Results 1 to 17 of 17
-
27-03-2008, 02:49 PM #1
Compressor Pressures at High Ambient Air
If you have the following A/C system requirement:
Continuous operation at 130F Outside Air, 80F Dry Bulb/67F Wet Bulb Indoor Air
What can you expect your evaporating and condensing temperatures to be?
I am guessing about 160F condensing and 50F evaporating.
How would an initial surge of hot ambient air affect the evaporating temperature? In other words, if you started with your return air temp at 130F, would the evaporating temperature be high and how quickly would it come under control?
How much higher would a blocked filter drive the condensing and evaporating temperatures at this high ambient condition?
- Andreas
-
27-03-2008, 04:00 PM #2
Re: Compressor Pressures at High Ambient Air
-
27-03-2008, 04:24 PM #3
Re: Compressor Pressures at High Ambient Air
We make air conditioning systems for locomotives. The system is contained in one box, like a large scale window A/C unit. We are trying to get a rough idea of the compressor amp draw at that high ambient air condition, 130F, to size our electronics. I am trying to make the connection from the high air temperature to the compressor suction and discharge pressures. There is also the concern of the blocked filter and how this would drive up compressor pressures. In addition, we wonder what would happen initially if the locomotive cab is also at 130F.
-
27-03-2008, 05:51 PM #4
Re: Compressor Pressures at High Ambient Air
I assume you are referring to a blocked refrigerant filter/drier, not a blocked air filter?
-
27-03-2008, 06:17 PM #5
Re: Compressor Pressures at High Ambient Air
dirty condenser filter is what I meant
-
27-03-2008, 07:48 PM #6
Re: Compressor Pressures at High Ambient Air
That's still not clear. Are we talking about an air filter or a refrigerant filter? (Yes, there is such a thing as a condenser air filter)
-
27-03-2008, 08:16 PM #7
Re: Compressor Pressures at High Ambient Air
condenser air filter
-
27-03-2008, 10:00 PM #8
Re: Compressor Pressures at High Ambient Air
Condensing temperature runs 20-35F over ambient, depending upon condenser size and airflow. Any blockage of airflow, such as a blocked condenser air filter, will add to this.
The low side pressure can be limited by MOP charge in the TXV and/or a CPR valve.
You might want to reconsider switching to R410A. At those temperatures, the pressures are going to be horrendous. You will need heavy duty everything.Last edited by Gary; 27-03-2008 at 10:05 PM.
-
28-03-2008, 11:46 AM #9
Re: Compressor Pressures at High Ambient Air
Hello all
do you think that using R134A for that application is way off also just thinking ? if not why not ? thanksHe who does nothing does nothing wrong !
-
28-03-2008, 11:58 AM #10
Re: Compressor Pressures at High Ambient Air
r134a wouldn't be bad, there's a reason why they use it in cars, high ambients and load, and the fact that you don't need a low evap temp for a/c.
wait: who even mentioned the refrigerant, I re-read the post and the OP didn't even mention it.Last edited by paul_h; 28-03-2008 at 12:00 PM.
-
28-03-2008, 12:00 PM #11
Re: Compressor Pressures at High Ambient Air
thanks paul does that mean i get a brownie points im sure other with say im wrong
He who does nothing does nothing wrong !
-
28-03-2008, 12:09 PM #12
Re: Compressor Pressures at High Ambient Air
hello all i know he didnt mention the type of gas but gary said you would be better of using r410a for that application but i was thinking r134a would be better for that application as you said we use it in cars high temps and heat loads
cheers
declan ps im bored in madrid with no workHe who does nothing does nothing wrong !
-
28-03-2008, 12:18 PM #13
Re: Compressor Pressures at High Ambient Air
Thanks for the information, especially to Gary. The refrigerant is 134a.
-
28-03-2008, 12:56 PM #14
Re: Compressor Pressures at High Ambient Air
-
18-04-2008, 07:30 AM #15
Question : How to post a new one here..
plz help me i dont know how to post in forums.. im a newbie here so please help me. i have lots of questions to ask thats why i want to know how to post in forums.
-
18-04-2008, 09:27 AM #16
- Join Date
- Sep 2007
- Location
- Split Croatia
- Age
- 57
- Posts
- 6,151
- Blog Entries
- 6
- Rep Power
- 36
Re: Question : How to post a new one here..
And, you are just posted, as you see.
Go to forum relevant to your subject:
http://www.refrigeration-engineer.com/forums/index.php
And hit New Thread button on top of opened page.
-
18-04-2008, 09:28 AM #17
Re: Compressor Pressures at High Ambient Air
Read this forum.
http://www.refrigeration-engineer.co...splay.php?f=25
And specifically this post I wrote about basic navigation
http://www.refrigeration-engineer.co...77&postcount=2
Similar Threads
-
Compressor loading, cooling, and range of operation.
By Air duster in forum FundamentalsReplies: 10Last Post: 02-04-2008, 08:39 AM -
Air Cooled Mono Block Units & high Ambient
By smpsmp45 in forum Technical DiscussionsReplies: 4Last Post: 11-12-2007, 06:29 AM -
TK basic micro-p features and functions
By REEFER-TEK in forum TransportReplies: 0Last Post: 05-12-2007, 06:25 PM -
fun quiz
By Brian23 in forum New to REReplies: 6Last Post: 02-10-2007, 10:18 PM -
Head Pressure: How High is Too High?
By HHC in forum FundamentalsReplies: 7Last Post: 15-07-2006, 05:23 PM