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Will turn www.example.com into [URL]http://www.example.com[/URL].
Heat exchangers &, piping contract & expand also….
Originally Posted by pecmsg Starting at 600# and 70* Ending at 65* You’ll loose 5#’s of pressure It’s accurate! and you know what is the temperature inside of the condenser, evaporator, line set in the ground etc.... no way
Originally Posted by VTP99 There was a PT chart for that floating around here somewhere The link above works too.
Originally Posted by VTP99 There was a PT chart for that floating around here somewhere Ice posted it!
There was a PT chart for that floating around here somewhere
Originally Posted by pecmsg Starting at 600# and 70* Ending at 65* You’ll loose 5#’s of pressure It’s accurate! Yep and even more accurate if you compensate for temperature.
Originally Posted by R600a But it definitely changes pressure. Starting at 600# and 70* Ending at 65* You’ll loose 5#’s of pressure It’s accurate!
Originally Posted by VTP99 Nitrogen is much more stable than refrigerant But it definitely changes pressure.
Nitrogen is much more stable than refrigerant
Originally Posted by gustavhorna over 24h the climatic conditions change too much for any useful conclusion. Pressure depends on temperature. Now if your temp changed 3F, is the drop by 20 psi a leak or temperature drop? You cant even measure the temp across all lines, indoor, outdoor etc. So no, more than 15-30 mins is not useful I use this calculator for long pressure tests for exactly this reason. https://www.oceanhvac.com/nitro.php
Originally Posted by rider77 Care to elaborate? over 24h the climatic conditions change too much for any useful conclusion. Pressure depends on temperature. Now if your temp changed 3F, is the drop by 20 psi a leak or temperature drop? You cant even measure the temp across all lines, indoor, outdoor etc. So no, more than 15-30 mins is not useful
On Deck 👇🏻
Before 👇🏻
Do it all the time. I'll be doing it in the next few days on a 4 ton heat pump. Should I take pictures 🖼️
Originally Posted by VTP99 I'm still hung up on the 12 hours to vacuum down a 4 ton system without pulling the cores [emoji44] I've never seen a proper vacuum pulled with the cores in and I don't believe it exists.
More like 12 minutes 😁
I'm still hung up on the 12 hours to vacuum down a 4 ton system without pulling the cores 😲
Originally Posted by gustavhorna nonsense Care to elaborate?
Originally Posted by shaggs2broke I think I have pinpointed my problem, the vacuum gage I purchased new appears to be defective. I suspected it after my overnight 620psi pressure test with no drop. i felt I should be able to hold vacuum with same setup but vacuum gage in place of pressure gage but couldn't say for sure until I used another vacuum gage. I pulled down to 20 microns and held it under 500 microns through 3 feet of 1/4" tubing for over an hour. As soon as I added my other vacuum gage and tried again it wouldn't hold at all. Damn CPS and their vacuum gages! There is such type of leak that leaks only in one direction. Holds pressure but leaks under vacuum (or vice versa). It's real
Originally Posted by rider77 Your pressure test is insufficient. Many manufactures call for over 500 PSI for as much as 24 hours. nonsense
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