Balancing controller fails to shut off the HVAC unit
under some circumstances
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A/C is not shut off when all the zones are disabled
Zone status (whether enabled and/or voting) wasn't being
checked when calculating the total demand. Fixed.
Damn, I thought I fixed it. The A/C is not shut off when all
the zones are disabled.
A/C is not shut off if the remaining zones have a positive
demand, but it is on the rising and didn't reach the zone
controller trigger point yet.
When the setpoint is changed in such a way that the demand
is higher than the trigger point, and then the zone is
disabled, the A/C shuts off OK.
Clarification: the symptoms described earlier were pertinent
to balancing controller only. It seems that this controller
is very reluctant to lower the calculated demand value even
if all the zones are disabled. It may be a good idea to
expire the temperature readings in the
AbstractZoneController itself - right now it seems that the
last calculated demand value is just stuck there forever.
This bug seems to be related to bug #866442, as well as some
others. Indeed, it takes forever for demand to go down to
zero if it is already low, even if the zone temperatures are
lower than setpoints, but more than setpoint minus "happy"
offset. In this case, the demand drop is caused by P
components rising to offset the demand and eventually
reaching the threshold, which causes HVAC to stop.
Hope that this bug is gone for good now.
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