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weagle
25-01-2012, 12:52 AM
Your going through a maintenance procedure on a rotary screw compressor. Its summertime and the load is on the plant no time to shut the compressor down.You need to take an oil sample from the compressor..The question is where do you pull the sample from? AND How do you prevent a foam bath of oil?God knows I been in this situation before try to take an oil sample from a service port and have the sample bottle fly out of your hand and get oil all over the floor.Would like to know any tips!

HVACRsaurus
25-01-2012, 09:25 AM
Clean bucket. Draw oil from whatever point you have, put a decent amount into your bucket, wait for it to liquefy and pour it into your sample bottle before it absorbs too much moisture.

weagle
26-01-2012, 12:09 AM
OK.. that's a given answer but i was wondering If there was more of of a clever idea. Thanks anyway.

install monkey
26-01-2012, 12:14 AM
pump the compressor down-less pressure and hopefully there is a drain point on the sump as opposed to a drain plug

monkey spanners
26-01-2012, 12:37 AM
Drain some oil into a clean recovery bottle (or pipe thingy you've made yourself (end caps, big diameter pipe, shrader things), or a small reciever) wait for it to settle and vent excess refrigerant pressure back into the system. Puff oil out into sample bottle with some ofn. (assuming you are taking sample from high pressure oil line)

RANGER1
26-01-2012, 01:35 AM
Sometimes there is no easy simple answer.

If a bottle is going to fly out of your hands & oil everywhere i can only suggest following assuming its a ammonia system.

Use a larger sample bottle
Have a steel 1/4" tube connected to drain point into sample bottle
Put sample bottle in a larger bucket to catch any spills

note - An oil sample should really be taken while unit is running
- Sample point should be drained a bit to clear any possible sediment .
- Sample bottle can be flushed with oil from sample point to flush any possible contaminents from
bottle, especially if you are then going to transfer it again into smaller sample bottle to send away
-Sample point should be before filters if you want to know of whats floating around. Some filters like
Frick are only 5 micron

Vent oil in at desired rate into sample bottle over a few minutes

weagle
30-01-2012, 01:36 AM
Drain some oil into a clean recovery bottle (or pipe thingy you've made yourself (end caps, big diameter pipe, shrader things), or a small reciever) wait for it to settle and vent excess refrigerant pressure back into the system. Puff oil out into sample bottle with some ofn. (assuming you are taking sample from high pressure oil line)

Now that was a suggestion I was waiting for! Thank you!

Tesla
30-01-2012, 08:06 AM
Brilliant monkey for the answer and brilliant weagle for asking the question.
I have had a lot of the foam bathes and wa looking for a solution. The thingy you have described monkey I think I have recently bought - it's a yellow jacket oil charging cylender which holds about 150cc for little systems and I used to use the thingy you mentioned 20 years ago for charging oil. Cool guys.

Nh34life
24-03-2012, 10:45 PM
Sampling oil into a receptacle other than a lab provided bottle will give false readings, do not use hose either as this will hold contaminants from other sets.
Correct method as stated by oil testing lab:
Compressor must be running
Sample before filters
Clean sample point service valve
Install 1/4" reg valve into sample point service valve
Purge sample point into a bucket to minimise sample contamination
Remove sample bottle lid and place down top side up on a clean rag
Fill bottle, If foaming occurs, tap and swill bottle until it clears (not lab
but this works well)
Repeat until bottle full
Replace cap do not tighten for 1/2 hour
Tighten cap send for analysis.