Carrier PCV015-060 specifications Unit Start-UpCooling Mode, Operating Limits - 50PCH,PCV Units

Table 14 — Operating Limits — 50PCH,PCV Units

AIR LIMITS	50PCH,PCV
	Cooling (F)	Heating (F)
Min. Ambient Air – db	45	39
Rated Ambient Air – db	80.6	68
Max. Ambient Air – db	110	85
Min. Entering Air – db/wb	50	40
Rated Entering Air – db/wb	80.6/66.2	68
Max. Entering Air – db/wb	110/83	80
WATER LIMITS
Min. Entering Water	30	20
Normal Entering Water	50-110	30-70
Max. Entering Water	120	90
Normal Water Flow	2.5-3.0 gpm per ton
LEGEND

db — Dry Bulb wb — Wet Bulb

Scroll Compressor Rotation — It is important to be certain compressor is rotating in the proper direction. To determine whether or not compressor is rotating in the prop- er direction:

1.Connect service gages to suction and discharge pressure fittings.

2.Energize the compressor.

3.The suction pressure should drop and the discharge pressure should rise, as is normal on any start-up.

If the suction pressure does not drop and the discharge pressure does not rise to normal levels:

1.Turn off power to the unit. Install disconnect tag.

2.Reverse any two of the unit power leads.

3.Reapply power to the unit and verify pressures are correct.

The suction and discharge pressure levels should now move to their normal start-up levels.

When the compressor is rotating in the wrong direction, the unit makes more noise and does not provide cooling.

After a few minutes of reverse operation, the scroll com- pressor internal overload protection will open, thus activating the unit lockout. This requires a manual reset. To reset, turn the thermostat on and then off.

NOTE: There is a 5-minute time delay before the compressor will start.

Unit Start-Up Cooling Mode

1.Adjust the unit thermostat to the warmest position. Slowly reduce the thermostat position until the compres- sor activates.

2.Check for cool air delivery at unit grille a few minutes after the unit has begun to operate.

3.Verify that the compressor is on and that the water flow rate is correct by measuring pressure drop through the heat exchanger using P/T plugs. See Table 15. Check the elevation and cleanliness of the condensate lines; any dripping could be a sign of a blocked line. Be sure the condensate trap includes a water seal.

4.Check the temperature of both supply and discharge wa- ter. Compare to Tables 16-22. If temperature is within range, proceed. If temperature is outside the range, check the cooling refrigerant pressures in Tables 16-22.

5.Check air temperature drop across the coil when com- pressor is operating. Air temperature drop should be between 15 and 25 F.

Table 15 — Water Temperature Change

Through Heat Exchanger

	COOLING		HEATING
WATER FLOW RATE (GPM)	RISE (F)		DROP (F)
	Min	Max	Min	Max
For Closed Loop: Ground Source or	9	12	4	8
Cooling/Boiler Systems at 3 gpm/ton
For Open Loop: Ground Water Systems at	20	26	10	17
1.5 gpm/ton

Table 16 — 50PC015,018 Typical Unit Operating Pressures and Temperatures

ENTERING					COOLING							HEATING
	WATER	WATER	Suction	Discharge	Super-	Sub-	Water	Air Temp	Suction		Discharge	Super-	Sub-		Water		Air Temp
		FLOW
	TEMP		Pressure	Pressure	heat	cooling	Temp	Drop	Pressure		Pressure	heat	cooling		Temp		Rise
	(F)	(GPM/ton)					Rise								Drop
			(psig)	(psig)	(F)	(F)	(F)	(F) DB	(psig)		(psig)	(F)	(F)		(F)		(F) DB
		1.5	120-130	155-175	27-32	11-16	16.9-19.9	16-22	73-	83	268-288	8-13	4-	9	6.1-	8.1	15-21
	30	2.25	120-130	142-162	27-32	9-14	12.5-14.5	17-23	75-	85	270-290	8-13	4-	9	4.4-	6.4	16-22
		3	120-130	128-148	27-32	9-14	8.1-10.1	17-23	78-	88	272-292	8-13	4-	9	2.9-	4.9	16-22
		1.5	137-147	220-240	16-21	10-15	17.0-19.0	16-22	102-112		295-315	8-13	8-13		9.1-11.1		20-26
	50	2.25	137-147	206-226	16-21	8-13	12.6-14.6	17-23	106-116		297-317	8-13	8-13		6.9-	8.9	21-27
		3	137-147	192-212	16-21	8-13	8.4-10.4	17-23	110-120		299-319	8-13	8-13		4.7-	6.7	21-27
		1.5	142-152	287-307	7-12	10-15	15.9-17.9	16-22	131-141		324-344	9-14	10-15		12.1-14.1		25-33
	70	2.25	142-152	273-239	7-12	8-13	11.8-13.8	17-23	137-147		326-346	9-14	10-15		9.3-11.3		26-34
		3	142-152	259-279	7-12	8-13	7.8- 9.8	17-23	144-154		328-348	9-14	10-15		6.6-	8.6	26-34
		1.5	146-156	375-395	6-11	10-15	14.9-16.9	16-22	174-184		360-380	10-15	12-17		15.8-17.8		32-40
	90	2.25	146-156	361-381	6-11	8-13	11.0-13.0	17-23	180-190		367-387	11-16	12-17		11.9-13.9		33-41
		3	146-156	347-367	6-11	8-13	7.2- 9.2	17-23	187-197		374-394	12-17	12-17		8.0-10.0		33-41
	110	1.5	154-164	478-498	6-11	10-15	14.0-16.0	16-22	—		—	—	—		—		—
		2.25	154-164	461-481	6-11	8-13	10.2-12.2	16-22	—		—	—	—		—		—
		3	154-164	445-465	6-11	8-13	6.5- 8.5	16-22	—		—	—	—		—		—
		LEGEND
DB	— Dry Bulb
—	— No Heating Operation in This Temperature Range

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