Carrier 39LC, 39LB, 39LD, 39LA, 39LE, 39LF, 39LH03-25, 39LG specifications Changing Coil Hand

				LEGEND
1	—	Accessory Side Panel	5	— Baffle Angle Screw
2	—	Left Side Panel	6	— Piping
3	—	Inside Baffles	7	—	Right Side Panel
4	—	Top Panels	8	—	Baffle Screw

Fig. 41 — Horizontal or Vertical Unit — Vertical Coil Removal (39LB,LC,LF,LH Units)

Changing Coil Hand

NOTE: Electric heat coil hand cannot be changed.

NOTE: The coil cover panel is not part of the coil. Remove cover panel from end of unit. New holes must be cut in coil cover panel. Original holes must be plugged and insulated. New side panels may be necessary when changing coil hand.

NU-FIN COILS — The NuFin coil is airflow direction sensi- tive, especially when used in dehumidifying applications. Hydronic versions are counterflow circuited for full gravity draining when installed level.

Correct installation will result in the typical bottom inlet on leaving air face and top outlet on entering air face of coil, a self-venting design. This will ensure cold air contact with cold water, and warm air with hot water.

Coil repositioning for opposite hand application will com- promise one or more of these characteristics. However, there will be those situations where this may prove acceptable.

As a general rule, a change from counterflow circuiting to parallel flow for sensible heating and cooling applications will result in a 5% drop in net capacity per row of coil. In one and two row heating coils, the actual drop may not be measurable, thus of insignificant consequence.

It is important that the airflow direction of the NuFin coil be adhered to when latent cooling is possible. Significant moisture carryover from the face of the dehumidifying coil will result if this rule is violated, even at very low face velocities. The same

result is often experienced if after-market fin coatings are applied.

If a NuFin hydronic coil is installed with correct airflow, but opposite piping hand, and counterflow is maintained, steps must be taken to ensure that the coil is continuously vented, and that the water velocity is maintained to prevent the coil from air-binding.

Hot or cold areas of the coil face (or otherwise broad tem- perature differences and stratification) are usually indications that one or more circuits are air-locked internally. This can result in coil freeze-up (a condition NOT covered by warranty).

Refrigerant coils may be rotated for opposite hand applica- tions, maintaining the proper airflow direction.

Do not reposition the distributor(s), they will perform equal- ly well in upflow or downflow positions. When soldering expansion valves to up-feed distributors, use the minimum satisfactory amount of solder to prevent damaging the valve or plugging passages.

DIRECT EXPANSION COILS — Rotate the coil in vertical plane and reinstall. Distributor must be on downstream side of coil. (Refer to Fig. 42).

CHILLED WATER AND HOT WATER COILS — These coils can be rotated. If coil is rotated in vertical plane and reinstalled with counterflow maintained, supply will be at the top of the coil and return will be at the bottom. Ensure coil is continuously vented and water velocity is maintained to prevent air binding.

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