Wow- what an awesome resource this site is... I am glad I found it.

Ok... I have an old HoneyWell 5 wire, line voltage, 120v thermostat (T651E 1000 8049), which runs the HVAC air/heat system in my condo.

It is broken, and I would like to replace it with a digital thermostat, but I can't find any 5 wire 120v digital thermostats at all. Any ideas? I checked Honeywell, and did a Google search, but I'm coming up blank.

Part II- If a replacement tstat doesn't exist, do I have to use all 5 wires? The settings I have now are Cool- High fan/Low Fan, Heat- High Fan/Low fan, and Off. Could I sacrifice--say the 'low cool'-- and use a 4 wire tstat, or is that just insane?

Thanks!

Here is a link to the wiring for your thermostat you have now.

http://customer.honeywell.com/techlit/pdf/60-0000s/60-0600.pdf


You will be better served if you replace your current stat with on for line voltage as you said. Most all digital thermostats are of the low voltage type.


White rodgers heat and cool line voltage. Note you will also need to buy a subbase to make it heat and cool.

http://www.white-rodgers.com/wrdhom/pdfs/06_Cat_pages/Cat_06_pg0032.pdf

All of these items will probably have to be ordered by a HVAC company or a company that will deal with you direct. Honeywell and White Rodgers are manufactures and sell only to there wholesalers.