ground loop systems will not experience overcooling of the
HWR COMPONENT FUNCTIONS — The proportional controller operates on 24 VAC power supply and automatically adjusts the water valve based on the
The loop pump circulates condenser water through the hy- dronic reheat coil during the reheat mode of operation (refer to Fig. 33). In this application, the loop pump is only energized during the reheat mode of operation. The hydronic coil is uti- lized during the reheat mode of operation to reheat the air to the set point of the proportional controller. Condenser water is di- verted by the motorized valve and pumped through the hydron- ic coil by the loop pump in proportion to the control set point. The amount of reheating is dependent on the set point and how far from the set point the supply air temperature is. The factory set point is 70 to 75 F, generally considered "neutral" air.
Deluxe D Control Accessory Relay Configura- tions — The following accessory relay settings are applica- ble for Deluxe D control:
CYCLE WITH FAN — In this configuration, the accessory relay 1 will be ON any time the Fan Enable relay is on. CYCLE WITH COMPRESSOR — In this configuration, the accessory relay 2 will be ON any time the Compressor relay is on.
DIGITAL NIGHT SET BACK (NSB) — In this configura- tion, the relay will be ON if the NSB input is connected to ground C.
NOTE: If there are no relays configured for digital NSB, then the NSB and override (OVR) inputs are automatically config- ured for mechanical operation.
MECHANICAL NIGHT SET BACK — When NSB input is connected to ground C, all thermostat inputs are ignored. A thermostat set back heating call will then be connected to the OVR input. If OVR input becomes active, then the Deluxe D control will enter night low limit (NLL) staged heating mode. The NLL staged heating mode will then provide heating dur- ing the NSB period.
WATER VALVE (SLOW OPENING) — If relay is configured for Water Valve (slow opening), the relay will start 60 seconds prior to starting compressor relay.
OUTSIDE AIR DAMPER (OAD) — If relay is configured for OAD, the relay will normally be ON any time the Fan Enable relay is energized. The relay will not start for 30 minutes fol- lowing a return to normal mode from NSB, when NSB is no longer connected to ground C. After 30 minutes, the relay will start if the Fan Enable is set to ON.
CAUTION
To avoid equipment damage, DO NOT leave system filled in a building without heat during the winter unless anti- freeze is added to system water. Condenser coils never fully drain by themselves and will freeze unless winterized with antifreeze.
Table 17 — HWR Operating Modes
MODE |
|
| INPUT |
|
|
|
| OUTPUT |
|
| |
O | G | Y1 | Y2* | H | O | G | Y1 | Y2* | Reheat | ||
| |||||||||||
No Demand | On/Off | Off | Off | Off | Off | On/Off | Off | Off | Off | Off | |
Fan Only | On/Off | On | Off | Off | Off | On/Off | On | Off | Off | Off | |
Cooling Stage 1 | On | On | On | Off | Off | On | On | On | Off | Off | |
Cooling Stage 2 | On | On | On | On | Off | On | On | On | On | Off | |
Cooling and Dehumidistat† | On | On | On | On/Off | On | On | On | On | On/Off | Off | |
Dehumidistat Only | On/Off | Off | Off | Off | On | On | On | On | On | On | |
Heating Stage 1 | Off | On | On | Off | Off | Off | On | On | Off | Off | |
Heating Stage 2 | Off | On | On | On | Off | Off | On | On | On | Off | |
Heating and Dehumidistat** | Off | On | On | On/Off | On | Off | On | On | On/Off | Off |
*Not applicable for single stage units; Full load operation for dual capacity units.
†Cooling input takes priority over dehumidify input.
**Deluxe D is programmed to ignore the H demand when the unit is in heating mode.
NOTE: On/Off is either on or off.
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