary

Steam Heaters During Heat-Up... n Slow Heat-Up system may be waterlogged system may be waterlogged – check condensate return line – ensure steam valves are open – waterlogging will cause slow heat in all areas ensure fan on heater is running if area(s) are cool ensure fan on heater is running if area(s) are cool check unit heater coils for buildup if area(s) are cool check unit heater coils for buildup if area(s) are cool ensure openings to outside are closed ensure openings to outside are closed

Steam Heaters During Heat-Up... n Fast Heat-Up use auto mode to shut heat off at desired temperatures use auto mode to shut heat off at desired temperatures open up dampers with fan running open up dampers with fan running throttle steam back at heaters throttle steam back at heaters shut heater fan off shut heater fan off reduce steam pressure if fast heat-up is noted in all areas reduce steam pressure if fast heat-up is noted in all areas

Other Factors Affecting Heat Treatment Success... n Wind n Outside temperature n Rain n Openings to outside not properly sealed n Knowledge and/or preferences of pipefitters/maintenance personnel running the heat treatment

Post Heat Follow-Up Includes... n Determine shutdown time n Shut boiler down two hours prior n Coast 2 hours pickup thermometers pickup thermometers shut off header valves / unit heater valves shut off header valves / unit heater valves leave fans running for circulation leave fans running for circulation n Departments open up for cool down **********