Why the solinoid valve?

[r.bartlett]

Chaps had a look at a chiller yesterday

Why have they fitted a sol valve on the eql line or am I misreading what I see?

6723

[james10]

YORK YCAL O173 CHILLER UNIT, no idea why good valves though, are you aware it's an electronic expansion valve most people who first see them think they are tev's lol

[stufus]

It's not an equalizing line in the normal sense it's a pilot valve . I think but don't quote me on that ;)

[al]

when open it drives the expansion valve open, one thing to note it may be a 110v coil, being York n all. expansion valve works by applying heat to bulb of expansion valve which regulates flow, hybrid eev and tev!

Let me know if you're ever stuck for parts, local office here is really good.

alec

[frank]

Hi Richard

It's normal for a sol valve to be fitted on the LL in chillers as this stops liquid migration to the evap during off cycles. Similar to a pump down but without the pump down if you know what I mean.

[install monkey]

its a trane chiller so trane can charge u £200 for an new alco valve.(yorks are a darker shade of brown!)

[TTR_Tech]

Hi Guys,

Pretty sure that's a danfoss TGE valve or similar. Seen this done a few times before. If the solenoid valve in the equalizing line de-energized, high pressure refrigerant from the liquid inlet weeps past the pushrod, applying closing force to the diaphragm. Basically closing the TX valve via pilot. Normal superheat control is with solenoid energized. This application avoids the cost of a normal (larger) full flow solenoid valve.

[Magoo]

Carrier used to a similar thing with a three port solenoid , forced HP liquid ontop of TXV and forcing TXV closed.

[r.bartlett]

its a trane chiller so trane can charge u £200 for an new alco valve.(yorks are a darker shade of brown!)

It's been out in the sun for a few years. It is indeed York as ID'ed above..

[Peter_1]

You have to look once Richard if this line isn't connected to the HP and the valve is a small 3 way-valve? Then it's a setup like this where they use the TEV also as a SV.
James10, I'm almost sure this is a TGE valve and surely not an EEV.

But I don't think that refrigerant can weep across the pushrod. They're to good machined these days and they very rarely leak.Someone from Danfoss production told me this once and I posted this also here somewhere on RE (the discussion that it's better f mounting the bulb of a TEV after the equalizing line)

[r.bartlett]

YORK YCAL O173 CHILLER UNIT, no idea why good valves though, are you aware it's an electronic expansion valve most people who first see them think they are tev's lol


Well it certainly fooled me. I still cannot see it.:-/

[r.bartlett]

Hi Richard

It's normal for a sol valve to be fitted on the LL in chillers as this stops liquid migration to the evap during off cycles. Similar to a pump down but without the pump down if you know what I mean.

I get that Frank but this sol valve isn't shutting off the LL

[r.bartlett]

You have to look once Richard if this line isn't connected to the HP and the valve is a small 3 way-valve? Then it's a setup like this where they use the TEV also as a SV.
James10, I'm almost sure this is a TGE valve and surely not an EEV.

But I don't think that refrigerant can weep across the pushrod. They're to good machined these days and they very rarely leak.Someone from Danfoss production told me this once and I posted this also here somewhere on RE (the discussion that it's better f mounting the bulb of a TEV after the equalizing line)


I just had a brief visit to quote for the maintenance. I don't think it's an EEV as that wouldn't need a sol valve as it would be powered shut to give pumpdown/migration control?

[Grizzly]

Hi Richard.
I am not convinced you looked at a YCAL (These have scroll compressors)?
I am sure I have seen these on earlier models but cannot remember where?

Anyway as far as I understand York use these YLLSV (Solenoid valves for several purposes).
Some of which are :-
So that systems can be pumped down.
Also when the system is running and the Suction S/heat falls below 2.2c the valve will close (Coil de-energized).
When s/heat rises above 3.3c the coil is re-energized opening the valve again.

I think it's all to do with the low temperature running (Glycol ) options.

Grizzly

[james10]

Well it certainly fooled me. I still cannot see it.:-/
if you look on the underisde of the valve you'll see the electronic driver plug and in the millenium controller you can see the exv position

[Peter_1]

James10, if this is true, then it certainly interests me an I think others a lot. Can you post a link from this type of valve and controller? I was speculating for myself why this SV was inserted between the equalizing line but I will wait till I've seen your reply now.

[Peter_1]

There's clearly a bellow with an external bulb and if there should be somewhere a stepper or a PWM motor, then it should be mounted in the top where the bulb is located now. You can't control a Danfoss valve from the sides, only on the top.
This is a standard TEV with a fix orifice.
It can be that the SV is open to handle a normal SH and closed for a higher Sh, equal to the DP over the evaporator.
Or if the line is connected to a HP point, then this is done tot use the TEV also as an adapted SV.

Regarding this equalizing line, I will start another discussion in Fundamentals

[frank]

Sorry Richard, I didn't notice that you had posted a photo....Doh!

[al]

Richard

There is a heater attached which warms the phial on the TEV, it is a standard TEV in every other way, as posted above you can see the opening percentage on the display.

They also as Grizzly says shut the valve on low superheat, i have a YCAL with one, haven't seen one a new machine since.

Al

[Grizzly]

Hope this helps?
Grizzly

[Peter_1]

I humble bow down my head now, plow it then as deep as an ostrich due to Grizlly's last post. I learned a lot these time. Thanks Richard and Grizzly for this.

But then some questions arise while my head is in the sand: why they use such a valve and not a common EEV with stepper motors, PWM? What's the benefit of this?

[james10]

So are we at the conclusion that this is an unconventional EXV?:)
i didn't realise that it operated in the way the drawing described , nice to know

[TTR_Tech]

Everyone probably has it worked out, but useful info all the same...

http://york.com.ua/files/YCAL-SB.1093518638.pdf