NTI INSTALLATION MANUALS

Part 4 - Water Piping

TRX110C - TRX150C

E. Internal Circulation Pump

By-pass valve location

To calculate the size of the heating installation refer to the graph below.

Graph Representing the Available Circulation Pump Head

feet

24

20

16

12

8

Figure 16 - By-Pass Valve Location

4

0

0

1

2

3

4

5

6

7

gal/min

Table 11 - Internal Circulation Head Curve

Figure 17 - By-Pass Valve Assembly

G. CH and DHW Pressure Relief Valves

This boiler has a high-temperature shut-o switch built in as a standard safety feature. Therefore, a “pressure only” relief valve is required. DO NOT operate this appliance before the supplied pressure relief valve is installed with su cient relieving capacity in accordance with the ASME rating plate on the appliance. The pressure relief valve must be installed with the provided adaptor pipe in the top of the boiler as detailed in Figure 20. No other valves should be placed between the pressure relief valve and the appliance. Failure to comply with these guidelines can result in substantial property damage, personal injury, or death. WARNING

Figure 15 - Internal Circulation Pump NOTE: Ensure the Air Vent on the Internal Circulation Pump Remains Open after Installation

F. By-Pass Valve

This boiler has a by-pass valve which requires no adjustment. The by-pass valve protects the heat exchanger from overheating by guaranteeing a minimum ow rate of 2 gpm within the primary heat exchanger. This protects the primary heat exchanger from overheating when water circulation is insu cient or heating system load is reduced (ex: due to the response of thermostatic valves or zone valves). The by-pass valve is located: - in the left hydraulic block for TRX085 and TRX120 . - in the right hydraulic block , behind the three-way valve, for TRX110C and TRX150C .

TRX085 - TRX120

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