1. ## SEER and HSPF

Here's my understanding of SEER ratings. Lets say you have a 16 SEER Air conditioner for example,that would mean for every Watt of electricity consumed, the equipment would produce 16 BTU's. So to speak if your AC is producing 36,000 Btus and drawing 2250 watts, then your AC must be in the range of a 16 SEER. SEER rating are also figured by testing the equipment in various load conditions (different temperatures inside and outside the house) and then the average of the results is figured in

However what I want to understand is, HSPF. What is HSPF exactly? Heating seasonal performance factor I know but how do they come up with their ratings? like for example, what is the difference in power consumption between a heat pump with a HSPF of 7 and one with a rating of 10. How many more Watts does the 7 HSPF consume and how well does one extract heat from the air better the other? I know at different temperatures this will vary. Someone chime in and help me understand. Give me some equations and explain in a easy to understand manner.

2. HSPF is heating SEER. Averaged over the heating season and reflecting defrosts.

SEER is averaged too and most of the readings are in cool conditions so those in a hot climate should look more at EER which is 95° out and a good load inside.

3. The HSPF even includes heat strips coming into play. But the thing I am wondering is how or what is really the difference in power consumption between a 7 HSPF and a 10 HSPF? like how much more kilowatts are used more than the other over a period of time and if there is a formula out to display this, then what is it?

4. Originally Posted by dgussler
The HSPF even includes heat strips coming into play.
How do they know what size electric heat you are using? I've seen 10 and 15 kw used on say a 2.5T heat pump depending on the cabinet size.

5. Originally Posted by larnot
How do they know what size electric heat you are using? I've seen 10 and 15 kw used on say a 2.5T heat pump depending on the cabinet size.
I have no idea how they calcuate heat strips into the factor lol I have been researching this on the net out of curiosity and cannot find anything that adequately explains HSPF

6. Originally Posted by larnot
How do they know what size electric heat you are using? I've seen 10 and 15 kw used on say a 2.5T heat pump depending on the cabinet size.
Here is where I found the information source on HSPF including heat strips. http://energy.gov/energysaver/articl...rce-heat-pumps .

If you read on down the page you will see their quote "The HSPF rates both the efficiency of the compressor and the electric-resistance elements. The most efficient heat pumps have an HSPF of between 8 and 10."

There are other sources as well that explain that HSPF include the heat strips as a factor in determining overall efficiency of heat pump system

7. Originally Posted by dgussler
The HSPF even includes heat strips coming into play. But the thing I am wondering is how or what is really the difference in power consumption between a 7 HSPF and a 10 HSPF? like how much more kilowatts are used more than the other over a period of time and if there is a formula out to display this, then what is it?
HSPF includes defrost calls. But does not include the KWs or fuel on dual fuels that the aux heat uses. 2 heat pumps can have the same SEER, COP rating but have different HSPF ratings because one uses a time and temp defrost board while the other uses an on demand defrost board.

COP is part of the HSPF calculation.

8. Does anyone know a resourceful website that explains HSPF and COP? Maybe AHRI has one?

9. A diatribe I wrote for a former employer. http://sporlanonline.com/December%20...Cold%20WAR.pdf

10. Originally Posted by Andy Schoen
A diatribe I wrote for a former employer. http://sporlanonline.com/December%20...Cold%20WAR.pdf
You are awesome, Thank you for the link

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I love the title of that, SEER for dummies.

When SEER first was promulgated, thought (and still do) it was a bureaucratic concoction to enable the social control freaks to attach a simplistic (which became administrative nightmare for some) number to hardware vs. plain old COP and conditions.

Still prefer to use COP and operating conditions.

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