Is this contractor info on zoning correct?

[homebound]

Hello,

I've been trying to understand some of the mechanics of zoning. I've read a lot in this forum so I think know something about it now. But I have a couple of questions:

I asked my HVAC contractor about the variable speed and/or multi-speed blower option. I thought they would allow the system to run longer and be more efficient and dehumidfy more.

However, he says a single speed blower works fine and multi-/variable speeds are a waste of money. He says after the blower comes on in the variable unit, it will run slower at first but automically turn on to high speed after a few minutes if the desired zone temperature isn't reached pretty soon. It won't run at a slow speed for very long time even if just one small zone is on. It will go full blast after just a short time. So, "short cycling" still happens and is not really changed very much by using the more expensive equipment. And the super-dehumidifying claims are just advertising nonsense.

Is that so?

Also, I read about multi-position dampers being used in the supply duct and letting other zones be used as partial "dumps" to minimize inefficiencies and problems with bypass. He did not know anything about this and just used "full open" or "full closed" dampers. I had no answer to his question, "If you dump air into zones other than the one that wants the air, how do you stop the other zones from getting too hot or too cold?" I don't know. Any help?

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[t527ed]

find a contractor that understands zoning with a variable speed blower.

no partially open dampers or bypass needed with the right systems.

[iraqveteran]

Variable Speed is the way to go.

Better performance and more comfort.

Dump runs are not needed if the system is sized properly and the ductwork is designed properly.

Sounds like your contractor is under-educated or just plain doesn't want to mess with it.

I would look for another contractor. Get several bids and talk to as many as you can. Take your time, and make the right decision. And ask questions. We're here to help when we can.

[beenthere]

There are several different technologies out for zoning.

VS claims of dehumidification are not just ad BS.
But is does have to be done right in order to work, and your contractor is not the right contractor for it.
The systems that dump some air into zones not calling monitor how much air that zone is getting and then closes if it starts to over shoot.
Again. your contractor is not the one to use for this type system.
Matered systems do it almost the same.

Get other estimates.
If you already signed with this contractor. Too late to change now.