Installation of Liquid Line Solenoid Valve

[aaronh]

Good afternnon all,

Our cold room solenoid valve seems to be 'sticking', what would be the correct procedure to replace the valve?

Obviously the system will need to be recovered, but not vacced out as the pipes will be opened up? Will i need to carry out a triple evac when the valve replacement has been completed? Whats best flared fittings with threads or brazed? The valve is brazed at present but was wondering if it is worth getting the replacement valve with flared threaded fittings!

What do you guys think?

[sedgy]

hi arronh, solenoid valve sticking?
I would shut down the liquid line service valve run unit with s-v open< energised< run untill suction psi is down to 2 psi swich off mains, fit new dryer, fit new s-v,diaphram and internal parts, there should be a 1-4inch flair for your vac pump on the bottom seated liquid line valve vac out to recomended torr, open liquid line valve LEAK TEST, all should be well , all the best

[aaronh]

Hi sedgy thanks for the response, so are you saying that i dont need to recover the refrigerant? I can just carry out a manual pump down and replace the valve that way? Thanks for the advice!

[taz24]

Hi sedgy thanks for the response, so are you saying that i dont need to recover the refrigerant? I can just carry out a manual pump down and replace the valve that way? Thanks for the advice!

Yes.


Sedgy explained very well and that is how most engineers would do it.

There is no ned to remove the refrigerant if you can manualy pump the system down.

Just make sure you close the suction valve before you break into the system.

Then conect your vac and vac out the evap and liquid line in one go.

All the best

taz.

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[sedgy]

hi aaronh , yes thats right, obviasly that was just a quick rundown , like I didnt say put gauges on , or turn on the mains , but you got the drift ? well done

[sedgy]

thanks taz , good point about the suction valve ,

[aaronh]

Lol thanks very much for the advice, I thought that if any brazing had to be carried out that the refrigerant had to be recovered? Is this then not the case?

I was going to recover the whole system, open her up, carry out the replacement then triple evac, then recharge etc etc. But its a lot quiker to manually pump down, suppose it saves recovering and recharging time. Thanks guys.

[taz24]

Lol thanks very much for the advice, I thought that if any brazing had to be carried out that the refrigerant had to be recovered? Is this then not the case?

I was going to recover the whole system, open her up, carry out the replacement then triple evac, then recharge etc etc. But its a lot quiker to manually pump down, suppose it saves recovering and recharging time. Thanks guys.

Aaronh what make valve is it.

If it is a well known make you can get replacement kits to replace the whole of the inards and therfore you do not have to braze unbraze..

But if you do change the thing for new as long as the refrigerant is safe then it maters not where it is.

taz.

Ps again I agree with Sedgy....

Fit the gauges first>>>

taz

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[aaronh]

I have no idea what make it is i am afraid, its off of a boat cold room. We normally just get replacements from stores, I will investigate to see if we can just replace the inards. Thanks again guys for your help it has been very gratefully recieved!

And taz I wont foget the gauges

[aaronh]

Just to add to the previous post, its a danfoss valve, we are now going to take the internals out of the good valve and put into the old one!

Happy Days

[taz24]

Just to add to the previous post, its a danfoss valve, we are now going to take the internals out of the good valve and put into the old one!

Happy Days

Most Danfoss have replaceent kits, Somthing like an EV 6 if I remember (EV6 is a 3/8 valve) different numbers differant sizes.

All the best taz..

.
Ps the modern ones are fitted with those star shaped TEK screws or what ever they are called. So make sure you have the correct size fitting before you start.

Older ones used to have the Allen screw type.

taz

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[taz24]

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Ps the Danfoss has a steel disc on the inside Under the diaphram.

It is very very important that goes in the same way it came out.

If you put it in upside down the diaprham will not work.


It curves down.


taz

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[aaronh]

Again thanks very much for the fantstic advice you have gone above and beyond your call of duty!

I am one step ahead of you with the star keys have got them with a ratchet system

However thanks for the information about the steel disc.

[aaronh]

Have just realised that to carry out a triple evac on the liquid line solenoid valve I will have to either energise the coil or lift the valve with a magnet, what procedure is best? and easiest? am guessing the magnet

[frank]

With the sort of questions you are asking around the forum I'm guessing that you are a student and not and engineer as stated in your profile? am I correct?

Are your questions part of your homework?