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CHIEF DELPAC
13-02-2009, 05:34 PM
I have a NH3 liquid sub cooler which cools the liquid feed to 2 30 ton brine chillers. The liquid level in the sub cooler is controlled by a Sporlan Level Master. I was explaining how the sub cooler worked in the freezing system to a new engineer, when I was asked what does TX stand for? I am wondering does it mean what I think it means or is their another definition? C.D.
nh3wizard
13-02-2009, 05:53 PM
? Thermal Expansion Valve ?
A thermal expansion valve (often abbreviated as TXV or TX valve) is a component in an air conditioning (http://dictionary.babylon.com/air%20conditioning#!!ARV6FUJ2JP) system that controls the rate at which liquid refrigerant can flow into an evaporator (http://dictionary.babylon.com/evaporator#!!ARV6FUJ2JP). This is accomplished by use of a temperature sensing device that causes the valve to open or close as temperature changes in the evaporator. An air conditioning system with a TX valve is often more efficient than other designs that do not use one.
US Iceman
13-02-2009, 06:13 PM
Chief, A Sporlan Level Master look almost identical to a TXV. These are not intended to control superheat like you would expect a TXV to control. A Level Master has an electric element which is placed in a vessel etc. to measure liquid level. As the liquid level decreases the element heater grows warmer which forces the valve to open and allow more liquid to flow into the vessel. As the liquid level rises the element is submerged and cooled by the increase in liquid lvel. This forces th evalve to close down.

It may be shown on a P&I drawing as a TXV simply because someone did not know the difference when they drew it. It could be confused to be a TXV because the valve body is no different than a normal TXV also.
CHIEF DELPAC
13-02-2009, 07:26 PM
nh3wizard, USIceman.Thanks for clearing up my misconception about TX valves. All of the engineers that I work with using the mans stuff oops I mean NH3 refer to the valves as TX valves rather than calling them flow regulating valves. I guess its easier to refer to them as TX valves.Anyway Thanks again C.D.