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dgrab · Jan 27, 2009, 08:20 AM

Does anyone know of a honeywell touchscreen thermostat that has six-wire compatibility (R, W, Y, G, and O and B wires)? I know there's one from White Rodgers but was wondering if anyone knew of one from honeywell?

KISS · Jan 27, 2009, 09:23 AM

"B" could be Common(C) or the opposite state of "O".

The opposite state of"O" is easy to generate.

Rc and Rh are used in many new stats. If you connect Rh to Rc, you get the old terminal "R".

If R and C are used, there will be 24 VAC between these terminals at all times. Batteries are not required for operation. They may be used for backup.

Check out the Honeywell VisionPro series at Furnace Filters, Air Conditioner Filters, Air Quality - iaqsource. These will require extensive setup programming.

Can you provide a little mor einformation?

dgrab · Jan 27, 2009, 09:49 AM

Hi! Carrier conventional gas forced hot air with A/C. No heat pump.

The control panel is an EWC ultrazone ewc-st-2d with two zones. Zone two tstat three wires - piece of cake R W Y. Zone two heat/cool operation dictated by zone one setting.

Zone one tstat needs six wires as the control panel needs both o and b wires (cool active reversing and heat acting reversing valves) are required. Many tstats out there only have the one. See my other post (https://www.askmehelpdesk.com/heatin...ir-308822.html) if you wish.

Thanks for the help!

KISS · Jan 27, 2009, 10:08 AM

OK, piece of cake. Take O or B and run to a DPDT 24 vac coil relay. The other side of the coil goes to (C).

Connect the common terminals of both poles together and connect to R. One side, (NC or NO) would Be B and the other side (NO or NC) would be O.

You really want to use a DPDT relay here.

hvac1000 · Jan 27, 2009, 11:52 AM

According the EWC on page 6 of this

http://www.ewccontrols.com/acrobat/090375a0115.pdf

This Honeywell will work without a relay

http://customer.honeywell.com/techli...it/69-1849.pdf

There are other brands that will work also.

If in doupt contact EWC or Honeywell or both. Both numbers are on the literature I provided.

I hate relays on thermostat circuits especially if you have to take the current draw into consideration for anticipator settings/adjustments or type heat settings for the auto anticipator adjustments. Not saying it will not work. The EWC unit uses the B&O switch circuits on a separate basis that is why many thermostats will not work.

Some of this info was posted for you on your other posting about these problems with a warning about possible conflicts. To be sure I would call EWC and have a chat with support to make dang sure of your thermostat requiremants and selection.

dgrab · Jan 27, 2009, 01:41 PM

Spoke to EWC. There are only 4 thermostats (all isted in the doc) that will work with the control board I have. Nothing new will, which sucks. I wanted something better than the old kind... Thanks for all of the help! Really appreciate it!!

KISS · Jan 27, 2009, 02:32 PM

When you taked with them, did you mention the DPDT relay method?

You can take your current stat and try the method. I suspect it will work just fine.

The XT424524 and a socket to match from here:

relay

If you could find where to buy these guys, even this would work: http://www.functionaldevices.com/pdf/RIBM2401D.pdf

dgrab · Jan 27, 2009, 02:35 PM

I did not - he was pretty insistent that all current new tstats that have the same subbase functionality won't work with my control panel. Didn't make any sense to me but looks like I'll have to stick with my robertshaw 9610 :(

KISS · Jan 27, 2009, 02:39 PM

I doubt it very much.

Do you understand what I am proposing?

As I said, you can test with your current set up.

dgrab · Jan 28, 2009, 12:27 PM

Just wanted to close the loop on this thread; there are only 4 models of tstats that work with my control board, and they are in the EWC page mentioned above.

I did speak with John at EWC and he informed me that there is one new tstat (the White-Rodgers 1f95-1271) that works with my panel.

FYI for anyone out there in a similar scenario.

All the best, and thanks again for all of your help! Was very helpful, and much appreciated!

KISS · Jan 28, 2009, 02:19 PM

I hate to say it, but most Customer Service Reps are not engineers and they have rehearsed scripts.

There is an old saying that basically says "Trust, but verify."

"O" has a state opposite of that of "B". When "O" has 24 VAC on it with respect to (C), "B" has zero and vice versa.

Look here for a white-rogers stat on page #2:

http://www.white-rodgers.com/wrdhom/...pg0186_187.pdf

Under the operation of O/B. That functionality is SO EASY to obtain.

dgrab · Jan 28, 2009, 02:23 PM

Sure, but the EWC Chief Engineer was very helpful via email for me and he met my needs exactly. Being prompt, quick, and courteous makes talking to them a path I'd recommend to anyone else that has their components. I also don't have to do a double throw relay either, so in getting a new tstat it's a win-win for me and the house. Thanks!

hvac1000 · Jan 28, 2009, 03:01 PM

Many times it is easier to roll with the flow then try to swim up stream. I am not big on adding relays when there is a unit that will work without relays especially when a homeowner is involved. The relay idea will work since I have been forced to play that game before but if I have the option I will go with a stat that will get the job done without the extra relay. dgrab make sure to post back and let us know how it all worked out.

dgrab · Jan 28, 2009, 03:04 PM

I most certainly will post back in 3-5 days when I get the new device! Thanks hvac1000 for all of the expert help and assistance!

dgrab · Feb 16, 2009, 05:12 AM

The WR thermostat I got works perfectly! Problem solved!

hvac1000 · Feb 16, 2009, 05:40 AM

Glad it all worked out for you.