Trane PCV side winder Surging
MN: PCV4F-C1D2/SN: L4K18558
I Can not load the Machine with out it Surging operating pressures/temps.
In-cond. water temp.-71deg
out-cond. water temp-72 deg
in-chilled water temp-54 deg
out-chilled water temp-52 deg
discharge gas temp-163deg.
condenser temp-76deg(before the orifice plate)
After the orifice plate-72deg
evap. suction temp 53deg
Condenser pressure 4#
Evap pressure 10'' hg
cond. satur. refrig temp-87deg
evap satur.refrig. temp-53deg
is there a bypass?
how can you raise the condenser water temperature?
is your purge working?
what is your purge rate?
I assume you are not all aired up cus your head is low?
without a pt chartr, it looks like your condenser water approach is good?
The pressure-temperature information you have provided suggests that the machine contains R-11. The approach temp seems very high (87 degree sat. cond. - 72 degree leaving h2o temp = 15 degrees) given that your evaporator delta T is only 2 degrees. I strongly suspect non-condensables, I would check purge operation first.
Need to know the water flow in condenser, you have air or water issue, maybe dirty tubes.
Wow! Old machine. Over 30 yrs. Seems to have air in it. Do a hot water leak test. If leaks are found, discuss with owner if it is worth it to tear down such an old chiller. Test purge effectiveness. Is it still belt drive? There is always vacuseal as a temp leak repair. Many parts are no longer supported on that chiller.
As I remember, these machines didn't run very well lightly loaded.
Also if the inlet vane bushings get worn the operator sticks, then hunts like the devil, and will surge on the unload transitions.
Also don't discount that it isn't a problem with the vane control itself, we used a pneumatic operator and had a spring that connected to a device that slowed down the action, to prevent hunting. Too much dirty or wet air will make these devices misbehave.
All my money is on both condenser tube fouling and non-condensibles. Probably split 70/30, though. 15 degree condenser approach is bad. All of the R-11 chillers I've worked with that got really filled up with air ran much higher than 4# condenser pressure. Most don't start surging until they get in the 7# to 10# range. It's rare, but I've seen some actually trip the high pressure switch.
The key to happiness is lower expectations.
I agree with the other posts, your condenser approach is too high. What percent load are the readings taken at? If your running that low tower temps and still getting 4 psi at say 50-60% your problem lies in your condenser. Verify your flows, I am going with air in the system- check purge. Someone else mentioned too low condenser water very true, 80-85 with these old machines helps with oil return.
Sic Semper Tyrannis.
I like the non-obvious.
Is the pin broke on one of the vane assemblies? (common)
Is the divider in the condenser head still intacked?(not common)
"I'm from Texas, what country are you from?"
Im with sticker and also the non condensables .
Originally Posted by stickerhead
All gaskets still available no old pneumatic control panel parts available . time to convert/update her or scrap her .
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Is this chiller's Discharge Superheat calculated using Condensing Saturated Temp. or Discharge Saturated Temp.? If it's Condensing, then your Discharge Superheat is 76 degrees. Very little if any refrigerant in the condenser. Your high Evaporator Approach can indicate an undercharge. Your high Condenser Approach probably means fouled tubes. Don't be afraid to open your Condenser up. Judging just by age, you may have an undercharge, non-condensables, & dirty Condenser tubes. Surging can be caused by any of these things. How's your Condenser Delta P? Check your purge, then your tubes. Go from there. Good luck.
I think I thru an extra saturated in there.
Originally Posted by supertek65