Installation and Operation Manual
TFTN 085-199
42
10.2 Near Boiler Plumbing
TFTN boilers are intended solely for use in pressurized closed-loop heating systems operating with a minimum pressure of
12 PSI at the boiler outlet. Carefully follow the instructions and piping diagrams illustrated in this section.
The TFTN boiler is NOT
approved for operation in an “open system”, thus it cannot be used for
direct potable water heating or process heating of any kind.
Pressure Relief Valve
–
A 30 PSI Pressure Relief Valve is factory supplied with each unit, and must be field installed in the
vertical position, with the outlet facing horizontally and piped towards the floor away from where it could be harmful;
see Figure 10-1 for recommended location.
Note:
TFTN085-199 models have a maximum allowable operating pressure of 50 PSI. The maximum allowable operating
pressure of TFTN285-399 models is 80 PSI
If installed in the incorrect orientation (e.g., horizontally with drain pipe out the bottom) the relief
valve may not function properly resulting in property damage or personal injury.
Ensure the discharge of the pressure relief is piped to a location where the steam or water will not
cause property damage or serious injury.
Pressure & Temperature Gauge
–
TFTN units come with a factory supplied Pressure and Temperature Gauge. The gauge
must be installed at the boiler outlet prior to any circulators.
Auto Air Vent
–
Install the factory supplied auto air vent directly above the outlet fitting on the top of the unit; see Figure
10-1. Open
the auto air vent’s vent
-cap to promote the removal of air during commissioning of the boiler and to avoid
malfunctioning of the LWCO. Once the air is removed from the system, close the vent-cap to prevent water from leaking
onto the boiler.
Low Water Cutoff (LWCO)
–
TFTN boilers are provided with a factory installed LWCO switch which incorporates a Test Button
and Power and Low Water indicator lights. Perform the following Operational Test Procedure before placing the boiler
in service, and ensure Maintenance is carried out with the following schedule.
Do not run the boiler unattended until the following procedure is completed. Failure to follow
this procedure may lead to unsafe boiler operation resulting in fire, property damage and loss of
life.
Operational Test Procedure (LWCO)
1.
Before introducing water to the boiler, turn the power on; both the green “POWER” LED and amber “LOW WATER” LED
should illuminate. Generate a burner demand; the burner should not fire and error
“
LWCO Open
” should appear on the
screen. Contact NTI for assistance if this does not happen.
2.
Fill the boiler with water; the “LOW WATER” LED should turn off.
Press the TEST/RESET button on the LWCO to reset
the circuit
–
burner should now fire.
3.
With the burner firing, press the TEST/RESET button to simulate a low
water condition; the amber “LOW WATER” LED
should illuminate, and the burner should turn off.
Maintenance (LWCO)
•
Every Year
–
perform Step 3 from the Operational Test Procedure above.
•
Every 5-years
–
Remove the LWCO and clean all surfaces in contact with water.
