Thomas & Betts UDAS, UDAP dimensions Unit Heater Location cont’d, Hanging the Heater

10.Unit Heater Location (cont’d)

NOTE: Venting requirements may affect location. Consult the Venting Manual for this heater before making final determination.

Hazards of Chlorine - applies to location of Model UDAS heater with regard to combustion air inlet

For best results, the heater should be placed with certain rules in mind. In general, a unit should be located from 8 to 12 feet (2.4-3.7M) above the floor. Units should always be arranged to blow toward or along exposed wall surfaces, if possible. Where two or more units are installed in the same room, a general scheme of air circulation should be maintained for best results.

Suspended heaters are most effective when located as close to the working zone as possible, and this fact should be kept in mind when determining the mounting heights to be used. However, care should be exercised to avoid directing the dis- charged air directly on the room occupants.

Partitions, columns, counters, or other obstructions should be taken into consider- ation when locating the unit heater so that a minimum quantity of airflow will be deflected by such obstacles.

When units are located in the center of the space to be heated, the air should be discharged toward the exposed walls. In large areas, units should be located to discharge air along exposed walls with extra units provided to discharge air in toward the center of the area.

At those points where infiltration of cold air is excessive, such as at entrance doors and shipping doors, it is desirable to locate the unit so that it will discharge directly toward the source of cold air from a distance of 15 to 20 feet (4.6-6.1M).

CAUTION: Do not locate the heater where it may be exposed to water spray, rain, or dripping water.

The presence of chlorine vapors in the combustion air of gas-fired heating equip- ment presents a potential corrosion hazard. Chlorine found usually in the form of freon or degreaser vapors, when exposed to flame will precipitate from the com- pound, and go into solution with any condensation that is present in the heat ex- changer or associated parts. The result is hydrochloric acid which readily attacks all metals including 300 grade stainless steel. Care should be taken to separate these vapors from the combustion process. This may be done by wise location of the unit vent and combustion air terminals with regard to exhausters or prevailing wind directions. Chlorine is heavier than air. Keep these facts in mind when deter- mining installation location of the heater in relation to building exhaust systems.

11.Hanging the Heater

WARNINGS: Check the supporting structure to be used to verify that it has sufficient load carry- ing capacity to support the weight of the unit. Suspend the heater only from the threaded nut retainers or with a man- ufacturer provided kit. Do NOT suspend from the heater cabinet.

Before suspending the heater, check the supporting structure to be used to verify that it has sufficient load-carrying capacity to support the weight of the unit.

Model UDAP

Size	30	45	60	75	100	125	150	175, 200	225	250	300	350	400
lbs	54	59	67	72	96	101	172	187	203	215	269	294	306
kg	24	27	30	33	44	46	78	85	92	98	122	133	139
Model UDAS
Size	30	45	60	75	100	125	150	175, 200	225	250	300	350	400
lbs	55	60	68	73	97	102	173	188	204	216	270	295	307
kg	25	27	31	33	44	46	78	85	93	98	122	134	138

When the heater is lifted for suspension, support the bottom of the heater with plywood or other appropriately placed material. If the bottom is not supported, damage could occur. Before hanging, verify that all screws used for holding ship- ping brackets were re-installed in the cabinet.

The heater is equipped for either two-point or four-point suspension. A 3/8"-16 threaded nut retainer is located at each suspension point. See Dimensions in Para- graph 5 and the illustration in FIGURE 7A.

Form RZ-NA I-UDA, P/N 195673 Rev 5, Page 10