Old Rheem - High Pressure Trips in Cooling When Overnight ODT < Setpoint

[Florida Joy]

No, not Performance or Comfort. Evolution is Bryant's "label" on the Infinity, just not the Infinity Greenspeed with the inverter.

Based on the earlier quote I received on the 3-ton Greenspeed, it may not be as big a difference as you'd think.

Still will have to weigh and decide between high end and 15 SEER models.

Got quotes on the new Bryant Evolution Extreme, which IS the same as Infinity Greenspeed. 3 or 4 ton almost exactly the same price and only about a grand premium over the 2-stage Evolution in the same size.

May still go for the 3.5 ton 15 SEER based on ROI analysis. Also, this contractor's Manual J, which I provided all the data for over the phone, came up with a 44000 BTU cooling load. That's 8000 BTU higher than the lowest of the 3 other Man J's provided by contractors, and about 12000 BTU higher than the Man J that I did online.

Dealer will install a 3 ton if I'm willing to risk it, but ONLY if I agree to a "hold blameless" clause in the contract in case it doesn't hold setpoint in the hot summer months.

Based on avg cooling costs shown on the AHRI site for the models quoted, and the calculations at www.hvacopcost.com, there'd be almost no power cost savings advantage in a 4 ton variable compressor over a 3.5 ton single speed compressor in my house. There's a slight savings advantage in a 3 ton variable speed over a 3.5 ton single speed, maybe $200 a year, at most.

[54regcab]

What is the power cost savings by going to a 3 ton single speed? Even if it didn't hold setpoint during the hottest afternoons, it would quickly catch up after the sun went down. My house is 200sqft smaller than yours but I have 3 more people. Design temps are close, it's 96 for OKC. My 2 ton 14SEER unit keeps it 75 inside on a 100 degree day...

[Florida Joy]

What is the power cost savings by going to a 3 ton single speed? Even if it didn't hold setpoint during the hottest afternoons, it would quickly catch up after the sun went down. My house is 200sqft smaller than yours but I have 3 more people. Design temps are close, it's 96 for OKC. My 2 ton 14SEER unit keeps it 75 inside on a 100 degree day...

The 3 ton single speed 15 SEER might save $100 a year over the 3.5 ton single speed 15 SEER. Too many windows to risk discomfort for such a small return. Catching up after the sun goes down is not good enough, considering I'm home all day long.

[Florida Joy]

There's a slight savings advantage in a 3 ton variable speed over a 3.5 ton single speed, maybe $200 a year, at most.

With that rate of return, it would take 15 years to recover the extra investment for the 3 ton variable speed over the 3.5 ton single speed, providing it lasts that long and maintains the 20 SEER rated efficiency for that length of time.

[tedkidd]

Joy, cycling equipment will cost significantly more than non cycling equipment. Your home is not a laboratory, load changes and cycling depends on how oversized equipment is to load. Balance, noise and comfort are impacted as well. You know this stuff, where's this brainfart coming from? Someone selling fear?

Dave and Jeff live in side by side identical houses. Dave's utility bills are less then half of Jeffs. Jeff has a say at home wife, and 2 kids. Dave has a wife that has a full time job, they have no kids. And they tend to dine out mostly so they aren't home much of the time. How will knowing the utility bills/consumption tell anyone anything about the house itself?

+1, usage habits are a huge factor in bills. Thermostat setpoint is enough to make the records inaccurate.

What about the wife that enters a room and leaves the light on when she leaves, every time.

Define "huge". 10% variation? 50%?

"boy, that's a huge scoop of ice cream". Pan back, and you see a mountain of snow behind you.

"huge" when unmeasured tends to grow to disproportionate levels.

And if it's your neighbor with 8 kids, people intuitively recognize variations in usage and account for them when comparing.

Without having use transparency you don't get to results transparency. And thats a critical quality metric EE really needs for credibility.

[energy star]

Is this a modular home, double wide, or a stick built?