Yeah, he's confusing "Bleed" with equalize!!!:grin2:
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Mojo, If you hooked the 1/4" external equalizer line to a flare port with a schrader you need to go back and remedy your mistake. We all make mistakes and that is not a problem. However you need to step up and do what is right. Im glad to see you came here and asked the question. Good job.
ok, so you are saying the valves I am dealing with are internally equalized? If so what does the bleed port do?
I dont know what kind of valve your working on. Is there a 1/4" tube you braze into the suction line? IF so the Valve is externally equalized.
The bleed port is a hole in the valve that allows refrigerant to bypass the valve in the off cycle.
Did you start reading on Sporlan's site yet? Bulletin 10-9 and 10-10 will answer your questions. Take the time to read and understand them. If you need help ask the question. We will help.
internal eq. valves are found on small evaps such as reach-in coolers with little pressure drop!!! Here's a pdf from parker thats a little better than the one i posted earlier. http://www.parker.com/literature/Aft...V%20Theory.pdf
The valve that I am talking about replaced a valve that had a very small tube brazed into the suction line, that I thought was the external equalizer, and was replaced with a valve that had the same tube with a female flare and came with a 90 degree short piece of suction tube with the male threaded flare connection for, what I thought was the new equalization tube.
Go where you purchased the valve and have a look at the eq tube fitting. If it has no schrader depressor go back and remove tube. Add service tee with schrader depressor with eq tube connected to port with no schrader.
Or just pump it down and remove it.
the equalizer tube sees the suction pressure of the evaporator.
it takes the suction pressure and forces it on the spring of the diaphragm or bulb pressure.
if the equalizer tube were blocked there would be no pressure against the spring and the valve would be forced close which would give you a high superheat.
Think that's backwards
understand that its all based on what the equipment manufacture designed it for. Trane heatpump air handler coils come with the core in but you must remove it before you install the TXV. the equalizer cap tube with the flare end, is not equipped with a depressor. if you leave the core in and install the TXV and start the unit it will not equalize the TXV in respect to the evap coil causing problems with the performance of the TXV and overall system. I would follow the manufactures instructions. every one is different.
Read most of the PDF, a good one indeed, and figured out that it is 2 oppossing forces that control the flow of refrigerant, the charge in the bulb against the back pressure leaving the evaporator. So I guess I was wrong in my thinking that pressures equalize in a txv system, they don't? They do though equalize in a system using a piston as a metering device?