Hi Guys,

Got a call out today, Message was "Dairy case high temp since engineer fitter TEX last week"

Just the call i like

The story so far, Check the enginners paperwork and indeed he replaced the expantion valve. The unit is an OLD !!!! Craig Nicol 12ft dairy with a copeland scroll condensing unit. Gas looked very low, hp 120 lp 10 nothing in sight glass. Leak tested coulnt find jack so topped up but was too busy looking at sightglass and overcharged. Now running at 300 HP and 60 LP. Sightglass however still flashing like mad and not flooding back. Check exp valve and frosting coming out but nothing at the other end of the coil on the knuckles. Tried adjusting valve at quarter increments, eventually had valve wound right out (5 Turns) still nothing. Check drier looks/feels OK only 0.1 degree C diff temp wise on the pipes and that might just be where i am holding the probe. Pumped down check the orrifice (No 4) no signs of burning and filter clear.

The only thing i can think is that the new exp valve is u/s. It is a Danfoss TES2 (R404) and is the same as the old one that was taken out as the old one is still there.

I plan to go out tommorow, pump down, change valve, Change drier, Vac out and see what happens.

I question is can anyone else thing os anything else that i may have overlooked


Regards

Raymond