Weil-McLain Evergreen EVG 70 Manual page 68

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Evergreen control operation
Outdoor reset operation
1. Set desired temperatures for space heating zones.
2. For an explanation of the target temperatures and associated
outdoor temperatures, see Figure 63 .
3. The temperature settings discussed below are accessed in the
priority menu for the applicable system. For detailed explanations
of the priority menus, see Figure 71, page 81 .
SUPPLY MAX
1. Set Supply max to the required supply water temperature for the
system at design maximum heat loss (typically 180°F for fi nned
tube baseboard on new installations).
SUPPLY MIN
1. Supply Min should equal the desired minimum supply water
temperature for the system.
2. This could be set as low as 70°F, which would supply "zero
heat" when outdoor temperature is 70°F, because supply water
temperature would equal room temperature.
3. See examples in Figure 63 .
OD RESET MAX
1. OD RESET MAX means the outdoor temperature at which the
target temperature reaches its minimum (Supply Min).
2. In the examples of Figure 63 , this occurs at 70 °F (the factory
default).
OD RESET MIN
1. OD RESET MIN means the outdoor temperature at which the
target temperature reaches its maximum value (Supply max).
2. In the examples of Figure 63 , this occurs at 0°F outside (the factory
default setting).
3. OD RESET MIN should equal the ODT (outdoor design
temperature) for the installation's location.
Remote target operation (0–10VDC input)
1. This function allows a remote analog input to regulate the supply
temperature for control operation/modulation. This can be done
for any priority, including network and local priorities for multiple
boiler networks.
2. The settings discussed below are accessed in the priority menu
for the applicable system. For detailed explanations of the priority
menus, see Figure 71, page 81 .
3. See Figure 64 for an explanation of target temperature vs voltage
when using remote target operation.
4. In the priority menu for the applicable system, select 0-10V for
the TARGET ADJUST setting.
5. In the same priority menu, select the VOLTS FOR MIN and VOLTS
FOR MAX values. VOLTS FOR MIN sets the voltage value for the
desired minimum supply temperature. VOLTS FOR MAX sets
the voltage value for the desired maximum supply temperature.
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Figure 63
Outdoor reset operation
Figure 64
Remote target operation
Remote modulation operation
(0–10VDC input)
1. To use 0-10VDC for remote modulation, go to
Contractor Menu -> Assign Inputs. Then change Input
1's source to 0-10V. The priority that is assigned to Input
1 cannot be used by any other Input.
2. The boiler comes on at 0.9VDC and turns off at 0.8VDC.
2 VDC = 20% input. 10VDC = 100% input. These
voltage settings are not adjustable.
Part number 550-100-191/0917