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vitodens 100 with zvc controls...

I have the Taco ZVC 404 exp with a 600 post purge card installed.  DHW on the boiler control is wired to XX on the card, RT on the boiler is wired to the end switch on the zone control...

The issue I have (if it's an issue at all) is the boiler seems to run for a few minutes after all thermostats stop calling for heat.  The zone control shuts down all the zone valves and shuts down the system pump, but the boiler keeps the room heat icon on the control panel and the boiler circulator spinning for several minutes.

Im using one end switch to power the system pump, and the other is for the boiler RT terminals.  That boiler endswitch gets energized even when the DHW is calling, so after the post purge card shuts down the DHW system, the boiler still has the room heat icon on the control panel for several minutes and the boiler pump runs.

Am I missing something here?


  • AlexS
    AlexS Member Posts: 69
    while we're discussing controls...

    Can someone recommend a good thermostat?  I guess I want to use a floor sensing model, are the honeywell 115 series alright?
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