Page 16 of 17 FirstFirst ... 691011121314151617 LastLast
Results 196 to 208 of 211
  1. #196
    Join Date
    Nov 2004
    Location
    SW FL
    Posts
    6,238
    Quote Originally Posted by energy star View Post
    In Home now: 10 SEER 3.5T 2400 CH @ .15KW =1512
    Wants: 20i 17.5 SEER (actual seer on this unit, 17.75 17.5) 4.0 T 2400 CH @ .15KW = 980

    May save 450-550 a year
    FPL= $0.105 / kW-Hr
    $ 1512 * .105/.15 = $1058
    $980 * .105 /.15 =__ $686
    _________________ $372 which is in mid-range of $340 - $420
    Designer Dan
    It's Not Rocket Science, But It is SCIENCE with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE

    Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities

  2. #197
    Join Date
    Aug 2012
    Location
    Florida Space Coast
    Posts
    503
    [QUOTE=dan sw fl;14037671]
    Quote Originally Posted by Florida Joy View Post

    $1,200 * 0.7 = $840 A/C ... = $140/ month
    __________ .. $360 Normal use = $60/ month

    40% - 50% = $340 to $420.
    I had hopes of having an extra hundred dollar bill for my piggy bank in each of the summer months, based on "purported" savings that one of my Trane estimaters claims the folks 2 doors down are getting since he installed a 15 SEER in that house. They're renters and I don't know them, so I'm a little shy to knock on the door to confirm what he said.

    Oh well, give me at least half that in savings and a reasonably priced system built to last 20 years or more and I'll be happy. HA, HA, I know that's asking a lot!

  3. #198
    Join Date
    Jul 2007
    Location
    Delaware
    Posts
    3,824
    .105? I used a larger number, gotta link to .105
    Always here

  4. #199
    Join Date
    Jan 2009
    Location
    Keokuk, IA
    Posts
    5,520
    Quote Originally Posted by dan sw fl View Post
    Definitely a FALSE PREMISE in This Situation:

    It's impossible to improve upon 40% Relative Humidity.!.!!..!!!
    Sure you can in 2 ways. 1) 40% RH @ 75F is great, 33%RH @ 77F is even better in terms of energy savings but is equally comfortable. 2) if hte sytme cna reach 40% RH sooner, then more capacity will go into sensible cooling than latent. A smaller coil with the same load, will drain sooner and more water than a larger one.

    Right now my house is at 43%RH @ 74F upstairs and 33%RH $77F downstairs. Both are comfortable, but downstairs has lower proportional heat loss. Which is good since it's 10 SEER and oversized.

  5. #200
    Join Date
    Aug 2012
    Location
    Florida Space Coast
    Posts
    503
    Quote Originally Posted by motoguy128 View Post
    Right now my house is at 43%RH @ 74F upstairs and 33%RH $77F downstairs. Both are comfortable, but downstairs has lower proportional heat loss. Which is good since it's 10 SEER and oversized.
    You're in Iowa? How far is that from the Atlantic Ocean and what's the average RH and dew point outside your house in June, July and August? In my neighborhood the average RH is 90% with an 80 degree dew point and average temp of 88-90.

    My 12 year old, falling apart Rheem maintains inside RH at 40%, but I haven't seen any new equipment that claims to be able to match or beat that.

  6. #201
    Join Date
    Nov 2004
    Location
    SW FL
    Posts
    6,238
    Quote Originally Posted by energy star View Post
    .105? I used a larger number, gotta link to .105
    Yes, stop by & I'll show you my FPL electric bill.

    Or see post # 188 for kw & $. = $00.105 kW/hr
    Designer Dan
    It's Not Rocket Science, But It is SCIENCE with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE

    Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities

  7. #202
    Join Date
    Nov 2004
    Location
    SW FL
    Posts
    6,238
    double - erratic PC.
    Designer Dan
    It's Not Rocket Science, But It is SCIENCE with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE

    Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities

  8. #203
    Join Date
    Nov 2004
    Location
    SW FL
    Posts
    6,238
    Quote Originally Posted by motoguy128 View Post
    Right now my house is at 43%RH @ 74F upstairs and 33%RH $77F downstairs. .
    77'F @33% R.H.

    How do you get L.A.T. < 47'F?
    _ When is the last time your hygrometer was calibrated?

    http://www.thermalinc.com/math/wetbulbcalc.htm
    Designer Dan
    It's Not Rocket Science, But It is SCIENCE with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE

    Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities

  9. #204
    Join Date
    Aug 2012
    Location
    Florida Space Coast
    Posts
    503
    Quote Originally Posted by energy star View Post
    .105? I used a larger number, gotta link to .105
    This is the info directly from my August FPL bill:

    kWh used 2360
    Customer charge: $5.90 per month
    Storm charge 2.78
    Gross receipts tax 6.08
    Franchise charge 14.59
    **The electric service amount
    includes the following charges:
    Fuel: $92.49
    (First 1000 kWh at $0.033430)
    (Over 1000 kWh at $0.043430)
    Non-fuel: $135.94
    (First 1000 kWh at $0.051840)
    (Over 1000 kWh at $0.061840)

  10. #205
    Join Date
    Jan 2004
    Location
    Lancaster PA
    Posts
    67,721
    Quote Originally Posted by Florida Joy View Post
    You're in Iowa? How far is that from the Atlantic Ocean and what's the average RH and dew point outside your house in June, July and August? In my neighborhood the average RH is 90% with an 80 degree dew point and average temp of 88-90.

    My 12 year old, falling apart Rheem maintains inside RH at 40%, but I haven't seen any new equipment that claims to be able to match or beat that.
    90F drybulb with a dew point of 80F is less then 73%RH.
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

  11. #206
    Join Date
    Nov 2004
    Location
    SW FL
    Posts
    6,238
    Central and South FL is typically > 90% R.H. from 3 AM to about 9 AM.

    90% R.H. ..=.. Dew Point is 2'F less than Dry Bulb.

    Obviously, opening windows in early morning is NOT an Optimum cooling option for nearly 5 months.
    Designer Dan
    It's Not Rocket Science, But It is SCIENCE with "Some Art". ___ ___ K EEP I T S IMPLE & S INCERE

    Define the Building Envelope and Perform a Detailed Load Calc: It's ALL About Windows and Make-up Air Requirements. Know Your Equipment Capabilities

  12. #207
    Join Date
    Jan 2009
    Location
    Keokuk, IA
    Posts
    5,520
    Quote Originally Posted by dan sw fl View Post
    77'F @33% R.H.

    How do you get L.A.T. < 47'F?
    _ When is the last time your hygrometer was calibrated?

    http://www.thermalinc.com/math/wetbulbcalc.htm
    The humidity sensor in my thermostat agrees. Based on comfort, I also agree. If the humidity were higher, 77F would feel too warm.

    THe supply temp isn't 47. I haven't checked it recently, but it's probably in the low 50's. I run the airflow a little low and the ductwork is close to sweating with a dewpoint around 50F in the basement. Airflow is probably around 1200CFM on a 3.5 ton system, so around 350CFM/ton. When I use DoD, that drops about another 100CFM. So about But it does have a TXV and I believe part of the coil surface is getting that cool. Further, the supply temp on my upstairs Infinity probably is under 50F. With revserse stack effect, the upstairs does most of the dehumidification.

  13. #208
    Join Date
    Aug 2012
    Location
    Florida Space Coast
    Posts
    503
    Quote Originally Posted by motoguy128 View Post
    Sure you can in 2 ways. 1) 40% RH @ 75F is great, 33%RH @ 77F is even better in terms of energy savings but is equally comfortable. 2) if hte sytme cna reach 40% RH sooner, then more capacity will go into sensible cooling than latent. A smaller coil with the same load, will drain sooner and more water than a larger one.

    Right now my house is at 43%RH @ 74F upstairs and 33%RH $77F downstairs. Both are comfortable, but downstairs has lower proportional heat loss. Which is good since it's 10 SEER and oversized.
    Quote Originally Posted by Florida Joy View Post
    You're in Iowa? How far is that from the Atlantic Ocean and what's the average RH and dew point outside your house in June, July and August? In my neighborhood the average RH is 90% with an 80 degree dew point and average temp of 88-90.

    My 12 year old, falling apart Rheem maintains inside RH at 40%, but I haven't seen any new equipment that claims to be able to match or beat that.
    Just for kicks, I looked at the forecast for today's weather in Des Moines, Iowa. The outside RH today will range from a low of 25% to a high of 41%. Compare that to the outside RH for today at my place in Florida.... between 75% and 85%.

    It sounds like opening the windows in Iowa would do as well as A/C in maintaining comfort... and with fresher air!

Page 16 of 17 FirstFirst ... 691011121314151617 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event