problem in ammonia thermosyphon system

[ghanghas85]

good after noon to all my refrigeration engineer frnds.Dear frnds i have 5 grasso screw comressors.one compresor -2 system ,1 for -10 ,1 for -30 system,2 for -38 system for their oil cooling i have given common header from ammonia thermosyphon reciever.all the compressor are running very well but in -10 system compressor the oil temp. goes suddenly high fron 45 degree celsius to 70 degree celsius and compressor goes trip.this problem takes place after 10 to 12 hour running.ammonia level in thermosyphon is sufficient,i also close all other oil cooler liquid supply valve shut off but i face same problem.please give yours valuable advise

[australian tech]

HI ghanghas, monitor the temperature of the thermosyphon in/out temp.
Is this a new installation, or a previously o.k. system.
Is there a balance line between the reciever and condenser.
oil pump flow rate? slide valve behaviour?
Im very keen to find out what is causing this.Please post what you find, I will talk with a friend tomorrow who has had a simmilar issue before.

[dolce]

I think there is oil in cooler with ammonia for 3 days this problem has happened in grasso compressor Gls 85 and i did that close inlet hand valve and outlet hand valve too there is drain valve in the bottom of the cooler joint it with a hose and other size of the hose to suction line to drain oil