Camus Hydronics Valiant FT VA0080, Manual

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2.4.4 High Limit
A high limit probe is located on the outlet piping inside the
appliance cabinet. The setting of this control limits
maximum discharge water temperature. A manual reset
high limit will have a red reset button appear on the
touchscreen which must be pushed whenever water
temperature has exceeded the set point of the manual reset
limit. High Limit with manual reset is a standard feature on
all Valiant units.
WARNING REGARDING CHILLED WATER AND
HEATING COIL SYSTEMS
When an appliance is connected to a refrigeration system
where the same water is used for heating and cooling, the
chiller must be piped in parallel with the appliance.
Appropriate isolation valves; manual or motorized must be
provided to prevent the chilled water from entering the
appliance.
The appliance piping system of a hot water boiler
connected to heating coils located in air handling units
where they may be exposed to refrigerated air circulation
must be equipped with flow control valves or other
automatic means to prevent gravity circulation of the boiler
water during the cooling cycle.
Figure 19: Chilled Water System
2.4.5 Minimum Pipe Size Requirements
The equivalent number of straight feet of pipe for each valve
and fitting in the connecting piping must be considered to
properly arrive at the total equivalent feet of straight pipe in
the field installed piping to the appliance. For water
connection sizing; see the table below:
Model Water Connection
80 1”
110 1”
155 1”
199 1-1/4”
250 1-1/4”
299 1-1/2”
399 1-1/2”
Table 8: Valiant FT Pipe Sizes
HEAT EXCHANGER
The heat exchanger is of fully welded construction, and is
cylindrical in appearance. The heat exchanger is a vertical,
single-pass, counter-flow, fire-tube design. Models 80 MBH
to 155 MBH are designed to withstand 30 PSIG operating
pressure, while 199 MBH to 399 MBH are designed for
80PSI of operating pressure.
∆ T HEAT EXCHANGER ALGORITHM
The Valiant FT is constantly monitoring the inlet and outlet
water temperatures. The flow rates in the heat exchanger
must be maintained in accordance with Table 9. A safety
algorithm is also built into the control, so that as the ∆T
approaches 60°F the burner will modulate down to prevent
tripping of the high limit and to protect the heat exchanger.
LOW WATER TEMPERATURE SYSTEMS
In applications where the heating system requires supply
water temperatures below 110°F, connections may be
made directly to the Valiant FT. At incoming temperatures
of 120°F or lower this appliance achieves maximum
efficiency. Inlet temperatures must not drop below 40°F to
prevent freezing.
2.4.6 FLOW AND PRESSURE DROP AT A GIVEN ∆T
Input
KBtu/hr
Flow and Pressure Drop at given
∆ T
20°F 30°F 40°F
GPM
∆ P
GPM
∆ P
GPM
∆ P
80 7.6 1.7 5.1 0.1 3.8 0.6
110 10.4 2.6 7.0 1.5 5.2 0.9
155 14.7 5.0 9.8 2.5 7.4 1.7
199 18.9 2.7 12.6 1.5 9.4 1.0
250
23.7 4.3 15.8 2.3 11.9 1.6
299 28.4 3.2 18.9 1.6 14.2 1.1
399 37.9 5.0 25.3 2.5 18.9 1.6
Table 9: Valiant FT Flow and Pressure Drop (ft-hd) vs ∆ T
Model
80 110 155 199 250 299 399
Min Flow
3.0 4.2 5.9 7.6 9.5 11.4 15.5
Max Flow
17.0 17.0 17.0 27.0 27.0 27.0 38.0
Table 10: Valiant FT Minimum and Maximum Flow (USGPM)