McQuay E-F5, Руководство по установке и обслуживанию

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McQuay IM 900 7
Operation and Maintenance
Blowing-Out Coils
1
Isolate the coil from the rest of the system by closing the
valves on both the supply and return lines (see gate valves
in Figure 5 and Figure 6).
2
Drain the coil by opening all drain valves and/or the drain
plug. Remove the vent plug to aid the draining process.
3
Once the coil has been fully drained, the blower
compressed air 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.
4
Close the vent or drain plug on the header that the blower is
connected and open the drain valve or cap on the other
header.
5
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.
6
Let the coil stand for several minutes then blow it out
again. If water comes out, repeat the blowout operation.
7
Leave all plugs out and drains open until the threat of
freezing has passed.
Figure 6: Horizontal Air Flow
Figure 7: Vertical Air Flow
Freeze Protection Fittings
During the winter, chilled water coils need to be protected
against freezing. Factory installed and tested freeze protection
fittings are brazed onto water and steam coil headers, return
bends and tube stubs (as necessary) as part of the factory
assembly process. Freeze relief caps are then screwed onto
each fitting. All coils are leak tested at 315 psi air pressure
before shipping. The relief caps are designed to burst at 650
psig, relieving pressure before coil damage occurs. When
freeze damage occurs, simply unscrew the ruptured relief caps
and screw in replacement caps.
Figure 8: Freeze Protection Fittings
DANGER
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 will result in damage
to the equipment and serious injury.
Supply
Gate
Valve
Return
Side Vent
Plug
Air Vent
Side Drain Plug
Air Flow
Union
Drain Valve
Cap
Dirt Leg
Tee