hunting???

[Friobernal]

Hi;

I´m reading an english paper and i don´t understand the following:

Thermostatic expansion valve operation requiere condensing pressure control, to ensure a minimum pressure-difference over the expansion valve. Too low pressure-differences result in hunting.

What does hunting mean here??

Rgrds

[chemi-cool]

hi Friobernal,

hunting is a term used to identify the changes in refrigerant flow through the TEV.

it will open too much, allowing too much refrigerant into the evaporator and then close too much restricting the flow.

maintaining the condensing pressure high enough, will avoid hunting.


chemi

[Peter_1]

http://rc.danfoss.com/SW/RC_Training...f/rz1ah202.pdf

See page 12

[Argus]

Friobernal

In this context it is term borrowed from the automotive industry that describes an oscillation encountered originally in a poorly adjusted engine timing system that allowed the carburettor to open and close. The engine would speed up and slow down rapidly.

Used in the context of a TEV it describes either a poorly sized evaporator / TEV combination or a defect in the TEV that allows it to adjust wildly ranging, from flooding to starving the coil. You will see it on your gauges as an oscillation in pressure. There are a number of things that can cause it.

One thing is certain - you don't want it!

Hope it helps.
________
Traverse