Trimming Absorbers.

[RichardL]

"Trimming" an absorption chiller that is already on-line is not as easy as measuring the amount of Li-Br...
As the pump seal rings & Labyrinths wear, the charge must be adjusted to compensate for the lower flow of Li-Br to the Generator/Concentrator...
Regardless of make-model-manufacturer there are certain parameters that are virtually identical, with the main, most important being the "Spread" of Li-Br..
The term "Spread" has but one meaning on Absorbers and that is the Strong Sol. vs. Weak Sol. @ full load..
Soooooo.. when Solution pump starts to degrade(Pumping Less) the charge is adjusted to increase the capacity(flow-rate) on the solution pump...
Soooo.. if you find one running say.... a 6-7% spread @ load, you are bordeline with going solid and the flow must be increased either by a complete rebuil of solution pump(s) or temporarily readjusting solution charge to keep chiller on-line until such time a overhaul can be scheduled..
These wonders are not at all like sticking ref. in a Recip. package unit & walking away...
That is why the few Absorber Guru's that are still available are held in high esteem by one and all..

[absrbrtek]

This is so true. On a machine thats been in service there is no "weighing in" the charges. Its either you know how to trim it out or you don't. It can be a real challange at times depending on why your recharging the machine or trimming the machine.

The only time that "weighing in" the charges may get you close to a proper trim is on a brand new machine with nothing in it. Close being the optimum word here. Youll still need to trim it properly.

[Randy S.]

We just cut up the last of our absorbers last winter.

Nowadays when I think I smell alcohol, it's just somebody's hydraulic lunch.

[Randy S.]

Got some pump bearings and some various gaskets that are headed for the dumpster. Nobody out this way runs absorbers any more.

[_knight_]

Hey I don't work on chillers, but can anyone fill me in on what 'trimming' means?

[absrbrtek]

I'll take it. I think you have my email addy already.


Originally posted by Randy S.
Got some pump bearings and some various gaskets that are headed for the dumpster. Nobody out this way runs absorbers any more.

[Carrene #2]

Originally posted by ididntdoit
Hey I don't work on chillers, but can anyone fill me in on what 'trimming' means?

Ya, get out the chemistry set and start drawing samples from the chiller. Then add lithium bromide solution, or remove water ( refrigerant ) as required. Check chart for concentration etc..
Not that tough after a few times, but it can be very time consuming.