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Type: Posts; User: tab-tech

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1. Thread: How Is Duct Air Volume Calculated From Air Velocity Measurements?

by tab-tech
Replies
48
Views
6,568

When using Static Pressure as the target...

When using Static Pressure as the target measurement for desired volume the formula becomes SP2 = SP1 x (CFM2/CFM1) squared
2. Thread: How Is Duct Air Volume Calculated From Air Velocity Measurements?

by tab-tech
Replies
48
Views
6,568

A calibrated capture hood is the easiest and most...

A calibrated capture hood is the easiest and most convienient method of measurement since you don't need to use a "correction factor" for the Ak (free area factor) which would be required using a...

by tab-tech
Replies
10
Views
7,095

In keeping with the general "rule of thumb" that...

In keeping with the general "rule of thumb" that 400 - 500 cfm expected per ton of cooling then, 430 cfm return would be low, or about 21% of the estimated 2,000 total cfm for a 5 ton unit (unless...

by tab-tech
Replies
10
Views
7,095

Depends on if the unit is single fan or dual fan....

Depends on if the unit is single fan or dual fan. (supply fan only or supply and return fans)
Also, if dual fan, what minimum OA and minimum EA design is at full mechanical cooling.
If single fan,...
5. Thread: K Factor for Trane VAV

by tab-tech
Replies
15
Views
9,706

For TRANE VAV's, the K-Factors is actually the...

For TRANE VAV's, the K-Factors is actually the volume in CFM that the box should deliver at 1.00 inch of pressure drop.
How-ever, these are based on ideal installed conditions which are not always...

by tab-tech
Replies
10
Views
1,904

say it isn't so.....

I had a rank odor coming through my house duct system.
Traced it out and found a dead. half-rotten rat in the main duct.
The smell would knock a dog off a gut-wagon.

by tab-tech
Replies
45
Views
2,769

I play guitar as a hobby...

TAB = Testing, Adjusting and Balancing
(never thought about TAB = music tabulation) good one tho!

by tab-tech
Replies
45
Views
2,769

Check this one out...awesome!!

Check out this one and reply what cha think.

9. Thread: Dirty filters and blower amps.

by tab-tech
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22
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2,283

you are right...for the most part

For the most part, adding restriction to the available air flow will also lower the current draw. This also depends on what TYPE of fan wheel you have.
If "Vaneaxial fans" are used, adding...

by tab-tech
Replies
15
Views
1,376

CV value of valves

CV values of valves are also typically based on straight water without any additives such as glycol or rust inhibitors, etc.
If additives are used then there is a correction factor required.
If you...

by tab-tech
Replies
15
Views
1,376

CV value of valves

The CV value of valves are typically the volume of water in (GPM) the valve will provide at a 1.0 psi drop at full open.

by tab-tech
Replies
15
Views
1,376

Try burping the system.

Have you checked the possibility of an air bound coil?
Air becoming trapped at coil high points can cause water flow to be sluggish.
Try venting the system at high points until you burp it.

by tab-tech
Replies
2
Views
660

You could put electric strip heat in the ducts but you would have to add in the electrical cost of running the fan. They work like toasters.
Electric heat is 100% efficient. Only trouble with that...

by tab-tech
Replies
20
Views
2,609

I/R good for Delta T measurement

I/R readings are best I find for verifying temperature differentials.
Even if the actual temperatures tested are "off"...they will be "off" by the same amount of error giving you a good indication...
15. Thread: Economizing with outside air

by tab-tech
Replies
97
Views
9,225

Thats what I'd call.....

...dryer than a Popcorn Fart.
16. Thread: Economizing with outside air

by tab-tech
Replies
97
Views
9,225

I live in Maine where economizer cooling...

... is the cats meow. I've seen conditions in early mornings where OSA temps are 55 - 60 degrees with RH levels at 90% or higher. (dense fog from dew lifting off the ground and surface water...
17. Thread: K Factor for Trane VAV

by tab-tech
Replies
15
Views
9,706

Sometimes K factors are....

....the amount of CFM a box will deliver at 1 inch of differentialpressure.

by tab-tech
Replies
18
Views
2,031

TOUCHE'..........

by tab-tech
Replies
8
Views
863

Iraqi freedom will not give way to the tyranny that once ruled, for they have now tasted the sweetness of freedom.
Its like their country has just put on a new pair of shoes.... they are gonna have...
20. Thread: Glycol use in chill water loop

by tab-tech
Replies
12
Views
2,043

You are still basing your mixture on a percent of gallons in the system.....

.....you are just simply using temperature/color shade as the medium of determination.
21. Thread: Evolution is *not* a theory

by tab-tech
Replies
1,030
Views
44,043

Get a grip believers.....

ScrogDog doesn't care what anyone else thinks...he's just trying to beat the 9mm thread.
Winds up... he's beating a dead horse.
As Bootlen stated way back at the beginning of this topic...

...
22. Thread: return-air opening wider than supply air, roof top unit???

by tab-tech
Replies
16
Views
2,314

Since all fans (and pumps for that matter).....

....work on a differential pressure based curve...I'm thinking that outside air intake ducting will typically offer less resistence then it's return air ducting. There-fore, to move the same amount...
23. Thread: Glycol use in chill water loop

by tab-tech
Replies
12
Views
2,043

....that capacity loss will always be found when using glycol in a system.
The loss when the mixture is above 30 - 40 % is greatly increased.
Good ol' plain water (no additives like floride,...
24. Thread: Identity theft....a growing concern.

by tab-tech
Replies
17
Views
1,285

Ahhh for the good 'ol days.....

....when a persons' word was as good as gold.
Sorry to hear about you and your Dad...the stuff in between us would bother me more than the incident itself.
Sometimes we must learn not only by our...
25. Thread: Identity theft....a growing concern.

by tab-tech
Replies
17
Views
1,285

A new WalMart just opened up here.....

....and they have several "self-checkout lanes for your convenience" much the same as described by Bootlen / Blockbuster senerio.

I think "convenience' here means at the collection of payment...
26. Thread: Identity theft....a growing concern.

by tab-tech
Replies
17
Views
1,285

I'm seeing alot of news about the growing...

I'm seeing alot of news about the growing concerns of identity theft.
Any comments, suggestions on this subject?
Should a more secure and reliable identification verification be considered to the...

by tab-tech
Replies
33
Views
2,571

Can you be sure.........

they were ALL girls?......

by tab-tech
Replies
34
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1,976

When anews report becomes a news "STORY" ...

... we might as well read the bottom of tequilla bottle.

These folks can help at least get the message out of how most Americans feel about the Main Stream Press.

American Family Association...
29. Thread: Certified Balancer seeking temporary relocation / work

by tab-tech
Replies
0
Views
778

20 years experience; industrial/commercial/light...

20 years experience; industrial/commercial/light commercial projects; have own equipment and transportation; looking for temporary balancing work and willing to relocate for a couple months....

by tab-tech
Replies
6
Views
1,348

An accurately and adequately operating control system.....

....will not work well under extreme load conditions unless it has been accurately and adequately balanced. Comfort levels may or may not be adversely affected under light load conditions. This is...
31. Thread: fan powered vav boxes

by tab-tech
Replies
20
Views
8,310

If primary air goes to Zero......

....by sequencing the variable damper to full closed, how does the occupied spaces satisfy minimumoutside air requirements?
Just curious....

by tab-tech
Replies
85
Views
5,233

..... the duckbill platypus in the evolution process.
(I ain't buying that a duck mated with a beaver)

by tab-tech
Replies
85
Views
5,233

Ever heard of steroids? .... lol

by tab-tech
Replies
85
Views
5,233

Evolutionist S. Lovtrup:

Micromutations do occur, but the theory that these alone can account for evolutionary change is either falsified, or else it is an unfalsifiable, hence metaphysical...

by tab-tech
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85
Views
5,233

This guy studied it for 20 years.... ask him -

Dr. Colin Patterson, Senior Paleontologist, British Museum of Natural History, London. The following quote was taken from a speech given by Dr. Patterson:

Last year I had a sudden realization for...
36. Thread: A SPECIAL Thanksgiving messsage to all you "separation of church and state" idiots

by tab-tech
Replies
28
Views
1,880

Here's a link to an informative site........

...... let me know what you think.

http://www.godsaidmansaid.com/topic3.asp?Cat2=244&ItemId=794

Is America a Christian Nation? (part 1)...
37. Thread: Snow Prevention in Outside Air Intakes

by tab-tech
Replies
3
Views
1,224

A popular louver here in Maine.....

.... is called a "hurricane louver." I think what you want is something that offers the total air mass flow you require at a low inlet velocity to keep from drawing the snow in with fresh air.
I've...
38. Thread: how is work out there?

by tab-tech
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18
Views
2,177

My bid search engine sez.........

.....there's over 6,500 construction jobs bidding in Texas right now worth 2.2 billion.
(just remember to tip yer hat to the ladies while your there)
39. Thread: Give Kerry Some Credit

by tab-tech
Replies
9
Views
884

I think the cost of.......

..... keeping all those high price lawyers on board the Kerry Team may have had alot to do with a waste of time and money to convince Kerry to concede, Edwards wanted him to drag it out.
Kerry may...
40. Thread: HVAC Talk Presidential Vote

by tab-tech
Replies
43
Views
3,428

George W. Bush.....................

...... he's not perfect but Kerry stands sooo faaar tooo the leeeft---- he doesn't know whats right.
41. Thread: Republicans don't play fair

by tab-tech
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35
Views
2,348

Take a sign.......

..... set it up in your back 40 and blast it a few times with a shot gun. #4 bird shot works good.
Take the sign back to its original place in town and watch the fun begin.
They'll have fun diggin'...

by tab-tech
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11
Views
1,072

Although this is not a "physical" boxing match....

....any "true defender" knows that you save the KO upper cut for the last round.
The bit where Bush made his point regardless of what the mediator wanted was classic too. When someone stomps on your...
43. Thread: WHY I AM A DEMOCRAT

by tab-tech
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20
Views
1,576

Another liberal panic twist.................

....... it was just an apple. Now go change your pants.
44. Thread: Republicans don't play fair

by tab-tech
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35
Views
2,348

yeah.................

....isn't just like a worried Dem? Just like Kerry not having a game plan for his platform on how HE would handle the war on terror and blaming Bush for it. What a sissy.
Hey....I've got an idea...

by tab-tech
Replies
34
Views
2,414

Decent post WM...............

........ VA hospitals are where many heros can be found also.
There demeanor, the same- happy to be alive still and just as happy to be living in a country where freedom is as important as life...

by tab-tech
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26
Views
2,063

Re: Re: Kerry has proven....

I'd laugh in your face if you were standing here, but I'll just save the laughter collectively for Nov. 3rd. The smell of victory will be sweet compared to the same 'ol crap you dish out. Doom and...
47. Thread: The shrub - what a loser!

by tab-tech
Replies
13
Views
1,306

They don't poll the silent majority........

......... and the main stream media loves to dramatize everything and spin it to their own twist.
I think most folks, who don't get calls from pollers, can see right through the fog of politics and...

by tab-tech
Replies
7
Views
905

My youngest grandson....

was born 3 months premature. Had to give him steroids to get his lungs developed.
2 and a half years later, he's now a big boy at about 35-40 pounds and the imput drive this kid has for life is...

by tab-tech
Replies
26
Views
2,063

Kerry has proven....

...... that his self- confidence level is weak- thus the need to change stances when-ever the wind changes.
I wonder how he'll stand up to "over confidence" when a they meet again this Friday?

(I...

by tab-tech
Replies
27
Views
2,479

Ouch..................................

.........touch'e.
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