What are your thoughts regarding insulating dust collection ducts that are located outdoors in the Northeast U.S.(14*F design DB)? Specifically, I have an application where ~ 200 ft of duct will be installed outdoors. Some people in my office suggest that the ducts be insulated to prevent...
What are your thoughts regarding insulating dust collection ducts that are located outdoors in the Northeast U.S.(14*F design DB)? Specifically, I have an application where ~ 200 ft of duct will be installed outdoors. Some people in my office suggest that the ducts be insulated to prevent...
So what's the problem? A fan will consume more power at a higher total pressure. Research fan affinity laws if you're unclear on this subject.
You may have some difficulty trying to get the info that you are looking for. You can try this website / manufacturer to get reasonably close to the...
Here is the Product Data Catalog for a 50XT Packaged Heat Pump.
http://www.docs.hvacpartners.com/idc/groups/public/documents/techlit/50xt-05pd.pdf
Page 29 has fan performance data
You answered questions 2& 3 on your own.
Sorry...just saw your thread title.
This may help get you started on your ITP. Some refer to this as systems commissioning.
http://www.peci.org/ftguide/
A 5 minute Google search....an wallahhhh....
http://74.125.95.132/search?q=cache:7P2C6ia2LmEJ:www.ilmechsales.com/products_items.asp%3FSubCategoryID%3D29+illinois+balancing+valves&cd=18&hl=en&ct=clnk&gl=us&client=firefox-a
Google the Manning Equation which is for open channel gravity flow. There is a table in the ASHRAE Fundamentals in Pipe Sizing for water flow (lb/hr) based on pipe pitch.
Here's the link to his articles.
http://bookstore.ashrae.biz/journal/journalsearch.php?limit=10&order=high&query=rishel
Also, I've attached the article on balancing valves.http://files.engineering.com/getfile.aspx?folder=42a8379d-8237-4649-8f63-df65fc9c8822&file=BalanceValves.pdf
My bad...the additional PD of the balancing valves would decrease the wire to water eff. The key is proper sizing of the CC control valves, which a vast majority of engineers & control contractors lack...but that's another subject.
Chris -
James "Burt" Richel published many ASHRAE articles on hydronic systems design and efficiency. He address this very subject in on article. His conclusion, balancing valves on only increase the wire to water efficiency of a variable flow CHW system. You can log in to ASHRAE's website...
My opinion is that if it is a variable flow system, balancing valves are not really serving any purpose, other than providing a means for measuring flow. If you have a constant flow system, you absolutely need a balancing valve.
I would contact Prefered Utilities, http://www.preferredutilities.com/
they manufacture fuel oil distribution components and know the applicable NFPA codes for your application.
Good Luck.
OK. You have a 3-way valve with a butterfly valve in the bypass, so that is fine.
"I ran a quick test on one of the air handlers the other day. With at least a 15 degree F temp difference between air flowing through the handler and the chilled water, withe the bypass balancing valve manually...
I am confused at your valve arrangement. In your last post you are implying that you have a 2-way control valve, but you also say that there is a balancing valve in the coil bypass. Is that what you have? If so it sounds like you have an incorrectly piped coil. Can you attached a sketch of...
Sometimes design engineers use the cooling coil as a moisture eliminator for the upstream humidifier (I personally don't). Theoretically, if the water vapoer has been fully absorbed in the airstream and the coil temperature is above the air/water vapor's dewpoint, there shouldn't be any...
If you're saying that the control valve (CV) does not fully shutoff flow when commanded to full bypass then maybe the actuator does not have the close-off pressure against the pump head. You should check what the close-off pressure is for the valve & actuator combination.
The balancing valve...
What is the specific criteria for providing pressure relief valves on building services piping according to B31.9?
I have a ground source heat pump system that currently does not have a relief valve on the well system. I was always under the impression that B31.9 required them if energy was...
