DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   General DIY Discussions (http://www.diychatroom.com/f2/)
-   -   Home heating inconsistencies (http://www.diychatroom.com/f2/home-heating-inconsistencies-128876/)

J187 01-05-2012 07:59 AM

Home heating inconsistencies
 
I struggle with the temps a bit in my home. One problem I see, is that the house often feels very different from what the thermostat reads. If I turn my heat up to 70 when I come home from work, the heat will come on and run for a little while until the thermostat reads that it is 70. Then the heat will shut off. It feels warm and everything seems ok. The problem is that it doesn't SEEM that the thermostat registers quickly enough that the temp is dropping over time. An hour later, the thermostat still reads 70 and the heat stays off, but the house starts to feel more like 67. I don't really know much about heating systems to identify A. Whether or not this is a common problem or B. What might be the cause. It seems to me that the thermostat being in a narrow in the center of the house will definitely read slightly different temps than what would be true of the rooms with exterior walls toward the sides of the house. But this seems like a significant discrepancy. Any thoughts?

I will get a stand alone thermometer today and measure the temps throughout the house and see if they match up to the thermostat.

DangerMouse 01-05-2012 08:37 AM

If your thermostat were near to the floor, it would not do that. Heat rises, cold air sinks, therefore the thermostat won't feel the cooler air until it reaches that height..... but of course, you do.

DM

DrHicks 01-05-2012 09:50 AM

Quote:

Originally Posted by J187 (Post 813078)
I struggle with the temps a bit in my home. One problem I see, is that the house often feels very different from what the thermostat reads. If I turn my heat up to 70 when I come home from work, the heat will come on and run for a little while until the thermostat reads that it is 70. Then the heat will shut off. It feels warm and everything seems ok. The problem is that it doesn't SEEM that the thermostat registers quickly enough that the temp is dropping over time. An hour later, the thermostat still reads 70 and the heat stays off, but the house starts to feel more like 67. I don't really know much about heating systems to identify A. Whether or not this is a common problem or B. What might be the cause. It seems to me that the thermostat being in a narrow in the center of the house will definitely read slightly different temps than what would be true of the rooms with exterior walls toward the sides of the house. But this seems like a significant discrepancy. Any thoughts?

I will get a stand alone thermometer today and measure the temps throughout the house and see if they match up to the thermostat.

There are a lot of variables that could cause this - everything from the location of the thermostat, to a battery being low (if it's programmable), to the thermostat simply needing to be replaced.

If you have drafty windows & doors and/or poorly insulated house, and the thermostat is in the middle of the house (which is where they usually are), the rest of the house can get pretty chilly before the thermostat kicks the furnace back in. That'd be my first guess.

It's also possible that you need to replace the thermostat, though they don't often go bad. Unless it's a rather complicated system. complete with a heat pump and central air, replacing the thermostat will only involve 4 wires.


You might want to move this thread to the HVAC sub-forum.

mae-ling 01-05-2012 12:57 PM

What is the age of the house?
What type of heating system?

I have a 1973 house with central forced air furnace. The only Cold air return is in the hallway. So unless we leave bedroom doors open the air does not circulate and the bedrooms will be cold.
Also location of ductwork in the system, number of elbows in the line, make a difference. The dining room comes straight off the end. I am told this is bad as it gets the air and then the other vents will not.

jklingel 01-06-2012 02:18 PM

Besides air leaks (which bring in cold air perhaps below the thermostat, delaying the thermo feeling it) sub-standard windows will chill you. You will radiate heat through them, cooling you.

gregzoll 01-06-2012 07:34 PM

My table top at times, will say that it is 66 next to the couch, but the thermostat will read 67.5, or 68.5 if I bump up to 69. I find that ambient temp in various rooms of our house will feel different, due to one reason is the radiating coolness off of the walls, due to no insulation. Now why doesn't the heat crank up and stay on all the time, if I have no insulation in the walls you ask. It is because I went around and did as much air sealing of the outlets, pulled the window trim off and used DAP foam in the can, made sure that the door seals were still in working order around the doors, use door socks also at the doors, or a rolled up beach towel to stop any air leaks from under. I also went through this year and placed 3m Window film over the three worst leaking windows that even though I sealed around the edges, there was still air leakage, due to the fiber gaskets at the top edge between the two sections was still allowing air flow into the area between the double-panes and the storms.

My furnace now cranks up maybe once an hour, and never goes out of first stage, unless it is recovering first thing in the morning from 64 to 68, then it will ramp to 2nd stage, then crank down to 1st stage when it starts to meet the requested temp. You have to really do like I did, and get a table top thermostat with remote sensors, and place them in various rooms, or sections of your main area, and then go from there to see if there are problems with air leaks or insulation, which could have a lot with why you are feeling cooler. That with the humidity level being way too low.

I know that a lot of people are stating that they need to drop their humidity down to 34%, but personally that it too dry. I keep ours around the mid 50's, may get up to 65 for a brief period, but it is a lot more comfortable than drying out the air and having problems getting comfortable during Winter. Same for the Summer/cooling months.

sweaty 01-07-2012 05:30 PM

Especially seal all plumbing and electrical penetrations into the attic and the basement.

mikegp 01-08-2012 06:09 PM

What type of heating system are we talking about? A forced air system will feel warmer while it is blowing and for a while afterward. The temp may stay the same, but the air coming out is warmer than what the tstat will read. I'll feel warmer while its blowing at 55 than while it's off at 60. As time goes on you will lose that effect even if the temp never changes.

Add to that humidity levels, tstat location, drafts, etc.

J187 01-09-2012 10:10 AM

It's a forced air by oil. I got the thermometer/hygrometer and did some experiments. I actually hung the thermometer in the bedroom at the same height the thermostat in the hallway sits. The thermostat read 65 from the heat being off all night. I turned the heat up to 70. An half hour later, the thermostat read 70 and the house felt warm. I checked the thermometer in the bedroom, and it read 69.5. One hour later, the thermostat in the hall still read 69.5, but the house felt very cold. I checked the one in the bedroom - 61 degrees. I picked it up and moved it the dining room across the house - 62 degrees after 20 min. So what I am "feeling" is actually true and very pronounced.

My theory is this - since the middle of the home is and stays warm, but the outer parts get cold fast! The heat does not kick on when it should since the middle of the house stays artificially warm compared to the rest of the house. I have two theories which I will test:

1. There is a lack of insulation and the windows are drafty as someone suggested.

2. The house is a split level. one half of the top floor is over an unheated garage and the other half over a finished basement which IS heated, but gets cold and therefore has a supplemental electric heater. I'm wondering if the bottom floor being too cold is preventing the top floor from retaining heat. This is an interesting thought since the hall w/ the thermostat is directly above the furnace room and the wall the thermostat is on is covering the chimney.

Here's what I will do. I will repeat the same experiment from before, but this time I will heat both rooms of the bottom floor and I will not turn off the electric heaters while I do the experiment. If the rooms upstairs retain heat longer this time, I will have my answer.

gregzoll 01-09-2012 12:20 PM

If the outer wall rooms are getting cooler, then that means you have a lot of air leaks and poor insulation in the house. How much is there up in the attic, and how old is the house?

J187 01-20-2012 02:07 PM

Quote:

Originally Posted by gregzoll (Post 817472)
If the outer wall rooms are getting cooler, then that means you have a lot of air leaks and poor insulation in the house. How much is there up in the attic, and how old is the house?

House was built in 1961. The insulation is good in the walls... its' the first floor that is the issue. The garage is very poorly insulated and the wall between the garage and the other half of the lower floor is virtually not insulated. I'm guessing the insulation between the garage ceiling and bedroom floors is poorly insulated as well.

I ran my experiment. using space heaters, I heated the garage and family room - the lower floor. I got it to about 70 and maintained it down there. I then turned the heat up to 72 upstairs. The hall reached 72 and the perimeter walls were about 71ish. After an hour and a half, the hall was at 71 and the perimeter rooms only dropped to about 69. HUGE difference. My spring project will be tearing the garage apart and properly insulating all around it!

gregzoll 01-20-2012 04:10 PM

j187, get everything together, and with the way the weather is being wacky, you could probably attack it now. If it was me, I would use a dense pack type insulation vs. fiberglass for the common wall, along with sealing any air leaks inside the house with caulk or DAP foam in a can, before putting up the insulation. It would also allow you to put in electric, catv/networking/telco in that area on the living space, if you are needing it, but have not been able to do so, while the garage wall is up. Also, if there is living space above the garage, or a knee wall, make sure that gets insulated also.

Just remember when you put up the new drywall, make sure you get the joints done correctly, so CO does not leak through into the living space. Post pic's once you start, so others can see from your experience, in how they could fix their problem.

biggles 01-20-2012 09:39 PM

realize also that most stats are locatd within sight of the unit return becuase its the return air the stat cycles on not the discharge or rooms.interior walls are a typical mounting spot so they don't have the cold drawing on the room as living rooms bedrooms/over garages.if it isn't mounted around that returm might want to relocate it.if you remove the stat off the subbase see if you have a warm/cold draft out of the hole the wires are coming out of could effect the cycle and or reading

gregzoll 01-20-2012 09:51 PM

biggles, mine is in a great place. It sits on the wall between the hall way entrance from the dining, and the door to our bedroom on the right, just to the left of the stat. Return is on the floor about ten feet from it, other is in the living room as you walk into the front door.

I have found that in my case, this works out great, due to minimal cross breezes from air movement, and pretty much a quiet zone on that wall, if you figure how air would flow through there. Of course, it is also right on top of where the old Octopus sat downstairs, so you could imagine the heat that radiated off of that thing, when it would stay running all the time. Kept the basement nice and toasty during Winter, and warm during the Summer.

SPS-1 01-22-2012 07:13 PM

Quote:

Originally Posted by J187 (Post 817365)
The thermostat read 65 from the heat being off all night. I turned the heat up to 70. An half hour later, the thermostat read 70 and the house felt warm. I checked the thermometer in the bedroom, and it read 69.5. One hour later, the thermostat in the hall still read 69.5, but the house felt very cold. I checked the one in the bedroom - 61 degrees.

So you had the heat off all night and the temperature in the house dropped to 65? And after turned on the heat, it dropped to 61 in one hour? Something very strange here.

If you let your house cool off, you can re-heat the air pretty quickly, but remember that you have thousands of pounds of drywall etc, that have cooled down. All that cold mass is goin to cool off the air pretty quickly, and I would expect the furnace to cycle on again rather quickly. Possibly part of your problem is poor air distribution. Do you have this problem when you maintain your temperature at a warm level? Your thermostat probably has a switch for the fan "auto/on". You might want to switch the gan to "on" for a while after you re-heat your house to keep the air circulating.


All times are GMT -5. The time now is 08:14 AM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved