Install Danfoss TEV

[SkyWalker]

hi guys just a quickie, i have a danfoss TEV to install in a couple of weeks and the connections are bi-metal, stainless steel outer and copper internal, my question is should i use 40% silver solder/flux to make my conection or should i "braze" it with standard 2% silver (at least 2% is our standard?

i checked on there web site but it just says solder connection not too sure what they mean by this. any help is much appreciated, thank you.

ow also while im on the subject, is it normal to lag the external equalization line if the TEV requires it, as this will be as low 1 - 5*c on this install? (R410A Comfort Cooling Air con)

cheers guys.

[nike123]

I would go with 40% because of lower thermal stress at valve (lower melting point).

[chemi-cool]

both will do.

The 40% silver is easier and faster . but if you use the 2 % Silfus and add flux powder, no problems just keep the TEV wrapped with a wet piece of cloth.

[SkyWalker]

cheers guys much appreciated, what about lagging the equalizing line, is this normally done

[nike123]

cheers guys much appreciated, what about lagging the equalizing line, is this normally done

I would say no, it is usually not done.

[marc5180]

Just installed one of these today and had a nightmare trying to braize it with the 2% silver whilst trying to keep the valve cooled.
Why do manufacturers not make the stubbs just a little bit longer to make it easier to install them

I'd go for the 40% silver much easier but at £3 a stick very expensive.

[Miles Brennan]

Don't use your 2% braze alloy (2%Silver/Copper/Phosphorus on the stainless steel - it is not designed for this and you will get failed joints as the Phosphorous forms a brittle intermetallic with the iron in the SS.
If standard 40%Silver is all you have then I guess use this, but it would be preferable to use an alloy with some Nickel in it such as IPM50N as this reduces the chance of interfacial/crevice corrosion.
If you need further help - contact me miles.brennan@blueyonder.co.uk