Carrier AERO 39MN Installation, Start-Up And Service Instructions Manual page 82

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* When end of supply main, see Fig. 64.
NOTES:
1. Flange or union is located to facilitate coil removal.
2. Flash trap may be used if pressure differential between steam
and condensate return exceeds 5 psi.
3. When a bypass with control is required.
4. Dirt leg may be replaced with a strainer. If so, tee on drop can
be replaced by a reducing ell.
5. The petcock is not necessary with a bucket trap or any trap
which has provision for passing air. The great majority of high
or medium pressure returns end in hot wells or deaerators
which vent the air.
Fig. 63 — Low, Medium or
High Pressure Coil Piping
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NOTES:
1. A bypass is necessary around trap and valves when continu-
ous operation is necessary.
2. Bypass to be the same size as trap orifice but never less than
1
/ inch.
2
Fig. 64 — Dripping Steam Supply to
Condensate Return
* Refer to Fig. 64 when dripping steam supply main to condensate
return.
NOTES:
1. Flange or union is located to facilitate coil removal.
2. When a bypass with control is required.
3. Flash trap can be used if pressure differential between supply and
condensate return exceeds 5 psi.
4. Coils with different pressure drops require individual traps. This is
often caused by varying air velocities across the coil bank.
5. Dirt leg may be replaced with a strainer. If so, tee on drop can be
replaced by a reducing ell.
6. The petcock is not necessary with a bucket trap or any trap which
has provision for passing air. The great majority of high pressure
return mains terminate in hot wells or deaerators which vent the
air.
Fig. 65 — Multiple Coil High Pressure Piping
* Refer to Fig. 64 when dripping supply to return.
NOTES:
1. Flange or union is located to facilitate coil removal.
2. When control valve is omitted on multiple coils in parallel air flow.
3. When a bypass with control is required.
4. Coils with different pressure drops require individual traps. This
is often caused by varying air velocities across the coil bank.
Fig. 66 — Multiple Coil Low Pressure
Piping Gravity Return
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