Thermostat placement

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    I have a Tri-level home with two separate furnaces and air conditioning units. One unit controls the lower two levels and another the upstairs level. The lower unit has a thermostat located at the bottom of the stairway leading to the upstairs, and the upstairs had a thermostat at the TOP of those stairs.
    Ever since I moved into this home (30+ years ago), I have had uneven heat/cooling of the upstairs rooms. When the heat or cooling would go on, the room temperature would be some 8-10 degrees different from what the thermostat was reading. Eventually the thermostat would be effected by the temperature change and would turn off the heat or AC. The only problem was it ran much longer when it would come on, and the uneven room temperatures.
    Recently I read that a thermostat should NOT be installed at the top of a stairs. Obviously heat from the downstairs would tend to rise and impact on the upstairs thermostat when cooling was taking place. The question I have is why the uneven control while heating is taking place? One would think that when the upstairs furnace was on, the stairs would have little or no impact due to the heat rising up?
    Finally I decided to do something about this uneven temperature problem. I took a digital thermometer and looked for a location in the same hallway upstairs that was more representative of the true temperature. That is, much warmer than being sensed by the thermostat. After relocating the thermostat some 10 feet away from the stairs the temperature is much more even. I am very happy with the result.
    My question is this: I can understand the impact of the stairway on cooling the upstairs, but why did the heating of the upstairs respond poorly as well? I feel I am overlooking something simple, since I know it DOES impact it by the results I achieved.
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You have poor molecular acceleration of the electrons in the air due to improper placement of the two heating/cooling systems. Both systems need to be removed from the home and reinstalled so they both have a center point of balance in the home. Next you need to clean and sanitize the ductwork in both systems. Next have an airflow company come in and balance both systems. Next have the thermostat wiring replaced with new wiring. While doing the wiring, replace the thermostats so the electron particles of the 24 volt system mimic the particles of the new stats. All of this should give you a well operating system. Bubba
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Bubba wrote:

Dear Bubba,
    I appreciate your in depth analysis of my question, and I feel obligated to repay you with my diagnosis of YOU. You should immediately gather up ALL the laxatives available to you, and take them. It is obvious that you do not have a job, and perhaps the reason is that your shit level has reached your brain. Taking those laxatives will certainly add a lot to your posts, and who knows, it might allow you to find the unemployment office or a place of employment?? I sure hope Obama has a program that can help people like you.
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Ken wrote:

Install a door at the bottom of the stairs.
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<<//--------------------\>>
Van Chocstraw
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A lot depends on the air currents too. If you have heat pouring into the rooms and nothing hitting the thermostat, it will be very slow to respond. You can also get cold air currents going by the thermostat and down the stairs too.
Light a candle and stand in the stair well. Move the candle from floor to ceiling and watch the flame. You'll suddenly understand a lot.
Ed
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I have a large central open staircase. At the top of the stairs is a cold air return and 4 feet about it is a thermostat for the upper floors. The first floor thermostat is about 4' above the bottom cold air return. The two systems work independently, but both themostats are on inside walls. I grew up in a house where the thermostat would kick on when the front door was opened during the winter. You may want to have the blower on all the time, or ceiling fans, or an extra fan to circulate the air. All homes have hot-cold pockets, but you can minimize that with fans, draperies, furniture, etc.
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Phisherman wrote:

    First I would like to thank you and others who replied with helpful comments. As I wrote in my original message, moving the thermostat improved the situation dramatically. I am sure the fact the old location was directly above the stairs was largely responsible for its poor performance. It is easy to visualize how the warm air of the lower floor would travel up the stairs and impact that thermostat when cooling was taking place. What puzzled me is why there was still a problem when furnaces were being used. One would think that the heat rising from the lower floor would turn off the upstairs thermostat earlier, rather than later.
    As Ed suggested, there has to be air currents effecting the old location because moving the thermostat's location solved the problem. I guess I should just be happy the problem was solved, but I like to understand WHY something happened. Thanks.
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Do you know what is behind the wall where the upstairs stat was mounted?
They say you shouldn't mount a stat on an outside wall since they are typically colder than the air in the room. Is it possible that the wall itself could be affecting the stat?
At the top of my stairs I have an access panel for the tub. This cavity is open from the basement to the attic and typically colder than the surrounding air.
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DerbyDad03 wrote:

    Just a bedroom. There is no unusual temperature factor behind either location to effect what the thermostat would read.

    A good point, but that is not the case here. It really seems to be the fact that it was at the top of the stairs, for if I took a thermometer elsewhere in the hall the temperature would be more nearly that of the rooms being heated. Again, there could be some unusual air currents in that area that are unrelated to being at the top of the stairs, but it definitely worked better when moved.

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As an inspector, I recall a guy that was dealing with such issues. He put a bathroom vent fan at the second floor ceiling, blowing into the open wall cavity. He had also cut an opening at floor level in the wall. So there was an uninterrupted path to the wall cavity on which the thermostat was mounted. The thermostat was a temperature setback unit, with its sensing thermistor at the lower rear portion. He had a small hole behind the temperature sensor, and all it really sensed was the temperature of the air from the second floor. Yeah, this guy acknowledged being on medication for his OCD.

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Michael B wrote:

    Another good point. I even went so far as to plug up the hole that the thermostat wires were coming through, thinking much like the example you gave. I thought a draft of sort might be coming from the attic effecting the thermistor like you cited.

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I am only guessing, put the thermostat in a room like the bedroom, halls are drafty. Heat rises, cool AC air falls so summer will be different by alot. The thermostat can be calibrated for temp reading if it is wrong and an anticipator setting on many or swing temp setting can make heat more even. Factory settings are a start point to your comfort. Wasnt Bubba the Hvac pro helpfull.
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ransley wrote:

    I guess it is all a moot point now, since the problem has been solved. I did not mention it before, but when I was playing with the digital thermometer I took it to the area where the thermostat originally was located and it was reading the same temperature. This was done to ascertain if the thermostat was reading true. When I found another point in the hallway that was closer to the temperature in the bedrooms, I decided to move the thermostat.
Wasnt Bubba the Hvac pro helpfull.
    Yes, he was helpful. Like a dose of the Clap!! Guys like him wonder why people are reluctant to call them for help. They don't exactly exude confidence.
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Not to be the grammar police, but indeed he "exudes" confidence. But does not 'elicit' or 'encourage' that same confidence from others.
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Someone else said this better than me.
"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts." -- Bertrand Russel
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Ahem....better than "I".
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Hey Ken, You sound jealous but then I can see why. My dual fuel system I installed works wonderful. Its nice and warm and even throughout the house. Its also fairly inexpensive to operate. Strange how that happens. All the systems I install have a way of working like that. Gee.......how can that be possible? Im so sorry to hear that yours isnt working the way it should. It seems you had the cheapest hack install yours. As they always say, "You get what you pay for". You an ransley certainly make a cute couple. Bubba
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You are soo helpfull. To bad you know little about what alot of the US uses, Boilers. I guess in cabin land your dual fuel is a must, is that wood and coal?.
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On Fri, 16 Jan 2009 16:41:17 -0800 (PST), ransley

What I know about hot water and steam boilers would make your head swim. What you know I could easily fit in a thimble and still have room left over. Have you actually seen an efficient boiler? Just installed a Lochinvar Knight. Awesome and the customer loves it. Went from $800 a month to just barely under $400. Damn, I sure wish I knew what the hell I was doing. Poor ransley......maybe someday you will grow up to be somebody or something other than a little piss-ant. Bubba
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Bubba wrote:

    I am sorry that your ability to read and comprehend is so poor. If you will re-read my post you will see, "After relocating the thermostat some 10 feet away from the stairs the temperature is much more even. I am very happy with the result."
    I suspect you do not listen to customers any better than you do to people posting on the news groups.
It

    No, quite the contrary. The units were installed by professional HVAC people who claim to have been licensed. Are you licensed??? If so, perhaps you attended the same classes they did and might be alumni?
    PLEASE take the laxatives, for I would hate to read in the paper that someone died due to a shit head explosion and ruined a nearly full bag of chips and an open can of beer!!
You an ransley certainly make a cute

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