Capacity Tables for NT Series
STEAM
BTU/hour
| P.D.* with 10 PSI Inlet |
3.5 Cv 1-1/4″ Valves |
2.74 Cv 1″ Valves |
2.5 Cv 3.4″ Valves |
1.8 Cv 1/2″ Valves |
| 1 psi | 48,000 | 39,000 | 36,000 | 28,000 |
| 3 psi | 87,000 | 70,000 | 65,000 | 46,000 |
| 5 psi | 113,000 | 91,000 | 84,000 | 63,000 |
| 7 psi | 130,000 | 104,000 | 96,000 | 72,000 |
| 10 psi | 162,000 | 130,000 | 120,000 | 90,000 |
*P.D. = Pressure Drop
Capacity measured with 10 psi inlet preasure.
EDR = Equivalent Direct Radiation (in ft.2)
EDR = (BTU/hr) / 240
BTU/hr = 240 x EDR
BTU/hour – lbs. steam/hour x 1000
HOT WATER
BTU/hour**
| **Pressure Drop Ft. |
P.D. PSI |
3.5 Cv 1-1/4″ Valves |
2.74 Cv 1″ Valves |
2.5 Cv 3/4″ Valves |
1.8 Cv 1/2″ Valves |
| 1 | .43 | 21,000 | 17,000 | 16,500 | 12,000 |
| 2 | .87 | 28,000 | 23,000 | 22,000 | 15,500 |
| 4 | 1.7 | 44,000 | 35,000 | 32,500 | 23,500 |
| 6 | 2.6 | 53,000 | 43,000 | 40,000 | 29,000 |
| 8 | 3.5 | 64,000 | 51,000 | 47,000 | 33,500 |
| 10 | 4.3 | 70,000 | 56,000 | 52,000 | 37,500 |
| 12 | 5.2 | 77,000 | 62,000 | 57,000 | 41,000 |
| 14 | 6.1 | 83,000 | 67,000 | 62,000 | 44,500 |
| 16 | 7.0 | 88,000 | 71,000 | 66,000 | 47,500 |
EDR (Equivalent Direct Radiation in ft.2) for hot water
| Water Temperature | Cast Iron Radiator | Convector |
| 200°F | 209 | 205 |
| 190°F | 187 | 183 |
BTU/hour = EDR in ft.2 x (Appropriate number from above EDR Table)
For example 205 for 200°F water in convector.
**Assumes 20°F drop in water temperature through radiation.
GPM = CvvP.D.
BTU/hour = GPM x 10,000
1Ft. H2O = .433 psi
BULLETIN: NTCT-1705 – Capacity Tables for “NT” Series Valves