Prepare Poultry Houses for Cooler Weather
It's not too late to ensure poultry houses are prepared to withstand the worst of the winter weather. Tips from Dr Tom Tabler (Extension Professor), Jessica Wells (Extension Instructor) and Dr Wei Zhai (Assistant Extension/Research Professor) in the Poultry Science Department at Mississippi State University.When summer begins to wind down, Mississippi
poultry growers should prepare their
houses for the cooler weather ahead. Gas prices
continue to increase, and growers must get the
most out of every dollar spent on fuel. This
means houses and equipment must be at peak
performance.
Routine maintenance is critical to keeping
houses operating efficiently. Poultry houses
and the equipment inside have to last for many
years. This will only happen if the houses and
equipment are well taken care of with regular
maintenance.
Without question, the top maintenance
priority heading into colder weather is house
tightness. Tightness is important throughout the
year for proper environmental control, but it is
critical during winter to minimize air leaks and
reduce fuel use. Air leaks increase fuel consumption
and have a detrimental effect on bird
performance. Chicks easily become chilled from
air leaks around footings, loose curtains, and
end doors and may never recover. Performance
may suffer throughout the flock because of poor
environmental conditions.
Fuel costs may also be excessive. A crack as
small as one-eighth of an inch along both sides
of a 500-foot house is equivalent to more than a
10-square-foot hole in the wall. Make sure end
doors and footings are sealed to prevent air
leaks. The only air that enters your house should
be the minimum ventilation air, and it should
enter through the vent doors, not loose curtains,
footings, or end doors.
Curtains must be tight with flaps in place
and should properly seal at the bottom. Broken
strings should be replaced to prevent curtains
from sagging. It is impossible to have a tight seal
at the top if curtain strings are broken. Tunnel
curtains require special attention. They are usually
insulated and, therefore, heavier than regular
sidewall curtains. They may snag or hang
up at either end of the cool cell when closing, preventing a proper seal at the corners; and the
extra weight adds increased tension on strings,
causing them to break more often.
If your houses have tunnel doors instead of
tunnel curtains, they should seal snugly in front
of the cool cells. If houses have a drop ceiling,
there should be no holes in the vapor barrier
that will allow warm air to escape into the attic.
This wastes fuel and allows condensation to
form in the attic, reducing the effectiveness of
loose fill insulation.
Vent doors should be checked regularly to
verify they open and close properly and seal
tightly when closed. Vent door strings often
work loose from the steel rod that opens and
closes the doors when the vent machine runs.
Vent machines may run thousands of times on
a winter batch of birds. These machines have
gears and grease fittings under the cover that
protect the gears from much of the dust and dirt
in the chicken house environment. Do not forget
the fittings need grease from time to time to
work properly.
Regularly test house static pressure (difference
in air pressure between inside and outside
the house) to determine tightness. Static pressure
can be tested by closing all vents, fan shutters,
end doors, and so forth before turning on
one tunnel fan and then reading the static pressure
from the house controller. A curtain-sided
house should be able to pull at least a 0.12 static
pressure (0.20 and higher is common and often
a minimum on solid sidewall houses); otherwise,
proper minimum ventilation will be hard
to achieve. A high static pressure is necessary to
adequately mix and warm cold incoming air before
it falls to the floor and chills birds. Improper
mixing can affect temperature sensors, resulting
in greater fuel usage, and it may be detrimental
to bird health.
Temperature sensor placement is critical to
bird comfort. Years ago, it seemed that almost
everyone hung the one temperature sensor for the entire house maybe 50 feet from the brood end wall
and about 3 feet off the floor (even though chickens
were on the floor!). Today, in a single house, it is common
to have multiple sensors that remain at approximately
bird level, regardless of bird age. Often these
sensors are attached to a water line cable and raised
with the water line as the birds grow. This ensures the
sensors always remain at approximately bird height
throughout the flock.
Each sensor controls only the temperature in the
designated “zone” where the sensor is located. This
way, if one zone is cool and all other zones are satisfied,
only heating units in the cool zone will run,
thereby maintaining house environment as efficiently
as possible. Having sensors at bird level guarantees the
proper temperature is maintained at bird level.
Sensors collect a thick coating of dust and dirt during
summer when cool cells and tunnel fans are operating.
These sensors need to be cleaned before winter.
Another priority is sufficient gas pressure to
operate brooders and furnaces. Brooders and furnaces
are designed to operate most efficiently at a specific
pressure. Forced-air furnaces require a higher operating
pressure than brooders. (When high efficiency
infrared brooders are used, many integrators no longer
require gas furnaces in new construction or remodeling
projects.) A gas pressure problem is generally most
noticeable at the farthest distance from the propane
tank. If tanks are at the middle of the house, brooders/
furnaces at either end will be the first to act up. When
pressure is too low, heating units will only produce a
weak, yellow flame (providing little heat) instead of the
strong blue flame associated with normal operation.
Forced-air furnaces will show a problem before
brooders because of their higher pressure demand, but
brooders can have the same problem if pressure is low
enough. While the problem is often associated with too
little gas in the tanks, undersized piping inside and/or
outside the chicken house also can cause it, especially
if you have recently remodelled and added additional
brooders/furnaces without changing piping.
Do not forget about gas leaks. Sometimes you can
smell a leak because of the chemical added for just that
purpose. However, you can also take a spray bottle of
soapy water and spray on pipe joints, regulators, and other parts, and look for bubbles that will indicate
leaks that perhaps you did not smell.
Remember there are differences in operating
pressure between propane and natural gas systems.
Propane units often operate on 10 to 12 inches of
water column while natural gas units operate on 6 to 8
inches. Your gas provider should be able to test regulators
on your farm to make sure you have adequate
pressure settings.
Also, brooder orifices match the type of gas you
are using (propane or natural). If you switch from propane
to natural gas, you will have to change orifices in
all your heating units. Check your orifices (both pilot,
if so equipped, and burner) going into cooler weather
to make sure they are not clogged with dust, dirt,
spider webs, mud daubers, and so forth after a long,
hot summer. The reason a brooder fails to ignite may
not be a lack of gas, inadequate pressure, or a faulty
igniter, but simply a clogged orifice. If you have direct
spark brooders without pilot lights, keep a few spare
igniters on hand just to be safe.
Fans are critical to any minimum ventilation program.
Fans and shutters must be kept clean to operate
properly. They should be washed between flocks to
maintain optimum efficiency. Belts must be tight for
fans to operate at their best. Belts that squeal and slip
or have excessive play or wobble should be changed.
Belt drive fans also have bearings that must be greased
occasionally.
Stir fans may be an option to consider if you do
not have them. Stir fans can help reduce temperature
stratification by moving hot air off the ceiling. This can
help increase moisture removal from the litter.
Fans not used for minimum ventilation (i.e. tunnel
fans) should be covered during winter to prevent air
leakage around shutters and cones. Covers must be
able to blow off as needed to reduce heat buildup or in
case of an emergency.
Don’t wait until cold weather arrives to take action.
Start early and you’ll be prepared for the cooler
weather ahead. Routine maintenance will result in
energy savings and keep your operation running
smoothly and efficiently.
December 2012