Please give me the likely sources of this information.

More like 75F/63F.

Unless you have a perfectly sealed house, controlled fresh air requires pressurization. A 3 ton, 2 stage unit delivers 26K sensible, 31K total. ), exhaust/negative p is a good thing, no? You simply order more and more triple scoop cones, always being sure to give one scoop to the dog from each cone, and continue until your weight is under control.

Condensate Flow (kg/hour) Pressure loss. Our Manual Js are around 1300-1500 sf/ton, but when it gets to the Manual S, the high efficient equipment becomes 800-1000 sf/ton; not the 10-15% oversize per code. I hate new build. I've written about this before.

The problem we are seeing now is we are finding, at least in retrofit, we do NOT want balanced ventilation for IAQ control. It's easy to get whatever load you want when you do a Manual J load calculation. Thanks, Kellie! Design your condenser to be twice as large as you can imagine it needing it to be, then make it 50% larger than that.

Probably due to spa's/pool's/etc. Look at the square feet per ton number you get to see if you're in the ballpark.

For this reason, there is correctly set out by manufacturers who set their standards by efficiency estimates that assume your HVAC system will be connected to a duct syst… : Cooling capacity required in kW = Total area to be air-conditioned [m2] ÷ 5, *to convert to Btu/hr, multiply the kW result by 3412 * to convert from ft2 to m2, multiply the area in ft2 by 0.093, Double volume (i.e. Real-world case studies are provided. east-west direction), Additional heat sources such as bar fridges.

I guess homeowners need to accept less interior square footage and architects need to place the mechanicals in a well-insulated (for sound) room that's large enough to accommodate the system.

We don't collect information from our users. Reid, I agree with Allison when he suggests an ERV is not a dehumidifier. I live near Indianapolis and I track the weather for some training sessions I present. Thanks for helping us keep our "cool" with our clients. ENERGY STAR Version 2 doesn't require much in the way of checking Manual … So if i understand you correctly infiltration is one of the values that gets guessed at with manual J. Yep. A rigged system... it sSeems like no-win even if we try our best to do the right thing. Please let us know here why this post is inappropriate. In our environment of upper 70s wetbulb temps / mid 70s dew points, it is better to walk / run away from projects demanding oversized equipment in leaky buildings rather than "own" the inevitable discomfort and elevated mold risk. If the builder has had blower door tests done before and has a record, you can use that. Air Conditioning Calculations - Rule Of Thumb. double ceiling height), A large window area (e.g. To the extent that IAQ issues are internally generated (odor, moisture, pet dander, dust, smoke, cooking, voc's, etc. Contractors who use whole-house rules of thumb often don't get the right amount of conditioned air for individual rooms.

(I need to look that up) In other words, if the equipment is rated 2.25 tons sensible and 3.0 tons total (standard 75% sensible heat ratio), but the load is, for example, 2.5 tons sensible 2.8 tons total (90 % SHR) you'll be OK - the SHR can be increased at a slight reduction in total capacity. Generally, control-valve bodies are one size less than the line size.

DEAR CRG:  THANK YOU FOR YOUR RESPONSE. 2. http://www.heatload.com/unico/special.html, http://www.warmair.net/html/window_air_cond.htm, http://www.voltasac.com/split_ac_home.htm, eBook - The Future of Product Development is Here, Solutions Brief - Protecting and Rescuing On-Ground Personnel, White Paper - Cobots vs Covid: Today's Manufacturing Reality and Tomorrow's New Normal, Datasheet - Creo Generative Topology Optimization Extension. For typical homes in most of the country, 1.5-2 tons is not grossly oversized. Our sensible loads are getting too low to depend on the air conditioner to do it all. Work with client to seek and destroy those two tenths (or more)...find some low hanging fruit such as air infiltration tightening, extra attic insulation, duct sealing, internal gain reduction, window solar filming / screening. Ted wrote: "science project"... "perfection can become the enemy of great"... Not even close. If it is a cookie cutter house, than they usually just pic an average design and apply it to all houses. Since most homeowners can't completely gut and abate their homes, our approach has been to design solutions that fit client problems and budget. And so, mechanics developed the "rule of thumb" that .22uF condensers are the size to use if you don’t know the value of the original condensers. A rigged system... it sSeems like no-win even if we try our best to do the right thing.".

I wasn't suggesting that it would replace the AC, but rather that it replaces the conventional ventilation system. It’s a goal shared by embedded computing manufacturers like Abaco: we never forget who we serve.This case study describes how a major international contractor integrated an Abaco single board computer at the heart of its CAS/CSAR solution.