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Backup Heater Operation:
E2 AC (V18b) heater start condition:
1. Before the V18b can start, the ambient temperature (as
measured by C02 in Status, details menu), must be below the P57
setting.
2. When the compressor cannot meet the BTU load for a period of
15 minutes, based on the AC inlet water temperature < target
temperature by 3C, E2 (V18b) will turn on.
If the above 2 conditions are satisfied, V18b will start.
Only when E2 is on, the SSR control will start. E2 on/off control is as
explained below.
1. E2 will start during defrost and stop if AC inlet water
temperature is > or = to Target inlet water tempe3c.
2. When the compressor is on and E2 starts, the CX34 will re-target
the AC inlet water temperature set point by +3C.
If E2 stops, the EWT target will revert back to the original target
temperature.
3. If a P5 error is flagged, (water flow error ), E2 will stop.
Summary of Contents for V18-B
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