Everything you wanted to know about Variable Refrigerant Flow systems, from engineering, estimating and field installation techniques. You'll find the latest information on code and technical requirements.
I was trying to figure out how to determine the number of air changes you need for a specific room. Is it based all on code? Maybe Square footage? Where can you find that information?
Hello Sir, you explained back calculations only. First you declared 4 Air changes per hour and calculated CFM. Again same CFM value used for Air changes per hour calculations. Can you explain, how to calculate CFM without knowing the Air Changes per hour value?
Ive looked at a dozen references for the proper air changes per hour for different areas and every single one is different lol. Either super low or super high.
Nice video I have a question, I’m studying drafting , I’m just started learning about metric scale but what I don’t get how to convert example 1:80 scale into example (m, mm, or km) can you help me?
Hi, great video explanation. I need to know, what's in metrics formula? and what does it mean when the value of cooling coil total heat transfer is positive and negative?
Ventilation requirements can be found in ASHRAE 62.1 for Commercial Buildings and 62.2 for Residential Buildings. The use of residential bathroom and kitchen exhaust fans assist with any pollutants generated in those spaces, so it's important to make sure that those fans are operating when those spaces are being used.
I live in the land of leaky houses where air leakage is a MAJOR source of heat loss in winter. Do you have any actual evidence that the air infiltration is a small sum of the load in cooling mode?
We mostly handle large commercial properties. For an older home, infiltration or exfiltartion could be much greater, depending on the quality of construction, window and door types, etc.
Hello, I've been finding your video on calculating cooling loads extremely informative. I have some specific queries about the Solar Cooling Load (SCL) component of the calculation. I understand that SCL is influenced by factors such as the orientation of the glass, the month, and the time of day, and it's a dimensionless ratio typically ranging from 0 to 1. However, in your equation, you've utilized a value of 250 for the SCL. Could you please explain how this number was derived and why it's used instead of a value between 0 and 1? Is this value a constant, or does it change based on certain variables? If it does vary, how would I go about calculating or finding the appropriate value for my own home's specific conditions? Your clarification on these matters would be greatly appreciated. Thank you for your time and assistance in advance!
Thank you sooo much for this. I've been searching online to understand this formula. Because I am a visual learner I have not understood it until I saw you demonstrate it. 😊😊
You're right, as with any new technology there are those that are early adopters, and those who stick to the security of doing things as they have always done them before.
That's great but I have a question, that 108 CFM that you got from your results, is the CFM that supplied for the room or that to be exahuasted outside the room as an return?
The 108 CFM is the amount of air that needs to be Exhausted from the space or Recirculated (Return Air) through filters in situations like cleanrooms. Hospitals have many rooms that require a certain amount of ventilation air indicated in Air Changes, and also a minimum amount of air to be recirculated indicated in ACH. The air change calculation is just an indication of how much air is to be replaced within the space, which can either be exhausted or recirculated out of the space and back again through filters or some other process, depending on the application.
Can you pressfit a txv in reachin cooler? LMAO😁😁, Fire watch? Que? All those times you encounter different pipe sizes, you cant press them eighter! Besides i will bet i am faster with brazing than the zoomleak, with the cutting and fitting checking marking and whatnot.
There are advantages and disadvantages to both methods. There are times when the use of a flame is at a disadvantages, like wise there are times when pressfit fittings are not the best choice as you point out.
Yes of course. Anything that effects the heat gain or heat loss to the space, including interior spaces that are unconditioned and share a wall with the conditioned space.
@@ekie85 If you want to change to a Heat Recovery System, you'll need to have the system redesigned as you'll need the Selector Boxes installed between the Outdoor and Indoor Units.
I dont get it, I thought for example the given is 4cm then to make it to 1:50 scale you will just multiply it by .50, So its 4x.50 = 2 meters. Am I right?
You can use an anemometer to measure the CFM coming out of your supply grille, then multiply by 60 (60 minutes in an hour) and then divide by the Total Cubic Feet of the Room.
If the floor above or below is air conditioned then there is no load. If you have a floor above or below that is not conditioned, like a garage, then you would do the same calculation with the heat gain and loss through the floor.
