Carrier A'cond/furnace MOD.

[ctpres]

Not real happy with temp control in heating mode. Figure problem due to ceiling mounted thermostat. Studied man. and furnace control connection is just two wire on/off. Anyone know why I can't install wall mount, battery powerd digital thermostat using those wires at furnace? Side benefit: will be ability to run ceiling unit fans for better air circulation when furnace is running, something you can't do in normal furnace node.

[jcthorne]

It can be done. There is also provision in the Carrier to connect a remote wall mounted thermal sensor, just another option.

[powerboatr]

Quote:

Originally Posted by ctpres Not real happy with temp control in heating mode. Figure problem due to ceiling mounted thermostat. Studied man. and furnace control connection is just two wire on/off. Anyone know why I can't install wall mount, battery powerd digital thermostat using those wires at furnace? Side benefit: will be ability to run ceiling unit fans for better air circulation when furnace is running, something you can't do in normal furnace node.

i like the idea of some more air circulation with the heater on
post up your fix and pics.
sounds like a good plan
i turn the rear unit ceiling unit on to move air, when the furnace is on .

[DiamondDan]

Quote:

Originally Posted by jcthorne It can be done. There is also provision in the Carrier to connect a remote wall mounted thermal sensor, just another option.

Do you have a part number or other reference for this option?
Thanks.

[jcthorne]

Quote:

Originally Posted by DiamondDan Do you have a part number or other reference for this option? Thanks.

The Carrier part number for the wired wall mounted temp sensor is 99-00469-37. Its only a two wire connecton to terminals in the ceiling unit, essentially replacing the thermistor on the ceiling with one on the wall.

[max49]

I put a wall thermostat in too. My Carrier thermostat would only go down to 63* . The wall one goes down 45*. I can control the heat with either thermostat. The hardest part was running the wires under the the coach because the furnace is on the opposite side of the hall where I wanted to mout the thermostat.

[wrongagain]

I know I'm new here but let me say I have been in the hvac biz for over 30 years.
Any 2 wire system is just a simple make-break type circuit.
If you wanted you could just touch the wires together and all will work in a pinch, of course you wont have temp control but the unit will work, and you would have to rely on yourself to disconnect the wire to regulate temp.
I do it all the time on the jobs to make heat for the plasterers or painters, so the new thermostats don't get destroyed before the final walk thru.
That being said there are a bunch of manufacturers right now making remote control "wireless" thermostats.
You do not need to buy carrier thermostats, all thermostats will work.

[jcthorne]

The Carrier roof mounted ac IS a wireless control system with the temp sensor and logic in the ceiling mounted unit. It is not wired like a conventional thermostat in the home. I know of no other wireless thermostats that can communicate with the carrier unit. Carrier does make a remote mount temp sensor but its just a thermistor for remote mounting, not the controls.

If you know of a wireless thermostat that works with the carrier roof ac, please let us know.

Carrier does have a hard wired type unit but its a different logic board and connections that the wireless unit that Damon installs.

[jcthorne]

Just FYI, the newer carrier units go down to 45 deg on the heat setting. Change happend in 06 or 07. Replacement remotes have this functionality too.

Quote:

Originally Posted by max49 I put a wall thermostat in too. My Carrier thermostat would only go down to 63* . The wall one goes down 45*. I can control the heat with either thermostat. The hardest part was running the wires under the the coach because the furnace is on the opposite side of the hall where I wanted to mout the thermostat.

[max49]

Quote:

Originally Posted by jcthorne Just FYI, the newer carrier units go down to 45 deg on the heat setting. Change happend in 06 or 07. Replacement remotes have this functionality too.

I know this, in fact, Carrier sent me a new remote that goes down to 45* and the part I needed to change at the unit, but it still came on at 63*. Carrier didn't charge me so I just installed the wall unit. It works good and tells me the temp inside the MH.
I don't know what they were thinking when they put the min temp at 63*. That's my max. and at nite I put it down to about 46*. Cold is great for sleeping.

[lllkrob]

Completed "rewiring" my Atwood furnace to operate independently of the front Carrier A/C temp control. Simply cut the blue wires coming from the A/C unit and wire in a Sky Tech wireless receiver and Sky Tech 3301P wireless programmable thermostat. No wiring to chase under cabinets or through walls. The equipment was a little expensive, $115.00, but the time and frustration saved was priceless. Now I can program the furnace to come on at 7:00 AM warm the coach to 72 degrees at 9:00 it will set the furnace back to 65 degrees for the day then back to 72 for the evening and 60 at night. This setup works for the furnace only not the A/C. That still uses the Carrier remote.