Only experienced referheads need reply

[mdharris68]

Bohn evap, solder in txv, with manually installed distributor orfice. Can any of you give me an idea what kind of symptoms would be showing if the wrong distributor orfice was installed, or more likely, none at all? Have a WI freezer, new customer, don't know any history except who installed. Any thoughts on the symptoms to look for would be appreciated. Thanks.

[absrbrtek]

LOL, I dont consider myself an experienced reeferhead so I won't post my answer.

[Special-K]

I don't smoke that stuff.

[jcrank]

I haven't seen it personally,but one of the guys I work with said that he forgot to put the orifice in an evaporator once, and It froze up very quickly. It took a call to Bohn to figure out what was going on.

[markwolf]

Not trying to be a jerk,but how backward is it to ask for a possible symptom rather that to post your specific problems with the unit?From a service point of view going into a problem with assumptions rather than the facts at hand can& will get you into trouble more often than not.IMO

[BigJon3475]

I like my sig....

[wannafreeze]

I consider myself experienced in searching at this forum. When I read my posts from last year I feel ashamed though. Here is a good link:
http://www.hvac-talk.com/vbb/showthr...hlight=orifice
http://www.heatcraftrpd.com/res/pdf/...stribution.pdf

[the mojo]

mdharris68, The Heatcraft Installation and Operation Manual Part No. 250011201 the book that everyone seems to chuck in the garbage that comes in the box with the new coil on page 8 has a work sheet to determine the correct nozzle based on the highest LL temps achieved,for your freezer coil.

[mdharris68]

Sorry for the term referhead, I tried to edit it after the fact but couldn't. Thanks for the replys.

[mdharris68]

Not trying to be a jerk,but how backward is it to ask for a possible symptom rather that to post your specific problems with the unit?From a service point of view going into a problem with assumptions rather than the facts at hand can& will get you into trouble more often than not.IMO

I am not the one working on this case, therefore no data to offer. It seems that if this problem had been seen before by at least a couple of people, they should have the same story. I know the facts, just looking to compare this problem with a similar known problem.

[mdharris68]

I consider myself experienced in searching at this forum. When I read my posts from last year I feel ashamed though. Here is a good link:
http://www.hvac-talk.com/vbb/showthr...hlight=orifice
http://www.heatcraftrpd.com/res/pdf/...stribution.pdf

Thanks, I tend to forget to search out the old stuff. I appreciate you taking the time to refer me to those links. The second one is very helpful.

[MikeySq]

is the orface really needed with a properly sized TEV

[jcrank]

I consider myself experienced in searching at this forum. When I read my posts from last year I feel ashamed though. Here is a good link:
http://www.hvac-talk.com/vbb/showthr...hlight=orifice
http://www.heatcraftrpd.com/res/pdf/...stribution.pdf

That is a very informative file, Thanks !!

[Dowadudda]

uneven feed of evap. Serious Valve Hunt. Improper feed of coil will cause oil logging and will cause flooding. It will not acheive temp.

Most people think an orfice is to do the restriction, and this is untrue. It requires delta P for it to work right, but the tonnage part of choosing it is based on how well it will do it's function.

The disributor orfice is what mixes the vapor and liquid that flashes after the expansion valve so it evenly feeds the distributor. As the gas exits the TXV and the pressure drop creates the gas to flash off, liquid portion of the flash tends to drop and vapor to rise. So as it barrels on through to the distributor we we want to have proper even loading to each distributor tube.

[Special-K]

is the orface really needed with a properly sized TEV

In a coil that was designed for an orifice...absolutely! That is what develops the spray pattern that causes even feeding to the distributer and proper atomization in the circuits.

[hvacmd2002]

Years ago, there was never an orifice put in. I'm not saying you don't need it now, just saying

[hvaccop]

distributor nozzles, aka orifices, will be found on larger coils to distribute ref. evenly since the coil has so much tubing.

[edward301]

I just put in a 20 ton Heatcraft/Climate Control refigeration system. They
left the orfice and clip out, had to get it overnighted.

Without it you will have very uneven distribution of refigerant, across the
evap coil.

Just look down in the distributor, you can see why the orfice is needed.

[mdharris68]

Thanks again.

[absrbrtek]

How many yrs ago? I can remember getting orifices 30 yrs ago.

Years ago, there was never an orifice put in. I'm not saying you don't need it now, just saying