Camus Hydronics DFH1100, Инструкция по установке, эксплуатации и обслуживанию

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Figure 24: Mode 1 Piping & Electrical Layout
Mode 2: Constant Temperature Control at System
Sensor
This mode is designed for constant temperature heating.
Once a heat demand is present, the BTC 1 modulates the
boiler burner to maintain the boiler target at the system
sensor. A heat demand is generated when 24VAC is
applied across CD (common demand) and Ht D (heat
demand). Dem 1 on the LCD display is lit.
If the system sensor is ½ (half) of the differential below the
BOIL TARGET, the BTC 1 then changes the proportional
modulation output to the START modulation setting, the
Stage contact (pins 15 & 16) closes to proceed to trial for
ignition. The burner remains at minimum modulation until
the flame is proved and then the modulating output
changes the boiler burner output to maintain the
programmed boiler target temperature at the system
sensor. If the system sensor reaches ½ (half) of the
differential above BOIL TARGET setting, the burner shuts
off. Once the external heat demand is removed, the BTC 1
turns off the appliance and operates the boiler pump based
on the PUMP DELAY setting. In this case, it is imperative
that the system pump operates continuously in order to
provide constant circulation past the system sensor.
The water temperature is controlled based on a fixed
setpoint (BOIL TARGET).The setpoint for inlet water is pre-
set to 120
o
F and the auto re-set limit is set to 210°F and is
fixed. In addition to the auto reset limit the factory installs a
manual re-set limit set to 250°F.
Figure 25: Mode 2 Piping & Electrical Layout
Mode 3: Dedicated Domestic Hot Water Operation
This mode is designed for domestic hot water. A DHW
sensor must be inserted into a temperature immersion well
within the DHW tank to function properly. The BTC 1
modulates the boiler based on the boiler inlet sensor to
maintain a tank temperature at the DHW sensor.
An internal heat demand is generated when the DHW
sensor drops ½ (half) of the tank differential setting below
the desired DHW tank temperature. Dem 1 is lit on the LCD
screen.
The BTC 1 then changes the modulation output to the
START modulation setting and closes the Stage contact
(pins 15 & 16) to proceed to trial for ignition. The burner
remains at minimum modulation until the flame is proved
and then modulating output changes the boiler output to
maintain the programmed boiler target temperature at the
boiler inlet sensor. Once the DHW tank reaches ½ of the
tank differential above the TANK TARGET setting, the
internal demand is removed and the boiler burner is shut
off. The pump circulates until the PUMP DELAY timer
expires.
The TANK TARGET setting is used to set the desired DHW
tank setpoint. The set-point for inlet water is pre-set to
130°F and can be adjusted, the auto re-set limit is set to
210°F and is fixed. In addition to the auto reset l imit the
factory installs a manual re-set limit set to 210°F .
Figure 26: Mode 3 Piping & Electrical Layout
Mode 4: Outdoor Reset using Boiler Inlet Sensor
This mode is designed for hydronic heating. Once a heat
demand is present, the BTC 1 turns on the appliance pump
and modulates the boiler to maintain the calculated outdoor
reset target at the boiler inlet sensor. Outdoor reset
calculates the boiler target temperature based on the
outdoor air temperature and reset ratio.
A heat demand is generated when a voltage between
24VAC and 120VAC is applied across CD (common
demand) and Ht D (heat demand). Once voltage is applied,
the BTC 1 turns on the Dem 1 segment in the display. If
warm weather shut down (WWSD) is activated, the WWSD
segment is lit.