Rheem Gas Hot Water Supply Heaters Recovery Capacities, General Flow and Piping Specifications

RECOVERY CAPACITIES

MODEL NUMBER		STYLE		INPUT BTU/Hr.		TEMPERATURE RISE – DEGREES F – GALLONS PER HOUR
wo/Pump	w/Pump	Indoor	Outdoor	NATURAL	40°	50°	60°	70°	80°	90°	100°	110°	120°	130°	140°
GBB136	GBBP136	*	*	136,000	330	264	220	188	165	147	132	120	110	101	94
GBC186	GBCP186	*	*	181,000	440	352	293	251	220	195	176	160	147	135	126
GBC264	GBCP264	*	*	264,000	640	512	427	366	320	284	256	233	213	197	183
GBC331	GBCP331	*	*	334,000	811	649	541	463	406	360	324	295	270	250	232
GBC399	GBCP399	*	*	399,000	967	774	645	553	484	430	387	352	322	298	276
GBC512	GBCP512	*	*	511,500	1240	992	827	709	620	551	496	451	413	382	354
GBC627	GBCP627	*	*	627,000	1520	1216	1013	869	760	676	608	553	507	468	434
GBC726	GBCP726	*	*	726,000	1760	1408	1173	1006	880	782	704	640	587	542	503
GBC825	GBCP825	*	*	825,000	2000	1600	1333	1143	1000	889	800	727	667	615	571
GBC926	GBCP926		*	926,000	2245	1796	1497	1283	1122	998	898	816	748	691	641
GBC962	GBCP962	*		961,700	2331	1865	1554	1332	1166	1036	933	848	777	717	665
GBC1083	GBCP1083		*	1,083,000	2625	2100	1750	1500	1313	1167	1050	955	875	808	750
GBC1125	GBCP1125	*		1,124,700	2727	2181	1818	1558	1363	1212	1091	991	909	839	779
GBC1178	GBCP1178		*	1,178,000	2856	2285	1904	1632	1428	1269	1142	1038	952	879	816
GBC1223	GBCP1223	*		1,222,500	2964	2371	1976	1694	1482	1317	1185	1078	988	912	847
GBC1287	GBCP1287		*	1,287,000	3120	2496	2080	1783	1560	1387	1248	1135	1040	960	891
GBC1337	GBCP1337	*		1,336,600	3240	2592	2160	1852	1620	1440	1296	1178	1080	997	926
GBC1413	GBCP1413		*	1,413,000	3425	2740	2284	1957	1713	1522	1370	1246	1142	1054	979
GBC1467	GBCP1467	*		1,467,000	3556	2845	2371	2032	1778	1581	1423	1293	1185	1094	1016
GBC1570	GBCP1570		*	1,570,000	3806	3045	2537	2175	1903	1692	1522	1384	1269	1171	1087
GBC1630	GBCP1630	*		1,630,000	3952	3161	2634	2258	1976	1756	1581	1437	1317	1216	1129
GBC1758	GBCP1758		*	1,758,000	4262	3409	2841	2435	2131	1894	1705	1550	1421	1311	1218
GBC1826	GBCP1826	*		1,825,600	4426	3541	2950	2529	2213	1967	1770	1609	1475	1362	1264

GENERAL FLOW AND PIPING SPECIFICATIONS

								Water Hardness
MODELS				SOFT					MEDIUM						HARD
			0-4 Grains Per Gallon					5-15 Grains Per Gallon					16 & Over Grains Per Gallon
Indoor	Outdoor	T	GPM	P	MPS	SHL	T	GPM		P	MPS	SHL	T	GPM	P	MPS	SHL
136	136	22	10	3.4	1-1/4	5.09	17	13		5.5	1-1/4	8.2	10	22	14.7	1-1/4	22
186	186	15	20	1.82	1-1/2	4.48	11	26		3	1-1/2	7.5	7	40	6.8	1-1/2	17
264	264	21	20	1.85	1-1/2	4.51	16	26		3.1	1-1/2	7.6	10	42	8.3	1-1/2	18.8
331	331	27	20	1.9	1-1/2	4.56	20	26		3.2	1-1/2	7.7	13	42	8.5	1-1/2	19
399	399	30	22	2.1	1-1/2	5.08	25	26		3.3	1-1/2	7.8	15	43	9	1-1/2	19.5
512	512	20	42	1.8	2	4.4	16	52		2.9	2	7	10	84	6.8	2	16.6
627	627	25	41	1.9	2	4.5	19	54		3.1	2	7.2	11	90	8.5	2	20.4
726	726	29	41	2	2	4.6	20	60		4	2	9.3	13	90	9	2	20.8
825	825	30	45	2.5	2	5.7	20	68		5.2	2	11.7	15	90	9.3	2	21.1
962	926	30	53	3.5	2-1/2	4.9	20	79		7.5	2-1/2	10.5	17	90	10.1	2-1/2	14.3
1125	1083	30	61	5.5	2-1/2	7.5	20	90		11.8	2-1/2	16	20	90	11.8	2-1/2	16
1223	1178	30	67	6.5	2-1/2	8.8	22	90		12	2-1/2	16.2	22	90	12	2-1/2	16.2
1337	1287	30	73	8.4	2-1/2	11	24	90		13.3	2-1/2	17.5	24	90	13.3	2-1/2	17.5
1467	1413	30	80	10.8	2-1/2	14.1	26	90		13.8	2-1/2	18	26	90	13.8	2-1/2	18
1630	1570	30	89	13.7	2-1/2	17.6	29	90		14.8	2-1/2	19	29	90	14.8	2-1/2	19
1826	1758	32	90	15.5	2-1/2	19.7	32	90		15.5	2-1/2	19.7	32	90	15.5	2-1/2	19.7

NOTE: Additional pipe fittings will increase the system head loss. Select a pump based on the water hardness, flow and system head loss. If water heater is more than two stories above the tank, consult the pump manufacturer.

T	– Temperature Rise, Degree F @ GPM Flow
GPM	– Gallons per Minute Flow
P	– Pressure Drop, Ft. thru Heat Exchanger
MPS	–	Minimum Pipe Size, NPT
SHL	–	System Head Loss

Sizing based on water heater and tank being placed 5 feet apart. The equivalent length of pipe valves and fittings in the system is as follows.

1-1/4" NPT = 65 Ft (136)

1-1/2" NPT = 70 Ft (186-399)

2" NPT = 75 Ft (512-825)

2-1/2" NPT = 80 Ft (926-1826)