Colder bedrooms when outside is warmer

[Althepump]

My house has basement and one floor. When outside is 7 to 10 degrees warmer than the day before, bedrooms, living room always get colder. where did the cold air come from? I am assuming cold comes from basement. I know cold air always is at bottom...heavier than warm air near the ceiling...lighter. When outside becomes warmer, cold air near the floor starts to rise and push warm air even higher. Is that reasonable that it's how I feel colder when it's warmer outside? It must have hidden somewhere unless warm air at the top becomes cold due to air molecules become less vibrant resulting colder. But it should not be because I have two windows per room.big enough for sunlight to come through. I think it has to do with ventilation.

 

[Mark44]

My house has basement and one floor. When outside is 7 to 10 degrees warmer than the day before, bedrooms, living room always get colder. where did the cold air come from? I am assuming cold comes from basement. I know cold air always is at bottom...heavier than warm air near the ceiling...lighter. When outside becomes warmer, cold air near the floor starts to rise and push warm air even higher. Is that reasonable that it's how I feel colder when it's warmer outside? It must have hidden somewhere unless warm air at the top becomes cold due to air molecules become less vibrant resulting colder. But it should not be because I have two windows per room.big enough for sunlight to come through. I think it has to do with ventilation.

I think it's a ventilation problem, as you said. However, the cold air from the basement won't start to rise just because the temperature is getting warmer outside. Maybe what's happening is that your attic isn't sealed off well from the living quarters in your house, so as the attic warms up and exits the roof, it draws cooler air up from the basement.

 

[Althepump]

I think it's a ventilation problem, as you said. However, the cold air from the basement won't start to rise just because the temperature is getting warmer outside. Maybe what's happening is that your attic isn't sealed off well from the living quarters in your house, so as the attic warms up and exits the roof, it draws cooler air up from the basement.

Your explanation is logical re: attic. Good answer. I also have another problem. I am aware that the roof ventilator is on roof. At this time, it's off, but I need to understand the basics. It has roof motor fan. Does it always exhaust/blows out warm/hot air out of the attic to outside when switch is on. The switch is right next to thermostat in living room. I know when it's on, I could see the hallway vent draws/sucks air in from the house into attic..I think from attic to its two vents to exhaust air outside while the other part of the house has another vent near kitchen blows out air (exhausts) from attic into living room. It starts air circulation. You may see now see my problem. Where does attic get/draw air into that other part near kitchen. I can see its air blowing into living room from attic. But where? How did new air get into near kitchen?

 

[Mark44]

Your explanation is logical re: attic. Good answer. I also have another problem. I am aware that the roof ventilator is on roof. At this time, it's off, but I need to understand the basics. It has roof motor fan. Does it always exhaust/blows out warm/hot air out of the attic to outside when switch is on.

The fan in the attic will blow air out of the attic whether the air in the attic is warmer than the outside air or not. The idea behind having a fan in the attic is to blow the heated air in your attic out on warm days, with the goal of keeping your house cooler on those days.

The switch is right next to thermostat in living room. I know when it's on, I could see the hallway vent draws/sucks air in from the house into attic..I think from attic to its two vents to exhaust air outside while the other part of the house has another vent near kitchen blows out air (exhausts) from attic into living room.

That seems weird to me. You shouldn't be drawing air from the attic to go into the living areas of the house.

It starts air circulation. You may see now see my problem. Where does attic get/draw air into that other part near kitchen.

The air that's blown out of the attic should come in through the other vents in the attic, not from the other parts of the house.

I can see its air blowing into living room from attic. But where? How did new air get into near kitchen?

 

[Khashishi]

Are you using a thermostat?

 

[Althepump]

You explain. It's clear now how air circulation works in the attic.

I just doubleckeck air conditioner outside. I thought when I switch on next to thermostat, the outside air conditioner fan starts. Air conditioner may work two ways.. Circulating air and a.c with freon. But it didn't happen. It did not turn on the fan at all.

I always thought the motor fan on the roof is wired to the switch next to thermostat. It appears that the roof fan has nothing to do with the switch.
The roof motor fan has to run on power wired somehow. Also it may run automatically by itself.

To make it clear, the thermostat in the hallway has its two switches.. One for cool. That's ac. I know. When on, the ac fan starts on. And the other switch is fan on.

It looks like the switch (fan on) had nothing to do with the roof fan, but when turned on, I could see air sucks air out the living room and the other Vent blows out into other part of the living room. Where is the motor fan? I now believe the small ceiling vents 1x1 foot square has ducts on top . Of them.
The air that has sucked out of living room has 24inch x 30 inch air filter, but it has no duct. mystery up in the attic?

Thank for the replies.

 

[Althepump]

Are you using a thermostat?

I have two thermostats. It's set to 62. Both. But they don't have motor fan! It bring up heat from oil furnace.

Mark, I had said about hallway thermostat. But it is not. I don't know what it is. But when house gets too warm in summer, I set to to lower temperature and ac kicks into cool the house. what's that gadget?

 

[Khashishi]

If your thermostat is on, then it changes things a lot. If your thermostat is in a less insulated part of your house, then when it is warmer outside, it will feel a warmer temperature before the rest of your house, and will adjust the heater accordingly.

 

[Althepump]

I agree with you. You are referring to air temperature. I beg apology for bringing up two different issues at the same time on same topic.
The first question is about room temperature that gets colder when outside gets warmer. Mark explains. And yours,too.

The second question is about motor fan that triggers suction and exhaustion through vents. Where is it? I may find out later.
Thank you.

 

[Mark44]

You explain. It's clear now how air circulation works in the attic.

I just doubleckeck air conditioner outside. I thought when I switch on next to thermostat, the outside air conditioner fan starts. Air conditioner may work two ways.. Circulating air and a.c with freon. But it didn't happen. It did not turn on the fan at all.

Without knowing exactly what the thermostat looks like, it's hard to say for sure. Possibly your control has one switch for heat/AC and another for fan on/off. The fan on/off switch could be used when neither the heat nor AC is on, and would just blow unheated/uncooled air.

I always thought the motor fan on the roof is wired to the switch next to thermostat. It appears that the roof fan has nothing to do with the switch.
The roof motor fan has to run on power wired somehow. Also it may run automatically by itself.

I have a fan in my attic. It's set to come on when the temp in the attic gets above 95 deg or when the humidity gets above about 90%. The fan's controls are in the unit itself -- there's no separate switch.

To make it clear, the thermostat in the hallway has its two switches.. One for cool. That's ac. I know. When on, the ac fan starts on. And the other switch is fan on.

It looks like the switch (fan on) had nothing to do with the roof fan, but when turned on, I could see air sucks air out the living room and the other Vent blows out into other part of the living room. Where is the motor fan? I now believe the small ceiling vents 1x1 foot square has ducts on top . Of them.
The air that has sucked out of living room has 24inch x 30 inch air filter, but it has no duct. mystery up in the attic?

The fan for the AC is almost certainly in the AC unit itself, which might be on the roof. I doubt that the installers would put it in the attic.

I have two thermostats. It's set to 62. Both. But they don't have motor fan! It bring up heat from oil furnace.

62 degrees? That's a very low setting. Usually people set their thermostat so the heat comes on when the temperature in the house gets below 68 to 70 degrees. People usually have their AC set to come on when the temp gets above anywhere between 70 and 75 degrees, sometimes warmer if they don't want the house to get too cool (or their electric bills too high).

Mark, I had said about hallway thermostat. But it is not. I don't know what it is. But when house gets too warm in summer, I set to to lower temperature and ac kicks into cool the house. what's that gadget?

Sounds like a thermostat.

Can you take a picture of both controls and post them here?

 

[Althepump]

Without knowing exactly what the thermostat looks like, it's hard to say for sure. Possibly your control has one switch for heat/AC and another for fan on/off. The fan on/off switch could be used when neither the heat nor AC is on, and would just blow unheated/uncooled air.
I have a fan in my attic. It's set to come on when the temp in the attic gets above 95 deg or when the humidity gets above about 90%. The fan's controls are in the unit itself -- there's no separate switch.
The fan for the AC is almost certainly in the AC unit itself, which might be on the roof. I doubt that the installers would put it in the attic.

62 degrees? That's a very low setting. Usually people set their thermostat so the heat comes on when the temperature in the house gets below 68 to 70 degrees. People usually have their AC set to come on when the temp gets above anywhere between 70 and 75 degrees, sometimes warmer if they don't want the house to get too cool (or their electric bills too high).
Sounds like a thermostat.

Can you take a picture of both controls and post them here?

I tried to upload all 4 pics. Actually three controls.
The first two picture is ac thermostat pictured from left and right. It's wired to ac unit outside. The left side is for ac and heat...but I never use heat because it's not wired at all. The right side is fan on/off. That right causes air suction into 24 x30 air filter when on. The switches are of dial mode.

The third picture is thermostat is near the kitchen.

The 4th picture is another identical thermostat in den room.

I tried to upload them all four pictures.hope it works.

Without knowing exactly what the thermostat looks like, it's hard to say for sure. Possibly your control has one switch for heat/AC and another for fan on/off. The fan on/off switch could be used when neither the heat nor AC is on, and would just blow unheated/uncooled air.
I have a fan in my attic. It's set to come on when the temp in the attic gets above 95 deg or when the humidity gets above about 90%. The fan's controls are in the unit itself -- there's no separate switch.
The fan for the AC is almost certainly in the AC unit itself, which might be on the roof. I doubt that the installers would put it in the attic.

62 degrees? That's a very low setting. Usually people set their thermostat so the heat comes on when the temperature in the house gets below 68 to 70 degrees. People usually have their AC set to come on when the temp gets above anywhere between 70 and 75 degrees, sometimes warmer if they don't want the house to get too cool (or their electric bills too high).
Sounds like a thermostat.

Can you take a picture of both controls and post them here?

 

[Mark44]

I tried to upload all 4 pics. Actually three controls.
The first two picture is ac thermostat pictured from left and right. It's wired to ac unit outside. The left side is for ac and heat...but I never use heat because it's not wired at all. The right side is fan on/off. That right causes air suction into 24 x30 air filter when on. The switches are of dial mode.

This one is pretty much as I described, with a switch on one side for heat/cool and a switch on the other side for fan on/off.

The third picture is thermostat is near the kitchen.

The 4th picture is another identical thermostat in den room.

Since the thermostat in the first two pictures isn't wired to the furnace, probably the one in the third picture is wired to the furnace. The thermostat in your den might be to an electric baseboard heater or a wall heater of something. I don't think you can have two thermostats controlling one furnace.

Have you ever been up on your roof? I'm betting that's where the AC unit is. And if you notice air coming out of the ductwork, it doesn't seem likely to me that it's coming from the attic. Instead, I'm guessing that it flows through ducts in your attic. Did you just recently move into this house? It doesn't sound like you're very familiar with it or its workings.

 

[Althepump]

This one is pretty much as I described, with a switch on one side for heat/cool and a switch on the other side for fan on/off.

You are accurate in describing it before seeing it>

Since the thermostat in the first two pictures isn't wired to the furnace, probably the one in the third picture is wired to the furnace. The thermostat in your den might be to an electric baseboard heater or a wall heater of something. I don't think you can have two thermostats controlling one furnace.
You are correct!Have you ever been up on your roof? I'm betting that's where the AC unit is. And if you notice air coming out of the ductwork, it doesn't seem likely to me that it's coming from the attic. Instead, I'm guessing that it flows through ducts in your attic. Did you just recently move into this house? It doesn't sound like you're very familiar with it or its workings.

This one is pretty much as I described, with a switch on one side for heat/cool and a switch on the other side for fan on/off.
Since the thermostat in the first two pictures isn't wired to the furnace, probably the one in the third picture is wired to the furnace. The thermostat in your den might be to an electric baseboard heater or a wall heater of something. I don't think you can have two thermostats controlling one furnace.
Yes, correct. But The third and fourth picture are two thermostats connected to the same oil furnace in the basement.

Have you ever been up on your roof? I'm betting that's where the AC unit is. And if you notice air coming out of the ductwork, it doesn't seem likely to me that it's coming from the attic. Instead, I'm guessing that it flows through ducts in your attic. Did you just recently move into this house? It doesn't sound like you're very familiar with it or its workings.

After some exchanges, I began to realize that you are correct about the ductwork. It's flowing through ducts in my attic; not from the attic. No, it's old house.
I am not familiar with its workings because I am deaf and dumb.

No, I have never been up on the roof. You think it's where AC unit is...but I always thought the unit is outside in front of the kitchen because it has big fan... Looks like horizontal propeller. What is that housing with fan outside doing in front of the kitchen if you think AC unit is on the roof? Can it be possible to have both? I will identify that housing tomorrow. It's already dark. And let you know.

 

[Mark44]

No, I have never been up on the roof. You think it's where AC unit is...but I always thought the unit is outside in front of the kitchen because it has big fan... Looks like horizontal propeller. What is that housing with fan outside doing in front of the kitchen if you think AC unit is on the roof? Can it be possible to have both? I will identify that housing tomorrow. It's already dark. And let you know.

That sounds like the AC unit. I don't think you mentioned it before, so I thought it might be on the roof. I doubt that there are two AC units.

 

[Althepump]

Right, I never mentioned ac unit on the roof. I had said ventalitor.. Anyway the ac unit on the roof you suggested may be attached via ductwork to housing outside to exhaust hot air. I will take another look at the housing tomorrow morning. I think you solved it.

The surrounding air in the attic not inside ducts has to be ventalited, too but this is another thing. I thought it was already solved, I will let you know tomorrow.

 

[Althepump]

Two pics.. The first one is AC because no ducts are attached to it. When AC is turned on, I could feel hot air coming out from the top of the AC.
The second one is the label for AC.

I will take another pic later of the roof. The sun glare right now is too strong.

I have an appt for AC annual maintenance on April 4th. I will ask him what it is on the roof and update for those who are interested.
Also, I will ask him if it's AC and also attached to ductwork underneath.

 

[Althepump]

Added comment:

After reviewing AC (refrigerator) basics, the AC has condenser coils inside throws out hot compressed air from coolant i.e. freon. on the condenser fins. It has to go compressor first before that happens. The coolant now gets little cooler after throw it out then go through expansion device to expand coolant further to make the coolant cold further at low temperature then through evaporator coils in the attic with cold coolant inside. The hot air linside the attic are absorbed to the evaporator coils make air in attic cooler. The absorbed hot air inside the coolant now warm. It then goes to compressor to get very hot on way to condenser coils. And the cycle repeats.

The basics help me get general understanding.

I am uploading a picture of the roof. It's not close up, but you may see like a small black hat on the top roof. The others on right belongs to chimney. not related to this topic. By now I think it (black hat) has nothing to do with AC. It's separate by itself.i believe there is a "evaporator" unit somewhere in the attic that couples with AC outside.

I will find out on April 4th. Thank you guys for the help.

 

[russ_watters]

So, are there supply and return air vents in your bedrooms? You should feel the cold air coming out...

The evaporator (and fan) aren't there to cool the attic, they are there to send cold air into the house through ductwork. It is not uncommon though for there to be a single large return (not an exhaust) in a central hallway.

It sounds like you have been air conditioning your house (really cold!) without realizing it. Your electric company must be thrilled.

 

[Khashishi]

62 degrees? That's a very low setting.

It's totally reasonable if you are tough and want to save energy during the winter. I don't even bother with heating unless it's near freezing.

 

[Althepump]

Yes, you are correct that evaporator has to send cold air through ductwork in the attic. Not to cool the attic or the house will be drowned with bills. I thought it's obvious...not necessary to mention it. Thank for the reminder. I have to be more careful next time.

Yes, the supply vent is in the living room, all bedrooms just have return vents. Looks like 6 return vents and 1 supply vent. Maybe 2. Another one is in family room. I will check f.r. Later. You ask an excellent question. Oh I forget about the 24x30 " filter. I guess it's another return vent, but bigger than the register sized vents. That 24x30 does not have duct. Can I call it return vent?

Re: billing.. I use AC very seldom during the summer. Maybe twice. 2 days in total. Very little, but annual contract is lots more expensive. Nothing I can do.

Nevertheless, I just learned that AC can be used as heater in the winter from YouTube videos. But mine is not. Just AC for the summer.

 

[russ_watters]

Yes, the supply vent is in the living room, all bedrooms just have return vents. Looks like 6 return vents and 1 supply vent.

That would be highly unlikely unless the unit is ducted backwards. The bedrooms have to have supplies and the 24x30 has to be the return.

That 24x30 does not have duct. Can I call it return vent?

Sometimes the walls themselves are used as ducts. The space between the studs is 14"x4" and can carry the airflow from several rooms.

Re: billing.. I use AC very seldom during the summer.

Based on what you are describing, it sounds like you have been accidentally running it a lot in the winter/spring, with a very low setting of 62F.

 

[Althepump]

Correction:

All bedrooms (2) have each supply vent. Den 1 supply vent, bathroom 1 supply vent, hallway 1 supply vent, living room 3 supply vents,
Kitchen 2 supply vents, family room 1 supply vent and only 24x30" air filter in same hallway has one return vent.

Total 11 supply vents and one return.

 

[Althepump]

That would be highly unlikely unless the unit is ducted backwards. The bedrooms have to have supplies and the 24x30 has to be the return.

I just made a correction post. Your correct! All bedrooms are supply vents. The correction posting gives more details.

Sometimes the walls themselves are used as ducts. The space between the studs is 14"x4" and can carry the airflow from several rooms.
Interesting! I don't know other alternative to wall ducts because when I open the air filter. All I ca see is open attic.

Based on what you are describing, it sounds like you have been accidentally running it a lot in the winter/spring, with a very low setting of 62F.

the 62 degrees is set on both thermostats that are wired to furnace in the basement. The furnace has two different water pipes. Each pipe for each thermostat. I believe. I don't see how it can cause lots of heat. When the living room temperature goes above 62, the water baseboard stops give off heat from furnace downstairs. When it drops below 62..say 55, the water baseboard turns on giving heat until 62 and stops. The heat generated only to first floor. No heat in attic.
Maybe I should set to 68.

There is third thermostat in hallway that's wired to AC outside. This thermostat acts in opposite. If set to 72 while the ambient surrounding air in living room is 80... It will turn on AC and bring cool to the living room until it hits 72 degrees then stops.

That AC is not wired for heating purpose. And I don't use AC in winter/ spring. Never touched it. How does it possible to run it a lot in winter/spring?

 

[Althepump]

It's totally reasonable if you are tough and want to save energy during the winter. I don't even bother with heating unless it's near freezing.

I think Mark is correct about billing. When set to 62, it can be very low because when it goes few more degrees below, it causes furnace to generate a lot of heat until it hits 62. If the setting is at 70 instead and drops a few degrees below, it will generate much less amount of heat until 70. much less than when set to 62

But I spend so much in my bedroom with an electric space heater with door closed. I may be cheating my electric company. Don't tell.

 

[Althepump]

This one is pretty much as I described, with a switch on one side for heat/cool and a switch on the other side for fan on/off.
Since the thermostat in the first two pictures isn't wired to the furnace, probably the one in the third picture is wired to the furnace. The thermostat in your den might be to an electric baseboard heater or a wall heater of something. I don't think you can have two thermostats controlling one furnace.

Have you ever been up on your roof? I'm betting that's where the AC unit is. And if you notice air coming out of the ductwork, it doesn't seem likely to me that it's coming from the attic. Instead, I'm guessing that it flows through ducts in your attic. Did you just recently move into this house? It doesn't sound like you're very familiar with it or its workings.

It's totally reasonable if you are tough and want to save energy during the winter. I don't even bother with heating unless it's near freezing.

Mark is correct. I spend a lot in my bedroom with door closed; electric space heater on. I am cheating electric company. Re billing..I think it costs more money leaving thermostat at 62 instead of 68 or 70. When it's colder say 1 degree below 62, the furnace will deliver lots of more heat energy until 62 then stops. Lots more than set at 70. When 1 degree below 70, it will generate heat until 70, but much less heat than 62 setting. More bills at 62. Maybe after all electric co outfoxes me.

I will set to 68 or 70 from now on.

 

[Althepump]

the 62 degrees is set on both thermostats that are wired to furnace in the basement. The furnace has two different water pipes. Each pipe for each thermostat. I believe. I don't see how it can cause lots of heat. When the living room temperature goes above 62, the water baseboard stops give off heat from furnace downstairs. When it drops below 62..say 55, the water baseboard turns on giving heat until 62 and stops. The heat generated only to first floor. No heat in attic.
Maybe I should set to 68.

There is third thermostat in hallway that's wired to AC outside. This thermostat acts in opposite. If set to 72 while the ambient surrounding air in living room is 80... It will turn on AC and bring cool to the living room until it hits 72 degrees then stops.

That AC is not wired for heating purpose. And I don't use AC in winter/ spring. Never touched it. How does it possible to run it a lot in winter/spring?

Now I see your point about using a lot of winter/ spring. Please read my comment to khashishi in his reply to mark about braving in low 62.
You are correct.

 

[Althepump]

This one is pretty much as I described, with a switch on one side for heat/cool and a switch on the other side for fan on/off.
Since the thermostat in the first two pictures isn't wired to the furnace, probably the one in the third picture is wired to the furnace. The thermostat in your den might be to an electric baseboard heater or a wall heater of something. I don't think you can have two thermostats controlling one furnace.

Have you ever been up on your roof? I'm betting that's where the AC unit is. And if you notice air coming out of the ductwork, it doesn't seem likely to me that it's coming from the attic. Instead, I'm guessing that it flows through ducts in your attic. Did you just recently move into this house? It doesn't sound like you're very familiar with it or its workings.

It's totally reasonable if you are tough and want to save energy during the winter. I don't even bother with heating unless it's near freezing.

Mark, right. Temp setting 62 too low causes more heat to generate than 70. More billing.

 

[Althepump]

So, are there supply and return air vents in your bedrooms? You should feel the cold air coming out...

The evaporator (and fan) aren't there to cool the attic, they are there to send cold air into the house through ductwork. It is not uncommon though for there to be a single large return (not an exhaust) in a central hallway.

It sounds like you have been air conditioning your house (really cold!) without realizing it. Your electric company must be thrilled.

You' right. Setting at 62 too low. ...generate more heat when 1 degree below 62 than 1 degree below 70. Therefore, more $$$. Now I set to 68. Or 70. electric co will not be so thrilled any more. Thanks.

 

[russ_watters]

the 62 degrees is set on both thermostats that are wired to furnace in the basement.

No, you can't have two thermostats wired to the same furnace. The thermostat in the hallway is a heating and cooling thermostat and it is almost certainly wired to the "furnace" in the attic. The evaporator coil is for the air conditioning and is attached to the furnace in the attic and uses the furnace fan to circulate the air.

The furnace has two different water pipes. Each pipe for each thermostat. I believe.

Furnaces don't have water pipes, they have 3/4" gas or oil pipes and they have ~3" combustion exhaust ducts that are sometimes made of pvc piping material. The word "furnace" referring a device that burns fuel to heat air. If you have a boiler, and you really have two water pipes going into the air handling unit (are they insulated?), one would be the supply and the other the return.

I don't see how it can cause lots of heat. When the living room temperature goes above 62, the water baseboard stops give off heat from furnace downstairs. When it drops below 62..say 55, the water baseboard turns on giving heat until 62 and stops...
Maybe I should set to 68.

Right, 62F is the heating setpoint -- but it looks to me like it is also the cooling setpoint. I can't tell from the pictures if the thermostat automatically changes between heating and cooling. Between "heat" and "cool" is there an "auto" that it is set for? Or just "off"?

The heat generated only to first floor. No heat in attic.That AC is not wired for heating purpose.

I think it is. I can see in your first picture, the pointer in the upper left has options of "heat" and "cool". I think the unit in the attic has heating and cooling because the thermostat indicates it is for a unit that has both heating and cooling.

And I don't use AC in winter/ spring. Never touched it. How does it possible to run it a lot in winter/spring?

By leaving it set in "auto" it will change between heating and cooling on its own. Or just accidentally turning it on and not realizing that it is both a heating and cooling thermostat.

It isn't difficult to tell what a system is doing: if air is coming out of the supply vents, it is on. If the air is warm, it is heating and if the air is cold, it is cooling. And when it is cooling, the condenser outside will be on/make noise.

It might be worth having a friend who knows about such things - or even getting a contractor - to come and poke around, looking at your equipment to tell you what you have. It isn't easy to tell from the limited and confused information you are able to tell us.

 

[Althepump]

No, you can't have two thermostats wired to the same furnace. The thermostat in the hallway is a heating and cooling thermostat and it is almost certainly wired to the "furnace" in the attic. The evaporator coil is for the air conditioning and is attached to the furnace in the attic and uses the furnace fan to circulate the air.

I cannot say your wrong...but I need to tell you that basement furnace has two water pumps. That's why I believe each thermostat is wired to each pump. If one thermostat is set higher than the other one. Then the pump will pump out more than the other pump. I word it...water pipes wrong.. I know the furnace is connected to copper pipes with hot water in it to baseboards upstairs on first floor. Baseboards give off heat in baseboards' fins. Then cold copper pipes return to the furnace again. Its all I know. One other thing I think I learn right that the burner (flame) inside is always on whether or not hot water is used.
It is possible I learn wrong.

Furnaces don't have water pipes, they have 3/4" gas or oil pipes and they have ~3" combustion exhaust ducts that are sometimes made of pvc piping material. The word "furnace" referring a device that burns fuel to heat air. If you have a boiler, and you really have two water pipes going into the air handling unit (are they insulated?), one would be the supply and the other the return.

You say furnace burns fuel to heat air. I may learn wrong.

Now I see what you mean. Yes, the furnace heats air via duct on top. I don't know what it's for. Maybe I can say it's duct for ac? I have to say I am lost.
The furnace has oil pipes connected to the right side just to feed burner with flame inside on where water go through via copper pipes to become hot.
The way you say it sounds like I have two things: furnace/boiler in one big unit. Very old over 25 yrs.

Right, 62F is the heating setpoint -- but it looks to me like it is also the cooling setpoint. I can't tell from the pictures if the thermostat automatically changes between heating and cooling. Between "heat" and "cool" is there an "auto" that it is set for? Or just "off"?
The thermostat in hallway is just fixed for AC only. Although it has separate dial for heat, it is never used. If I turn it on..nothing happens.
It's not wired for heat because the central AC installer years ago knows I have two other thermostats in den and living room that are used for heating only.

If I set to auto, it will turn on AC for cooling purposes. It will cool the house. Evaporator coils some where in attic makes air cool on first floor.
I always set it off instead of auto. When set off nothing happens. Also on the same thermostat has another dial fan on or off. When I turn fan on, I could feel the ventaliation (air circulating) maybe even more if windows open and door open. Just nice air breeze circulating. I can feel the supply vents blowing just air and the return vent draws air into it. That's all there is to it. You may notice fan on and fan off. When I don't need fan, then I turn it off. The off is the same as fan off.I think it is. I can see in your first picture, the pointer in the upper left has options of "heat" and "cool". I think the unit in the attic has heating and cooling because the thermostat indicates it is for a unit that has both heating and cooling.

By leaving it set in "auto" it will change between heating and cooling on its own. Or just accidentally turning it on and not realizing that it is both a heating and cooling thermostat.
I agree that it should change between heating and cooling. But it's not.. No heat ... Maybe I am not realizing its both a heating and cooling element. Maybe ignorant. You are preparing me well and I will ask all those intellectual questions when the maintenance comes on April 4th.

Maybe I am duped in believing that that thermostat is just for AC only even though has heat and cool dials.

It isn't difficult to tell what a system is doing: if air is coming out of the supply vents, it is on. If the air is warm, it is heating and if the air is cold, it is cooling. And when it is cooling, the condenser outside will be on/make noise.

I will check it. I will try Heat again, but remember I told you about two other thermostats. There in whole.

It might be worth having a friend who knows about such things - or even getting a contractor - to come and poke around, looking at your equipment to tell you what you have. It isn't easy to tell from the limited and confused information you are able to tell us.

Ok on April 4th. He or the contractor. I am now lots better prepared with questions for him.