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Updated December 15, 2008 0600am EST

I’m trying to find out what I’d need to control my HVAC (hot water in floor) from my computer at the office. I have WiFi at my home but no computer there. Is this possible?

First you need a gateway device that can connect your Ethernet (WiFi) network to a Z-Wave network. These devices (gateways) do not require a computer to operate. Some of the easiest to use are from Hawking, miCasaVerde, and HomeManageables. Then you will need a Z-Wave thermostat device. You say that you have a hot water system, some of these require special thermostats and some can use standard zone type thermostats; you will have to determine what kind you need. Z-Wave thermostats are available from Wayne-Dalton, Intermatic, RCS, and HAI, most of these should be able to control your system. I suggest you first contact the Z-Wave thermostat suppliers you can link to their websites and support through the Z-Wave Alliance and determine what will work with your system. Once you find the thermostat you need, then check out the gateways again using at the alliance web site and go to the members section as your starting point.

I’m looking to automate the fluorescent lighting and HVAC in a small office building. Can I use the available Z-Wave products in this application?

Yes you can, just make sure you use switches and no dimmers for the lighting. Also, try Intermatic or Elk products for large contactors if the lighting loads exceed 20 Amps or are 277 volt.

If each apartment in a building has its own Z-Wave network, how do I assure that one user does not interfere with another?

Each Z-Wave network starts with its own primary controller, this is the controller you use to start the network and to assign each new device in that network its node number or node ID. The process of giving this node ID to a new node is called inclusion, that is, the primary controller is including the new node into its network.

Every primary controller comes from the factory with its own unique home ID. When the primary controller includes a new node it shares its unique home ID and provides a unique node ID to the new node, so no two nodes have the same node ID and all nodes in a given network share the same Home ID. In your case each Z-Wave network in your building will be started with its own primary controller and thus will have its own unique home ID. The home ID prevents the networks from interfering with each other.

The home ID number is a 32-digit number. Licensed manufacturers are assigned blocks of numbers to use by Zensys Corporation so there is virtually no chance that duplicate home ID’s will occur. This system is much more robust than that of older home automation systems that provided only 16 home IDs.

When will Z-Wave products be available in New Zealand and Australia? And, is it possible to convert U.S. or European products to work on the New Zealand or Australian frequencies?

No, the manufacturer sets the specific operating frequency at the factory. Many manufacturers have requested information on providing AU compliant products so I think it is safe to assume that some products will be making it to market soon. If you have a favorite US or EU product or manufacturer I suggest you contact them and ask for AU specific products. When the manufacturers hear from consumers that there is demand then they usually react positively.

 

Mark Walters, our resident Z-Wave expert, is a home automation consultant and the former vice president of the Z-Wave Alliance. Mark is well versed in numerous home automation technologies including CE Bus, Insteon, X10, Z-Wave, ZigBee, and KNX.