Thermostat question

[Cheri]

When the air conditioner is running, should the thermostat be set to auto or cool? My friend says auto, I say cool...anyone know for sure, and what is the difference. Thanks.

-- Cheri

[jmeehan]

That depends on the thermostat. Do you have the instructions for the one you have? If not likely you can find a copy on line by searching for the specific model number and name. Is this a thermostat for a central system or a window unit?

My guess is either will result in the same result. Auto is likely the name used for the setting that will automatically shift between heating and cooling. It the interior temperature is above the set cooling temperature it will cool if the temperature is below the heating set temperature it will start heating. That should not be likely this time of year. In between nothing happens.

Some window or single room air conditioners have an auto that means it will turn off and one to maintain the set temperature and the cool button will cause it to stay on cool even if it is 40=BA.

[Cheri]

TY for the info.

Cheri

My guess is either will result in the same result. Auto is likely the name used for the setting that will automatically shift between heating and cooling. It the interior temperature is above the set cooling temperature it will cool if the temperature is below the heating set temperature it will start heating. That should not be likely this time of year. In between nothing happens.

Some window or single room air conditioners have an auto that means it will turn off and one to maintain the set temperature and the cool button will cause it to stay on cool even if it is 40º.

[RickH]

With most thermostats the Auto setting is part of the fan switch like this: On/Auto. And heat/cool is part of the system mode switch like this: Cool/Off/Heat

So your fan switch should be on Auto and the heat/off/cool switch should be on Cool.

I suppose there are thermostats smart enough to measure the outside temp and decide if your system should be on cool (ac mode) or heat (furnace mode) based on target temp vs outside vs current inside temp, but for a typical residence I would doubt that you have such a thermostat.

So set the switches to Auto and Cool for AC and this winter set it to Auto and Heat, the only time you would not run Auto is if you want to run the system air handler manually for some reason.

[Cheri]

TY

So your fan switch should be on Auto and the heat/off/cool switch should be on Cool.

I suppose there are thermostats smart enough to measure the outside temp and decide if your system should be on cool (ac mode) or heat (furnace mode) based on target temp vs outside vs current inside temp, but for a typical residence I would doubt that you have such a thermostat.

So set the switches to Auto and Cool for AC and this winter set it to Auto and Heat, the only time you would not run Auto is if you want to run the system air handler manually for some reason.

[ransley]

Mine is set to cool - auto. But you can set yours to heat if you wish.

[Tony Hwang]

Hi,

3 settings you can choose. Cool for cooling only, Heat for hating only. Auto for cooling or heating whichever case it may be. Also Fan has 3 settings. Auto, On, Off.

[Tony Hwang]

You mean system setting >> Cool, Fan setting >> Auto.

[Mark Lloyd]

My thermostat has an 'auto' mode on the system switch (which is something completely different from the 'auto' on the fan switch). I don't use it because it doesn't have separate temperature settings for heat and cool, and I like setpoints about 8 degrees apart rather that the 2 the 'auto' mode uses.

[Mark Lloyd]

That would allow you to run the compressor without using the fan. Isn't that a bad thing to do?

[RT]

You sure you can't change it ? I am planning to buy a venstar thermostat and it has an option to change it

[Mark Lloyd]

[snip]

The particular thermostat I have may not have an option to change it (although it's an electronic thermostat, so it wouldn't be that hard for them to add that feature). There may be a way. Maybe I'll find it now. Thanks.

[Andrew Sarangan]

Does anyone know a thermostat that can be controlled by a computer, not wireless, but wired, such as RS232?

[mm]

I don't. Without a brand name, I don't even know what RS232 means. (Is that phone jack lingo?)

Call a heating and AC supply house. They'll sell to you if you know what you want and don't waste too much of their time, and in this case, they'll probalby sell to you just because so few people are buying such things from them. Heck maybe they sell anything to anybody, maybe not, I don't know.

But if you do find one, you'll still need another thrermostat set at a minimum temperature, so that if your computer reboots or crashes or whatever, there is something to keep the temp of the house from going too low, unless it never gets that cold.

[Bubba]

Real big on Google searches are you? Your fries are coming right up with that order. Bubba

[Mark Lloyd]

RS stands for "Recommended Standard", and is an old standard for serial communications (ALL modems used to use it).

BTW, it has nothing to do with Radio Shack, which I thought at one time.

Unless the thermostat regulates temperature itself. That is, if it isn't actually a thermostat but just a collection of relays.

[dpb]

Andrew Sarangan wrote: ...

Google could be your friend...

"serial thermostat" returned 690k w/ most of the first page what appear to be pertinent results.

These days, altho I've not looked, I'd suspect there would be USB interfaces even more common and possibly less expensive.

--

[dpb]

Then a google would answer the question very quickly...

He didn't ask for a computer-control, but a computer-controlled thermostat. All that's lost w/o the computer is the remote control feature.

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