txv icing

[spyder00087]

is it normal for ice buildup on txvs and distrib. tubes in a freezer application?

[spyder00087]

was this a dumb question?

[jpsmith1cm]

Yes on both counts.



Not really.

Think about it for a couple of minutes and you won't have to ask the question.

What is your box temp? -10F?

So, to get a -10 box, you need about a -20 coil. Even with 6 degrees of superheat, you are looking at leaving suction line temps of -14 degrees.

If there isn't ice on the lines, you've got a problem. Heck, if there isn't ice on the COMPRESSOR you might want to take a look at it.

[maints]

If you have excessive frosting or ice build up on the inlet of the valve body you may have a plugged strainer. It can't hurt to pump it down and have a look at the strainer.

[Phase Loss]

This depends...

If you have ice on the valve and distributor tubes AND you have 6* superheat, your golden.

If you have ice on the valve and distributor tubes AND you have 30* superheat, you got a problem.

[man from trane]

Hmmm...I've seen TXVs in freezer evaps that were perfectly dry, and others with 12 inches of ice buildup in the same application. I've never known why some build ice and some don't, but they keep on working so I don't think about it too much.

[crackertech]

Hmmm...I've seen TXVs in freezer evaps that were perfectly dry, and others with 12 inches of ice buildup in the same application. I've never known why some build ice and some don't, but they keep on working so I don't think about it too much.

Don't fix it if it ain't broke.

[maints]

Also depends on the type of defrost.

Electric defrost in freezer cases never clear all the frost and ice off the distribution tubes. Bottom line is superheat.

[millo007]

The valve should be insulated this will prevent ice on the valve. You will get frost on the distribution pipes.