Re: Electronically controlled HVAC damper?

["C Bower" <cbower@xxxxxxxxxxxxx>]

While automating your HAVC system two other suggestions:

1) install a flow switch to shut down the heat or a/c if there is low flow.
Problems such as broken fan belts can result in a burned out a/c compressor
if your not home and it keeps running with no air flow trying to answer a
cooling call.  This would also address the problem of too many regisers
being closed.  You'd need to find a flow switch from an HVAC distributor.

2) a smoke detector in the return air duct (commonly used industrially and
in commercial buidings, but not in residences) could save your life by
shutting down the system if smoke is detected, otherwise a modern forced air
system can efficiently fill the whole house with smoke or CO from a fire in
one room.  Also, connect your central fire alarm (if you have one) to shut
off the system in the event of fire for the same reason.   Smoke detectors
for use in air ducts are available commercially.  In our highrise building,
the system switches to full fresh air at max fan if the fire alarm goes off,
but shuts down if smoke is detected in the ducts.

Just a thought

"Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote in message
news:dsudnT84DvihVWXeRVn-gQ@xxxxxxxxxx
>> Is it enough to make sure that at least one zone is open? or is it more
> complicated?
>
> It depends on the setup.  If you short-cycle a furnace, you run the risk
> of
> cracking the heat exchanger and allowing CO into the house.  It all
> depends
> on the unit's safety features and configurability.  You need to know, at a
> minimum, how much the air heats up from furnace air inlet to outlet.  If
> it
> leaves the furnace at say X degrees unmodified but X+30 degrees after your
> zoning, you need to do something because you've lowered the over-all
> airflow
> through the system too much.
>
> If you are going to DIY zone, factor in the cost of several good CO
> detectors and place them strategically throughout the house.
>
> --
> Bobby G.
>
>
>