joepa
join:2000-08-02
Allen, TX
clubs:
| reply to dwhitener
Re: 3 year old house will not stay cool
Sounds exactly like my house here in Allen, TX. I really think my problem is a combination of issues. It is poor ventilation in the attic (soffit vents blocked by insulation, not enough of them) and some insulation problems with all the knee walls in my attic.
I am calling them knee walls but they are really the parts of the walls that stick up above the rest of the attic floor. My bedrooms and gameroom have higher ceilings than the foyer and hallway. These higher ceiling extend further into the attic. They are insulated but not that well.
I would double check that you have good ventilation in the attic before going for the radiant barrier. By the way there was a great article in the Dallas Morning News a few months back on radiant barriers.
»www.dallasnews.com/sharedcontent···bd0.html
Joe |
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dwhitener
@verizon.net
| reply to scooper
I'm not sure what the R rating is. I have a lot of windows facing west on the front of the house. I had them tinted, which helped some. I believe that insulating more and radiant barrier would help. The only other alternative is to put an auxiliary unit in to run only when we have these super hot days. I don't want to over size my central unit and cause moisture problems. |
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nocannothave
join:2006-10-14
Kennewick, WA
 ·Charter Pipeline
 ·Verizon Online DSL
| reply to scooper
In the summer we routinely reach 100+ with very low humidity. On these days, I set the thermostat to 66 at about 10am. It reaches this temp (and will sometimes shut off for a bit) and steadily climbs as the day wears on. By the time outside is 102, inside is now at 72 or 73.
The A/C unit runs pretty much from 8 am until about 1 am on the hottest days. At this point, I don't even care.
1800 sf
vaulted main room facing north with windows on the west - 13'6" height
8 ft ceilings in the rest of the house
Blown in insulation in above the ceiling. Not sure how deep.
My office is always a couple degrees warmer (2 computers), and that annoys me. I'd like to make the office cooler, but it's ok most days.
Try a cooler setting (than you would prefer) on the thermostat earlier in the day. The idea is to get a jump on the heat. It works for me. |
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scooper
join:2000-07-11
Youngsville, NC | reply to dwhitener
Radiant barrier isn't a bad idea - what's your ceiling R factor ? It should be at least R35 - and R50 wouldn't be out of line. |
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dwhitener
@verizon.net
| reply to TooHotToday
I live in North Dallas and have the same problem. AC is fine until the outside temp gets above 95 deg. I keep the thermostat set on 76 and that is where it stays until about 3PM on a 100+ day then it will climb to 79 or 80 and stay there until around 9PM than it starts falling back to 76. I have had the AC unit checked and serviced and was assured that it was sized properly for my square footage. I am considering adding more insulation and having a radiant barrier installed on the underside of my roof. Some summers we have 40-50 days of 100+ temperatures and although 80 feels pretty good when it is over a hundred outside, I still want my system to keep the temperature where I set it. |
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cowboyro
join:2000-10-11
Shelton, CT
 ·AT&T U-Verse
·Comcast
 ·Optimum Voice
1 edit | reply to TooHotToday
2.5 or even 3 ton is undersized for such a big house. I had a CA system installed last year, calculations done by me with the help of various websites and the ones done by few contractors yielded 4.5ton for my 2300sqft colonial. I figure that the OP has a ranch style house, therefore more roof surface - and more heat coming in. I have a 2.5 ton unit servicing the 1400sqft of the lower level and a 2 ton unit servicing the 900sqft of the upper level...
Edit: the system handled cooling very well last year, was able to keep up with heating up to 25F during winter while maintaining 70F inside. |
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aeblank
join:2004-09-07
Cadillac, MI
| reply to Sly
said by Sly  :Yea, me neither. What you described is a ground source heat pump with a desuperheater option. They do exist but are very expensive to install... I have access to a back hoe, I can run the ground loops. I plumbed my entire furnace setup, so I can tie in the desuperheater. I just need to find a kickass hvac guy to work with me on this. That's all. =) |
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joetaxpayer
I'M Here Till Thursday
join:2001-09-07
Sudbury, MA
·Comcast
·Comcast Formerly ..
| reply to TooHotToday
I've been following this, and understand there are potential multiple issues involved. Have you checked Attic temp? If attic is not well insulated from second floor ceiling, and circulation is bad, you can have a temp 20 degrees hotter than outside. Still a builder issue, but not the HVAC guy. And a different path to address (insulation and vent fan VS the AC system). This doesn't take much effort to check. |
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Sly
Premium
join:2004-02-20
Johnson City, TN
clubs:
·Packet8
·Callcentric
·Comcast Formerly ..
| reply to aeblank
Yea, me neither. What you described is a ground source heat pump with a desuperheater option. They do exist but are very expensive to install...
--
"The penalty good men pay for indifference to public affairs is to be ruled by evil men."
- Plato - |
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aeblank
join:2004-09-07
Cadillac, MI
| reply to Sly
From what I can see, it's really just a heat exchanger, a circulator, and some controls. The controls maintain a hot water temp in the useful range (120+) by varying the flow through the exchanger.
A perfect system would be a heat pump (that dumps its heat into the ground--therefore very efficent) but with a desuperheater inline before the ground loop to create some hot water for free (less purchase price and electricity).
I've never understood dumping the heat into the air. The air is 100 and the ground is 50. Not to mention fan noise. |
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scooper
join:2000-07-11
Youngsville, NC
| reply to linicx
said by linicx :Might be hunky dory in NC, but a heat pump is not worth much when it is 40 below in Chicago. Works fine as an Air Conditioner, not so well as HEAT SOURCE below about 20F. That's why they have the auxilary heat strips or you put in a furnace. But your whole initial comment was that they don't work as air conditioners - which I am roundly refuting. |
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linicx
Caveat Emptor
Premium
join:2002-12-03
United State | reply to scooper
Might be hunky dory in NC, but a heat pump is not worth much when it is 40 below in Chicago.
--
Mac: No windows, No Gates, Apple inside |
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Jetflier
@teksavvy.com
| reply to TooHotToday
Hi,
Sorry to hear about your problem.
There are two things that you need to check. First, what is the temperature coming out of the air vents or diffusers? If the outside temperature is 100 F, then the air coming out of the vents should still be at least 65-70 F. My a/c, at 90 F outside temperature, blows about 55 F air from the air vents.
Second thing you need to check is that the blower motor is operating at high speed. How much air is coming out of the air vents? The motor wiring could be set wrong and you do not get enough cold air to various rooms in the house. Also, the motor bearings could be bad causing the motor speed to drop. The cooling coil could be blocked by dust or maybe it is icing up preventing proper air circulation. So, those two main things you need to investigate: is the air out of the vents cold enough and are there enough air flow out of the vents.
Once you get your a/c fixed, I highly recommend that you purchase an anemometer that measures air speed, air flow, temperature, etc. You use this device to take measurements at air vents throughout the house as reference values. Then if you ever have any further problems with your a/c, you can eliminate many possibilities before calling a technician. These units can be purchased cheaply from ebay starting at $25 and up. This is much cheaper than having a service person to come in and notice something simple as dirty filters and charging you $100 for a visit. Good luck. |
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rob_in_chatt
Premium
join:2004-09-17
Chattanooga, TN | reply to TooHotToday
according to google, this is a 3 ton AC unit with a 70000 btu heat pump. |
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IcePirate123
join:2003-01-12
Columbus, OH
| reply to TooHotToday
Quite simply, when the original installer comes out, kick it up a notch. Tell him that you believe there is a problem with your air conditioner and it has been there since day one. Tell him that if the air conditioner will not maintain the house at 70 degrees regardless of outside temperature you are going to call a seperate air conditioning company for an inspection of the unit and bid to properly repair. You will then submit this bid to the original builder of the house and if they do not wish to pay it your lawyer. If you have to actually get a bid and send to the original builder and they decide to try to fight you, tell them you are going to call the local permit department and have your house inspected. If as I suspect this house was built on the minimum amount of permits and lowest bidders, it will be much cheaper for them to repair or even replace your whole air conditioning system than have any other projects STOPPED by the permit dept for a inspection compaint. |
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TooHotToday
@sbcglobal.net
| reply to TooHotToday
Hi...OP here again!
Sorry I am not much of a help because I am very new to this whole thing and do not know much of the technicalities.
1st- the house is a one story with high ceilings, no skylights and all windows are covered with wooden blinds. I don't think there are any venttilation systems in the attic.
2nd- Unit has not been working properly until now, Didnt work the first summer we lived here and this summer we had a tech out and he told us that the unit in the attic was mismatched to the unit outside. This is when we contacted the builder and then the installer and they installed a new unit in the attic to match the one outside. Works ok when it isnt very hot, but when temps get to 100+ it really struggles.
3rd- I set the AC to 75 today and it held that temp until about 3pm, then it slowly got up to 82 degrees.
4th- Original installer is coming out again this week to take a look, but he says that a 20 degree difference is acceptable...I know some other people on here also said that, but, that makes no sense to me. That is telling me the best you can expect in 100 degree weather is 80??? I know a lot of people keep between 72-75 around here.
If more info is needed, let me know and I will repost.
Thanks again for everyones help! It is much appreciated! |
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RR Conductor
RailRoadDude
Premium
join:2002-04-02
Redwood Valley, CA
·Comcast
2 edits | reply to TooHotToday
I see some advice about dehumidifiers, humidity really isn't a problem in NorCal during the heat of the day. Here where I live in NorCal (inland Mendocino County, Northwestern CA) the humidity gets in the 20-30% range during the day, but goes back up to around 70-80% at night with the cooling, onshore (we're 28 miles from the coast here in Redwood Valley) flow in the evening. So here at least, hot=low humidity, cool=high humidiity.
Edit-Here, the inside of the house can get very dry, humdifiers are a good thing to have to help put more moisture in the house. I've been in the south and east, you guys can have that sauna stuff, no offense  
--
You've got to stand for something, or you'll fall for anything. |
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burner50
Pinlifter
Premium,VIP
join:2002-06-05
EN22wm
·Mediacom
·FrontierNet Intern..
| reply to Sly
said by Sly :Please do not do this. Spraying the condenser does work... but as the sprayed on water evaporates, it leaves behind calcium and mineral deposits on the coils. These build up on the condenser and act as an insulator which severely reduces the unit's efficiency. Then as the condenser can't remove enough heat, the head pressure rises in the compressor which makes it run hotter. Then your compressor fails... If you want to cool the condenser, then look for a unit called a desuperheater. This is a heat exchanger which hooks up to the condenser side and circulates cold water through it and then runs it to a water heater tank for pre-heat water. A desuperheater cools down the condenser which makes the heat pump run more efficiently and it uses that heat to heat your home's water... making your water heater more efficient as well. Repeat... do NOT simply spray water onto the condenser. possible to use distilled or rinse with distilled water...
I used to do this in the radiator of a racecar to cool it down faster for work in the pits. Spray whatever water I could find out of a pressurized cylinder, then rinse with distilled in a garden sprayer.
--
I'm tired of killing stupid people just trying to do my job and go home! |
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KrK
Heavy Artillery For The Little Guy
Premium
join:2000-01-17
Tulsa, OK
·AT&T Yahoo
·AT&T DSL Service
·Cox HSI
·AT&T Southwest
| reply to Sly
Why is the first I've heard of these.... These clearly are a great way to make homes more energy efficient---- they hit the two biggest energy expenses in a home--- A/C and Hot water generation (well, not counting winter heating I guess.)
Real boon in the summer.
--
"Fascism should more properly be called corporatism because it is the merger of state and corporate power." -- Benito Mussolini
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Sly
Premium
join:2004-02-20
Johnson City, TN
clubs:
·Packet8
·Callcentric
·Comcast Formerly ..
2 edits | reply to KrK
said by KrK :That Turbotec Envior-Pak unit looks like quite the ticket! Talk about win/win.... saves on air conditioning costs AND hot water expense. Wow... It's only a matter of time before this market takes off. Found another desuperheater...
»www.doucetteindustries.com/produ···_res.htm |
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