Heat Controller HBH/V manual Performance Data Selection Notes, Example

Engineering Design Guide HBH/V SERIES Heat Controller, Inc.

For operation in the shaded area when water is used in lieu of an anti-freeze solution, the LWT (Leaving Water Temperature) must be calculated. Flow must be maintained to a level such that the LWT is maintained above 40°F [4.4*C] when the JW3 jumper is not clipped (see example below). This is due to the potential of the refrigerant temperature being as low as 32°F [0°C] with 40°F [4.4°C] LWT, which may lead to a nuisance cutout due to the activation of the Low Temperature Protection. JW3 should never be clipped for standard range equipment or systems without antifreeze.

Example:

At 50°F EWT (Entering Water Temperature) and 2.25 gpm/ton, a 3 ton unit has a HE of 27,300 Btuh. To calculate LWT, rearrange the formula for HE as follows:

HE = TD x GPM x 500, where HE = Heat of Extraction (Btuh); TD = temperature difference (EWT - LWT) and GPM = U.S. Gallons per Minute.

TD = HE / (GPM x 500)

TD = 27,300 / (6.75 x 500)

TD = 8°F

LWT = EWT - TD

LWT = 50 - 8 = 42°F

Performance Data

Selection Notes

AT 80/67°F					Heating - EAT 70°F
/Tot	kW	HR	EER	Airflow	HC	kW	HE	LAT	COP
tio				CFM
recommended				710	11.6	1.05	8.2	85.1	3.25
				825	11.7	1.02	8.4	83.2	3.38
3	0.58	24.1	38.3	710	13.6	1.09	10.1	87.8	3.66
5	0.59	24.4	38.3	825	13.8	1.06	10.3	85.5	3.81
3	0.57	24.3	39.2	710	14.2	1.09	10.7	88.5	3.81
5	0.58	24.7	39.2	825	14.4	1.06	10.9	86.1	3.97
2	0.56	24.4	39.8	710	14.4	1.09	10.9	88.8	3.86
5	0.57	24.7	39.8	825	14.6	1.06	11.1	86.3	4.02
6	0.65	25.1	35.3	710	16.1	1.15	12.3	90.9	4.08
8	0.66	25.5	35.3	825	16.2	1.12	12.6	88.2	4.25
5	0.61	25.2	37.9	710	16.7	1.15	13.0	91.8	4.25
8	0.62	25.5	37.9	825	16.9	1.12	13.3	89.0	4.42
5	0.6	25.2	38.3	710	16.9	1.16	13.2	92.1	4.30
8	0.61	25.6	38.3	825	17.1	1.12	13.5	89.2	4.47
8	0.74	25.2	30.7	710	18.3	1.18	14.5	93.9	4.56
0	0.75	25.6	30.7	825	18.5	1.14	14.8	90.8	4.75
7	0.69	25.3	33.4	710	19.1	1.18	15.2	94.8	4.73
0	0.70	25.6	33.4	825	19.3	1.15	15.5	91.6	4.93
7	0.67	25.3	34.1	710	19.3	1.18	15.4	95.1	4.78
0	0.68	25.6	34.1	825	19.5	1.15	15.7	91.9	4.98
0	0.85	24.8	25.9	710	20.4	1.21	16.5	96.6	4.93
3	0.86	25.1	25.9	825	20.6	1.18	16.8	93.2	5.13
9	0.78	25.1	28.6	710	21.2	1.22	17.3	97.7	5.10
2	0.80	25.4	28.6	825	21.5	1.18	17.6	94.1	5.31
9	0.77	25.1	29.4	710	21.5	1.22	17.5	98.0	5.15
1	0.78	25.5	29.4	825	21.7	1.19	17.8	94.3	5.36
2	0.97	24.0	21.4	710	22.4	1.23	18.4	99.2	5.35
4	0.98	24.3	21.4	825	22.7	1.19	18.8	95.4	5.57

In this example, as long as the EWT does not fall below 50°F, the system will operate as designed. For EWTs below 50°F, higher flow rates will be required (open loop systems, for example, require at least 2 gpm/ton when EWT is below 50°F).

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