Desert Aire SelectAire Plus SP Series, Инструкция по установке и эксплуатации, Страница: 72 / 110

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Desert Aire - SP Manual
3.5.5 Auxiliary Heater – Hot Water Coil Maintenance
General
• Periodic inspection of the coil for signs of corrosion and/or leaks is recommended. Repair
and replacement of the coil and the connection of piping, valves, etc., should be performed
as needed by a qualified technician.
• Should the coil surface need cleaning, caution must be exercised in selecting the cleaning
solution as well as the cleaning equipment. Improper selection can result in damage to the
coil and/or health hazards. Clean the coil from the leaving air-side so that foreign material
will be washed out of the coil rather than pushed further in. Be sure to carefully read and
follow the manufacturer’s recommendations before using a cleaning fluid.
• The circulated fluid must be free of sediment, corrosive products and biological
contaminants. Periodic testing of the fluid followed by any necessary corrective measures
along with maintaining proper fluid velocities and filtering of the fluid will help to satisfy this
goal.
• If automatic air vents are not utilized, periodic venting of the coil is recommended to
remove accumulated air. Caution should be exercised to avoid injury. High pressure and/or
high temperature fluids can cause serious injury.
Blowing-Out Coils
• Isolate the coil from the rest of the system by closing the valves on both the supply and
return.
• Drain the coil by opening all drain valves and/or the drain plug. Remove the vent plug to
aid the draining process.
• Once the coil has been fully drained, the blower can be hooked up. Caps installed in the
piping on straight runs going to the supply and return connections are ideal points to
hook-up the blower. The air vent and drain plug are not suitable locations for hooking-up
the blower. Caution should be exercised when installing the blower. The blower operator
must take precautions to insure that water does not come into contact with any of the
electrical components of the blower. Failure to do so may result in damage to the
equipment and serious injury.
• Close the vent or drain plug on the header which the blower is connected and open the
drain valve or cap on the other header.
• Operate the blower for 45 minutes and then check the coil to see if it is dry. A mirror placed
in the discharge will become fogged if moisture is present. Repeat this procedure until the
coil is dry.
• Let the coil stand for several minutes then blow it out again. If water comes out, repeat the
blowing operation.
• Leave all plugs out of the drains open until the threat of freezing has passed.
Flushing Coils
• We recommend the use of inhibited glycol designed for HVAC applications for corrosion
protection. The use of uninhibited glycol has produced formicary corrosion in copper
tubing. The complete filling of water coils with an inhibited glycol solution for freeze
protection can be expensive. In some instances, it is more cost effective to flush the coils