R22 TXV With R290

[Trent04]

Hello! :)

I am planing a phase water chiller as my first build and was looking for some infromation on TXV's. I want to use a TXV so I have experience with them for future cascades I might try to build. I am most likely use R290 (BBQ Propane) for a referigant in my chiller since its going to be easiest for my to get and cheapest for me to replace if I mess up and need to regas. IS it okay to use a R22 TXV, that the only reference to a R290 TXV I could find in searching these forums. Also what do I need to look for when selecting a TEV, I understand the Ton to Watt conversion that was provided in the stickies but the other things kinda confuse me. If anyone knows a good guide to TXV's on the net a link would be greatly appreciated, or if anyone would make a guide for the site that would be even better!

Thanks for any help you can provide and I am sure I will be asking more questions soon and I will make sure I make a worklog of my build when I get all my peices!!

[PhilippF]

http://rc.danfoss.com/TechnicalInfo/literature/manuals/01/PF000G102_chapter_01.pdf

http://rc.danfoss.com/TechnicalInfo/literature/manuals/01/DKRCCPDAA0A302.pdf

I think you will be fine with a R22 TXV using 290. Ok, its not perfect but it will work.

Regards,

Philipp

[Xeon th MG Pony]

It will work fine no if's in it, the pressures are so close.

[Xeon th MG Pony]

http://hvacwebtech.com/marksM2.htm

http://www.refrigtech.com/charge.html

http://www.hvacrinfo.com/ae_index.htm

[Trent04]

Sweet thanks guys now I need to find a good plaace to buy a TXV, McMaster didn't have any that would work. . . Any Suggestions??

[sjg0]

Sweet thanks guys now I need to find a good plaace to buy a TXV, McMaster didn't have any that would work. . . Any Suggestions??

Ebay?

[Trent04]

I didn't really see much on eBay and the ones I did see didn't have alot of specs

[PhilippF]

Get a Danfoss TEV. Get a TX2 and also get a 00 and a 01 orifice. Also get a soldering adaptor.

I can recommend www.kaeltetechnik-shop.at which is run by Cold_Ice, you can drop him a PM in English. Or wait for one on Ebay.

Regards,

Philipp

http://rc.danfoss.com/TechnicalInfo/literature/manuals/01/DKRCCPDAA0A302.pdf

[DetroitAC]

Are you in the US Trent? R22 TXVs are everywhere and at bargain prices. Your best bet is to figure out the TXV you want from Alco, Sporlan, Parker, or Danfoss and then find it on ebay by model number. I also recommend you review Sporlan's guide to TXV selection if you're in the US.

You also need to figure out what your cooling capacity will be so that you can choose the correct size TXV. It'll be a bit tricky, R290 and R22 have different liquid densities, and different enthalpy change in the evap. The result is that a TXV rated for R22 but used with R290 will have ~3.5 times the capacity. (that was a real quick back of the envelope calculation, maybe someone could confirm...)

The bulb charge for an R22 TXV should work just fine with R290. Superheat will be a bit off, but probably not enough to need to adjust the valve.

[Trent04]

Thanks Detroit!!!

Sorry, I am just starting to fill out my profile and get active on the forums and will be working on my profile details.
If I go with a Danfoss TX2 with a 0X Orifice then I will have a cooling capacity of about 1600 Watts, Which is a tad more then I think I can even generate with my PC. :D

I was thinking of something like this (http://www.rparts.com/Catalog/Major_Components/holdover_plates/holdover_plates.asp) And then run the refrigerant through one side and the water through the other and cycle the compressor on and off with a thermostat, so would the TX2 with the 0X orifice

[DetroitAC]

If I go with a Danfoss TX2 with a 0X Orifice then I will have a cooling capacity of about 1600 Watts,


Do you mean that your compressor is capable of 1600 Watts cooling? If so it's far too big. Or did you mean that the TXV has has that much capacity? You will have to choose a TXV that has a capacity appropriate to the rest of your hardware. Too big is bad, too small is bad, what you need is one that's just right :D

What compressor are you going to use?
What will your actual heat load be?
What temperature do you want to operate at?

A holdover plate is really overkill for what you're trying to do. They are used in a mobile fridge or freezer to act as an evaporator. You can do the same thing with an insulated reservoir of calcium chloride/water and at 1/10 the price of those nice stainless steel tig welded holdover plates. Those things are built to last for 30 years in the icebox of a boat.

[teyber]

for txv's-

check grainger

Lots of refrigerant tech people around here have em

ebay, BUT GET THE RIGHT TONNAGE

the best quality bet is a danfoss tx2 (what about the te line?). philipf is always right :p:

[andre X_X]

ok, sorry to hijack your thread but i dont wanna make new thread for almost same question :)

i have a cascade with R22/CO2 blend on 2nd stage, do you phase change master think that i can use TXV with that refrigerant??? thx :)

[teyber]

I would just use cap tube on second stage, txv on first. cap on both stages just fine but txv on first is luxury :)

[andre X_X]

ok, i use R502 on 1st stage and would like to use TXV, i have Danfoss TEY2 R502 (http://cgi.ebay.it/Danfoss-Therm-Exp-Valve-TEY2-R502_W0QQcmdZViewItemQQitemZ300224689009)... currently thats the only i got here... what orifice should i use? thx :)
anyone has links on how to use TXV?? thank :)

[Clemmaster]

You also need to figure out what your cooling capacity will be so that you can choose the correct size TXV. It'll be a bit tricky, R290 and R22 have different liquid densities, and different enthalpy change in the evap. The result is that a TXV rated for R22 but used with R290 will have ~3.5 times the capacity. (that was a real quick back of the envelope calculation, maybe someone could confirm...)

The bulb charge for an R22 TXV should work just fine with R290. Superheat will be a bit off, but probably not enough to need to adjust the valve.

@-4x/-3x range, R22 has 90% higher massflow and propan has 70% larger enthalpie change.

But I was wondering, assuming both gases has very close pressures at our usual working temperatures (-50°C --> -20°C), maybe the bulb would do the regulation almost the same in both cases?

In the end will be massflow so much important for the regulation and for the choice of the orifice? :confused:

Maybe you would have to choose a lower rated orifice for propane?

[DetroitAC]

Thanks for the confirm Clemmaster

[Trent04]

I just bought this from ebay (http://cgi.ebay.com/NEW-5238-BTU-Air-Conditioner-Compressor_W0QQitemZ140257629690QQihZ004QQcategory Z53300QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)

The info from the auction is: R-22 refrigerant, Whirlpool part number 1188418. 5238 BTU
I will look put mfg specs if I find any later.

[Shingoshi]

I just bought this from ebay (http://cgi.ebay.com/NEW-5238-BTU-Air-Conditioner-Compressor_W0QQitemZ140257629690QQihZ004QQcategory Z53300QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)

The info from the auction is: R-22 refrigerant, Whirlpool part number 1188418. 5238 BTU
I will look put mfg specs if I find any later.
But I am now looking at the very same compressor. And I need to know if anyone has any specs on this unit? I'm considering using multiple units to achieve higher performance to make up for not getting a Danfoss SC18CLX.2.

Is propane the only other alternative for this? Or could I use r404a, r407a or r410a? How well would one of these compressors work in an autocascade?

Actually, propane looks like a very good choice. So what about this unit in my project?
http://www.xtremesystems.org/forums/showthread.php?p=3946925#post3946925

Shingoshi