I asked Honeywell whether or not they warranty a thermostat that was bought on-line.  A consumer had mentioned that they were unable to get a replacement under warranty when they bought from Amazon.com.  Here is Honeywell's reply (my bolding emphasis):

<quote>
Thank you for contacting Honeywell.

Honeywell does not sell products online and it is advisable to purchase the RTH7600D thermostat from a retail store like Lowes, Home Depot etc. The RTH7600D thermostat is covered under one year warranty which is honored from the place of purchase.

Honeywell Customer Care
<quote>