View Full Version : Defrost condensate lines

28-06-2008, 07:22 AM
I am attaching a sketch from a paper which shows Defrost condensate lines. I am unable to understand what it means. Of course US ICEMAN & others can throw more light on this.( I am unable to attach the file as it shows the limit is exceeded- how to overcome this point?)

28-06-2008, 09:39 AM
Greetings SANJAY.

Slightly confused by your question
defrost condensate Lines are usually a posh name for Defrost Drain Lines.

But I am not sure as to whether that was your question.
Welcome to the "UPLOAD FILES FULL" CLUB.
Cheers Grizzly

US Iceman
28-06-2008, 03:33 PM
This is where the english gets confusing for the terms we use in various locations. Are you talking about the water drain lines off of the drain pans or the drain line for hot gas defrost? I've heard it reffered to as a condensate drain line also.

On the other question, I'll have to ask the boss and see what he says...

US Iceman
28-06-2008, 03:48 PM
I just saw your file that was emailed to me. I'll take a look at it and reply shortly.

On the file limit issue... The file sizes have to be less than 100kb to be uploaded. Yours was almost twice that. This is why it failed.

US Iceman
28-06-2008, 03:57 PM
The line you are referring to is the hot gas condensate drain line. It is one of the various ways we can work with hot gas defrosts systems. Some hot gas defrost systems use a 3-pipe system: liquid, suction, and hot gas only. Other designs can use a 4-pipe system: liquid, suction, hot gas supply, and hot gas defrost condensate.

The drawings also show what they call up feed and down feed??? This is just another way to describe top feed or bottom feed.

The whole purpose of this line is to drain the condensed hot gas and remove it from the coil so that more hot gas can condense thereby warming the coil.

On the drawing you might separate it into two files or just scan it in B&W with higher resolution. The B&W file sizes are considerably smaller.

chillin out
28-06-2008, 04:30 PM
Upload your picture here...

And then paste the link.


30-06-2008, 05:27 AM
Sorry for some confusion. THe file was less than 100 KB when I was trying to upload >It could not be though. Now I have th elink to that article & infact there are many articles on that issue. There the COndensate line is shown separately. That is so confusing. Though US Iceman has given a well though explaination on that.
Infact there is one more interesting article & I shall get the data on that too.
But more you try to fine out the details, more confusing it becomes.!!!!


US Iceman
30-06-2008, 03:11 PM
If you use a 4-pipe system then you can return the condensate line back to the intercooler (for low temp systems) or to a vessel that simply operates at a pressure slightly lower than the defrost relief valve pressure.

In a 3-pipe system the defrost condensate is simply returned to the suction line on the specific evaporator to a location downstream of the suction stop valve (usually a gas powered check valve).

01-07-2008, 06:55 AM
Many thanks for the Clarifications. We had never used such system earlier.

US Iceman
01-07-2008, 03:15 PM
The 4-pipe system is a way to decrease the energy use of the system since the defrost condensate & flash gas formed from the expansion of higher pressure liquid down to a lower pressure generates higher vapor volumes which the low stage compressor must pump. If you take the defrost condensate to a much higher pressure than the low stage suction pressure the energy use can be decreased considerably.

More piping for less energy use...;)

01-07-2008, 04:22 PM
Now that seems more logical.