I've been taking note lately, seeing many original Traulsen units using TXV's, R404, but no receiver and in a few cases, no sight glass. It was always my understanding, a liquid receiver is necessary when a TXV is used for metering. Can anyone enlighten me? Is this just Traulsen cutting corners, or figuring receivers not necessary for indoor equipment with relatively stable ambient temperatures?
Not necessary. Single circuit. They're not pumping the units down. Just a critically charged unit with better pull down capability than a cap tube. Sight glasses cost money.
Local 597 Service Fitter
Metal Trade Journeyman
PAY ME NOW OR PAY ME LATER
It was working when I left...
Liberalism-Ideas so good they mandate them
And if you really wanna get a discussion going, explain why they always pipe the driers vertically with the outlet at the top? Now when it comes to cap tubes, I've heard many say you need the drier outlet at the bottom to maintain a liquid seal. Traulsens typically use TXV's, but with drier outlet on the top, it makes you wonder how it is they work so dang well? (I'm a fan of Traulsen equipment myself.)
Seeing it on 10' prep tables with dual evaps, two txv's
What I meant by dual circuits is like a table with a well, running med and low temp circuits. What you're describing is no different than having 2 evaps with dual cap tubes, which Traulsen has also done.
I would bet the unit with the solenoid is definetly a pump down.
Local 597 Service Fitter
Metal Trade Journeyman
PAY ME NOW OR PAY ME LATER
It was working when I left...
Liberalism-Ideas so good they mandate them
You will rarely see an air conditioner with a receiver, but lots of them have txv's. An air conditioner is a type of refrigeration system. How does that work?
It is all about having a solid column of liquid going to the txv. To check that, look for subcooling. You don't need a receiver or a sight glass to measure it.
I worked on a Traulsen reach-in dual temp recently that used a single compressor. Refrigerator and Freezer both had evaporator with TXV. Liquid line solenoids allow each section to run independently. No receiver also. It was set up a little differently than most Traulsens, with evaporators on the left side of the box inside the wall. The left panel of the outside of the cabinet was removable for service.
And if you really wanna get a discussion going, explain why they always pipe the driers vertically with the outlet at the top? Now when it comes to cap tubes, I've heard many say you need the drier outlet at the bottom to maintain a liquid seal. Traulsens typically use TXV's, but with drier outlet on the top, it makes you wonder how it is they work so dang well? (I'm a fan of Traulsen equipment myself.)
I've never really bought into the whole idea that a tiny little liquid line drier in a cap tube cabinet needs to be pointed down to maintain a "liquid seal" at the cap tube.
You will rarely see an air conditioner with a receiver, but lots of them have txv's. An air conditioner is a type of refrigeration system. How does that work?
It is all about having a solid column of liquid going to the txv. To check that, look for subcooling. You don't need a receiver or a sight glass to measure it.
I certainly understand these basics. I was just asking....but let's say the Traulsens with this design are under a high load and the txv's are flowing larger amounts of refrigerant to maintain SH? Still no need for a liquid receiver?
Why does Copeland offer fractional indoor condensing units with or without the receiver? In this case, a 3/4hp skid? What would be a good example of where a condensing skid with a receiver be used if not necessary on a 10' prep table with two evaps?
Reply With Quote
Originally Posted by Capz
