York process chiller repairs

[Matt]

The plant I'm working at is having a shutdown next week. I'm gearing up to do some repairs I've never done before.Everything is explosion proof so it's critical I get this "Hot Work" done during the week shut down, permits required etc.
York recip. chiller MODEL YCAZ33BA3 46PA
Two repairs, 1: York recommends changing the suction and discharge valve and springs every 5000 hours.
2: I suspect a refrigerant leak in the chiller barrel. I plan to open it up to plug and pressurize each tube.
I'm asking for any quick tips on either repair.Thanks

[FreezerGeezer]

Instead of plugging & pressure testing, how about having an eddy current test done? Much less work and a better answer to your question: "What state is the pipe bundle in?" as it will tell you which pipes aren't leaking, but will soon. This is the co. we use: http://www.hocking.com/

[chemi-cool]

hi matt,

what makes you think that there is a leak?

are there water in the crankcase?

york chillers tend to leak. ofcourse not all, but I have seen the backyard of a local chillers manufacturer. there is a mountain of them there.
if you cslose all the valves before and after the chiller and pressurise it with OFN and watch the pressure.

if there is a leak, you will have to replace the chiller.


chemi

[chemi-cool]

one more thing matt,

supose you right and you will find a leak in one of the pipes.
how are you going to repair it?
york use two heads chillers, that means that there is two slteel plates on both sides which the copper pipes connected to. it can not be pulled out.

if you are only going to open one side to see if there are water inside, do not forget to have a spare seal.


chemi

[Peter_1]

one more thing matt,

supose you right and you will find a leak in one of the pipes.
how are you going to repair it?
york use two heads chillers, that means that there is two slteel plates on both sides which the copper pipes connected to. it can not be pulled out.

if you are only going to open one side to see if there are water inside, do not forget to have a spare seal.


chemi

IN the past, if we had one pipe or two pipes which were leaking, we plugged them of with a brass plug with a steel conus plug inside.

[Matt]

Thanks for all the help!
The plant shut down isn't until the 29th of March, I have some time to come up with a game plan.
I suspect a leak because the chiller would lock out ckt. #1 on low suction. I have added refrigerant in the past over the years. I was so sure of a leak I recovered the charge, pressurized with dry nitrogen and a trace gas. I lost 30 lbs. overnight and 50 lbs. over the weekend for a total of 80 lbs. I have been over and over the piping with a Bacharac electronic detecter several times with no sign of a leak externally.I drained the chiller and then slowly filled the barrel while sniffing the air coming from a plug I removed at the top of the chiller. I still can't be 100% sure it's in the chiller.
The system is 10 years old, the only thing they put through it is city water, No inhibitors.In order to get a pressure drop across the chiller I had to remove and clean the pipe nipples to the pressure gauges, they were rusted shut. I put new gauges on.
I tend to be more cautious than to jump to conclusions. I don't want to open up the chiller only to find the leak is elsewhere.
I never did the eddie current check, I will look into that.
Thanks everyone, I will follow up with " The Rest of the story" (Paul Harvey)
Matt