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We need to measure (at least Ballpark) Delivered BTUH Performance

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anemometer btuh cfm enthalpy chart flowhood performance wet bulb
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udarrell

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Discussion starter · #1 · (Edited)
Great article on page 64 of Contracting Magazine, by Dominick Guarino.
How To Truly Deliver The "Green"

Us he & I, & probably you have often stated; we need to measure (at least Ballpark) Delivered BTUH Performance.

It is actually easy to do & takes only a little time.

It costs very little to buy a good anemometer & figure the CFM, then get an easy fast wet bulb instrument to get Supply & Return wet bulb temps & use the enthalpy chart & simple math, a low cost wet bulb instrument is listed on my Internet pages.

I need a report on how well the WB instrument works.

Though they are great to have, - you don't have to have an Electronic Flowhood in order to ballpark CFM.

Not feeling up to writing more... :pop:- Darrell
 
#2 ·
Our power Company now offers $600.00 for high efficiency heat pump replacements. The rebate requires a Wrightsoft Universal J8 load be emailed to the power company. Then when done, you have to measure air flow using one of 5 different methods, and document it. Then charge must be verified using 1 of 4 different methods, documented. Then all Documents are to be turned over to the power company. The power company will back check a percentage of the installations to make sure no one is cheating. Most companies will be using a magnahelic to check static and check against a blower chart to measure air flow.

Later more testing will be required.

They also offer a loan at 1.25% interest for up to 5 years.

The power company does a free blower door test first to qualify the home.

Long over due.
 
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#3 ·
pretty cool

Kevin O'Neill said:
Our power Company now offers $600.00 for high efficiency heat pump replacements. The rebate requires a Wrightsoft Universal J8 load be emailed to the power company. Then when done, you have to measure air flow using one of 5 different methods, and document it. Then charge must be verified using 1 of 4 different methods, documented. Then all Documents are to be turned over to the power company. The power company will back check a percentage of the installations to make sure no one is cheating. Most companies will be using a magnahelic to check static and check against a blower chart to measure air flow.

Later more testing will be required.

They also offer a loan at 1.25% interest for up to 5 years.

The power company does a free blower door test first to qualify the home.

Long over due.
Click to expand...
 
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#4 ·
udarrell said:
Great article on page 64 of Contracting Magazine, by Dominick Guarino.
How To Truly Deliver The "Green"

Us he & I, & probably you have often stated; we need to measure (at least Ballpark) Delivered BTUH Performance.

It is actually easy to do & takes only a little time.

It costs very little to buy a good anemometer & figure the CFM, then get an easy fast wet bulb instrument to get Supply & Return wet bulb temps & use the enthalpy chart & simple math, a low cost wet bulb instrument is listed on my Internet pages.

I need a report on how well the WB instrument works.

Though they are great to have, - you don't have to have an Electronic Flowhood in order to ballpark CFM.

Not feeling up to writing more... :pop:- Darrell
Click to expand...
Good post, Darrell. One of these days when I get time and sufficient instrumentation and data loggers, I want to document how actual BTU deliverance of a residential a/c system varies with building load and exterior conditions. My own house will serve as guinea pig, as I can more closely monitor the tests. Hopefully this summer I'll get my act together and make this happen.
 
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#5 ·
shophound said:
Good post, Darrell. One of these days when I get time and sufficient instrumentation and data loggers, I want to document how actual BTU deliverance of a residential a/c system varies with building load and exterior conditions. My own house will serve as guinea pig, as I can more closely monitor the tests. Hopefully this summer I'll get my act together and make this happen.
Click to expand...
Thats a lot of sensors.

I'll be waiting for your report/observations.









































Is it done yet? :D
 
#6 ·
We have been measuring equipment performance for several years now, part of utility rebate program on HP's, but never delivered performance. Last year we started to do service agreements, this year a vision of mine came true and we measure equipment performance on each service agreement, as well as figure EER. It takes a little more time but lets the customer know the true health of the system.
 
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Discussion starter · #7 · (Edited)
Test & Fix the Problems to Deliver the Rated Performance

Kevin O'Neill said:
Our power Company now offers $600.00 for high efficiency heat pump replacements. The rebate requires a Wrightsoft Universal J8 load be emailed to the power company.

Then when done, you have to measure air flow using one of 5 different methods, and document it. Then charge must be verified using 1 of 4 different methods, documented.

Then all Documents are to be turned over to the power company. The power company will back check a percentage of the installations to make sure no one is cheating. Most companies will be using a magnahelic to check static and check against a blower chart to measure air flow.

Later more testing will be required.

They also offer a loan at 1.25% interest for up to 5 years.

The power company does a free blower door test first to qualify the home.

Long over due.
Click to expand...
Most companies will be using a magnahelic to check static and check against a blower chart to measure air flow.
Click to expand...
As you & techs here know, static against a blower chart or graph can be way off if the blower wheel blades are filled with lint. The blower wheel will deliver a very low airflow at a low static which on the chart or graph will look like its deliver a lot of CFM.

Also, the blower motor must be performing according to its specifications, bad or wrong rated capacitors, & many the factors can result in a low performing motor. again, it will appear on the chart/graph that it's delivering far more airflow than it is.

That is why even with well sealed ducts, delivered airflow to the rooms ought to be checked, - & then go on to check SA/RA wet bulb use the enthalpy chart to provide them with a delivered ballpark BTUH operating performance.

Even new installs, can often be operating well below their nominal BTUH Rating; that's when you fix the problem causes & deliver the Rated Performance! - Darrell
 
#8 ·
Ballpark performance

I do a lot of light commercial and a quick air balance happens after start-up. I have never checked to see what was the actual delivered btuh performance was. I have 2 start-ups coming up and am now intrigued to see exactly what I am delivering. :D
 
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Discussion starter · #9 · (Edited)
ACFIXR said:
I do a lot of light commercial and a quick air balance happens after start-up. I have never checked to see what was the actual delivered btuh performance was. I have 2 start-ups coming up and am now intrigued to see exactly what I am delivering. :D
Click to expand...
If you go to my web pages I have one low cost way to get a ballpark on delivered operating performance, few ways are going to be dead accurate.

At around a 1000-feet above sea level multiply the CFM by 4.25, that will come closer to the delivered performance. (BTUH=CFM X's 4.5 or 4.25 at 1000-feet X's (SA/RA Wet bulb) X's Enthalpy Change on the Enthalpy Chart.) There are also sea-level increment multipliers that you could use to get a little closer to delivered BTUH.

You'll need the equipments "Expanded Performance Data" so you can compare results to those specific operating conditions.

If your test is not up to the equipments rated performance at those conditions, look for the causes, work on them & you can usually get it there.

Concerning the blower charts & graphs using ESP they are done under laboratory conditions there are a few factors we encounter in the field that can tilt those results; do the actual delivered CFM. - Darrell
 
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udarrell
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