NTI Trinity Lx 150, Инструкция по установке и эксплуатации

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Trinity Lx
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Installation and Operation Instructions Lx Series
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Low Water Cutoff (LWCO) / Safety Flow Switch – Trinity Lx150-400 boilers are provided with a factory
installed Water Pressure Switch; in the event the pressure drops below 10 psi, the burner is inhibited from
firing. Where required by the Authority having jurisdiction, an external LWCO, or Safety Flow Switch, may
have to be installed; see Figures 10-1(a) and (b) for Safety Flow Switch installation.
When using a Safety Flow Switch, it must be installed on the boiler outlet fitting (see
Figure 10-1) in accordance with the instructions provided with the flow switch. Install
the flow switch in a 1” diameter line for models Lx150-200, and a 1-1/4” diameter line
for models Lx300-400.
Models Lx500-800 come equipped with a factory installed flow switch installed in a 2”
diameter line. The flow switch is pre-plumbed with a Nema 4 rated enclosure and
prewired via liquid-tight conduit. According to ASME CSD-1, a flow switch must be
used in lieu of a Low Water Cut Off (LWCO) for a water tube boiler.
When external safety devices are used, such as a LWCO, Flow Switch, or a Temperature
Limiting Switch, they must be wired as per the instructions provided in this manual.
Refer to Section 12.0 for wiring instructions.
Boiler System Plumbing
The Trinity Lx boiler uses a low mass heat exchanger that requires a minimum rate of forced water circulation
any time the burner is operating (See Table 10-4 for minimum flow rates). To ensure the minimum flow rate is
attained, the boiler must be installed in a “Primary/Secondary” plumbing configuration utilizing “Closely Spaced
Tees” to de-couple the Boiler-Primary loop from the System-Secondary loop(s) (see Figures 10-2 and 10-3 for
examples). As well as a Primary/Secondary Loop Configuration utilizing closely spaced tees, a properly installed
system will as a minimum include the major components in Table 10-3.
Table 10-3 System Major Component Checklist
Factory Supplied Components Field Supplied Components

Pressure Relief Valve
1 
Boiler Loop Circulator (Pump B in Figure 10-2 or Pump C in Figure 10-3)

Pressure Gauge

DHW Loop Circulator (Pump A in Figure 10-2 and Figure 10-3, for
applications utilizing Indirect Fired Water Heater only)

Flow Switch (Lx500-800 only)

Central Heat (CH) Loop Circulator(s)
(CH Circulator - Pump C in Figure 10-2; Zone Circulators in Figure 10-3)

Central Air Removal Devices (i.e. Micro Bubbler or Air-Scoop)

Pressure Regulating “Fill Valve”

Backflow Preventor

Expansion Tank
Notes:
1
Refer to Table 10-2 for a list minimum Pressure Relief Valve specifications.
Circulating Pumps – Trinity Lx150-400 boilers are equipped with three 120VAC pump outputs, while the
Lx500-800 is equipped with 3 pump contacts (relays):
1. PUMP A
“DHW Pump” - operates during a Domestic Hot Water demand
2. PUMP B
“Boiler Pump” - operates during any demand
3. PUMP C
“CH Pump”
- operates during a Central Heat demand (CH1 or CH2)
Ensure pumps are oriented as per the manufacturers’ instructions. Wiring of these circulators will depend on the
system configuration chosen; see Figures 10-2 and 10-3. For further wiring details see Section 12.0.
Circulators responsible for forcing the water flow rate through the boiler must be sized
according to Table 10-4, see Figures 10-2 and 10-3 for details.
Failure to ensure the minimum water flow rate through the boiler when the burner is on
will not only reduce the operating efficiency of the boiler, but may also cause premature
failure, overheating and void the warranty. Failure to follow instructions may result in
fire, property damage, serious injury or death.