[SLDuus]

HEy. I have a two story house with a heat pump ( I think). There is a thermosat upstairs and one downstairs. I was told there is a damper in between to control air flow. I just changed the original thermostats to two new programmable Honeywells. The upstairs thermostat now controls the downstairs damper, and the down controls the upstairs. It is getting COLD in the house too. There was a Rc, W, O, Y, G and C wires. I hooked the W and O together since I have a heat pump. Can anyone help??

[hvac1000]

Need brand and EXACT model number of old upstairs thermostat.
Need the same info for the old downsatirs thermostat.

Need the model numbers for the new honeywell thermostats.

Since you have a zone type system I will also need the brand and Exact model of the zone control.

[SLDuus]

Thank. The original thermostat is a Honeywell TH311D1008. The new Honeywell is RTH6300B. I am not sure where to find the zone controller. Where would would that be? By the way, I removed the downstairs programmable, and put th eoriginal back on, and it seems to be working now... I would like to have both programmable though.. Thanks

[hvac1000]

Here is where your problem is. The type of system you have takes special thermostats that have a active B and O terminal. Many thermostats have the B and O terminal but you can only choose one of them to use and the thermostats you need for that zone system requires that both terminals can be used separately. This has been discussed in a few different posts on this board. The solution seems to be to use the correct thermostats or leave the old one in place.

Here is the wiring for your old thermostat.

http://customer.honeywell.com/techli...it/69-1846.pdf

A link from here with the problems associated with what you are trying to do.

https://www.askmehelpdesk.com/heatin...03-311190.html

More

https://www.askmehelpdesk.com/heatin...ir-308822.html

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https://www.askmehelpdesk.com/heatin...ng-306005.html

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https://www.askmehelpdesk.com/heatin...ls-258172.html

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https://www.askmehelpdesk.com/heatin...de-237360.html

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https://www.askmehelpdesk.com/heatin...rs-208365.html

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https://www.askmehelpdesk.com/heatin...ts-113706.html

These should give you an idea of what you are getting into.

[KISS]

Light bulb (These SHOULD work)!

T-stats having separate O & B

If the system is a HEAT PUMP, The try disconnecting O or B. It's likely that only one is needed. If the system cools rather than heats in the hat mode, then switch the other one. Otherwise, plan B might be in order.

Plan B: Use a DPDT relay to create the complement signal activated from B or O.

With heat pump systems, the thermostat controls the fan.

If the system is CONVENTIONAL/FOSSIL fuel, then connecting W/B and Y/O to W an Y of the stat respectively should work. In conventional, the furnace controls the fan.

We have a confirm that this works for Fossil fuel; https://www.askmehelpdesk.com/heatin...03-311190.html