Schematic Tankless Heater Piping

Figure 36: Minimum Piping Requirements for V9A Tankless Heater Manifolds

Table IV: Tankless Heater Ratings

Boiler	Number of V9-2 Tankless Heaters Installed
Model	1	2	3	4
	1	2	3	4
V903A	6.75	---	---	---
V904A	7.5	---	---	--
V905A	7.5	---	---	---
V905A	7.5	---	---	---
V906A	7.5	15	---	---
V908A	7.5	15	---	---
V909A	7.5	15	22.5	---
V910A	7.5	15	22.5	---
V911A	7.5	15	22.5	---
V912A	7.5	15	22.5	30

Figure 37a: Schematic Tankless Heater Piping	Notes:

1. Ratings are given in gallons per minute continuous flow of water heated from 40°F to 140°F with 200°F boiler water.

2. For tankless heater quantities less than maximum allowable, it is important that water heaters be centrally located in the boiler.

See Figure 8 for appropriate locations.

3. Tankless heater pressure drop is 5.5 PSI at