Carrier absorbtion chiller

[Haden4ever]

Hi there, could do with some help re a Carrier chiller, from someone with a bit more experience of these voodoo machines :rolleyes: model number, 16JB 041, originally called to a tripping refrigerant pump, sorted that one and now within 0.5 amp of spec, solution pump seems to be drawing too much current and the chilled water TD is none existent, a previous worksheet from a Carrier engineer states that the generator hot water feed should be at least 90c, it is currently fed from a boiler set at about 70c, also the purge light has been reported as coming on regularly, does this indicate it requires vaccing? and if so what is the procedure for this? enough questions for now i think, would appreciate a bit of direction on this one, as you can see i normally play with proper fridge kit and i'm trying to get my head around this

cheers

[frank]

I'm not too familiar with Carrier Abs but generally speaking, all Abs need purging (non condensables) on a regular basis, weekly, monthly or otherwise to maintain the vacuum level.

If you are getting lots of non condensables then this could indicate a leak in the shell.

The non condensables are stored in the purge cylinder and you need to hook up a vacuum pump if there is not one built into the machine.

I would hazard a guess that the purge light you see is triggered by a rise in internal pressure. Without a deep vacuum, abs won't produce any refrigeration, which is another symptom you are seeing.

The design generator temperature at 90C will produce the rated cooling duty on the nameplate. As the input generator temperature drops off, so does the output cooling duty.

Do you have a Torr gauge conneted to the machine?

Have a look here (http://www.docs.hvacpartners.com/idc/groups/public/documents/techlit/16jb-5ss.pdf) for a read up on the Carrier 16jb

[Haden4ever]

Thanks for that Frank, i found the service manual online and intend to follow up on your points, it seems the CHP sets also feeding this bit of kit are offline until further notice due to a flooding incident, so hands are tied for now, still a bit confused about vaccing, the manual just says to vac to the sat temp, is it as simple as that?;)

[frank]

If you can get down to below 6 Torr and it holds then you should be able to get the machine cooling
Using just the small vac pump that you keep on the van will take forever though
Big ab machines need vac pumps built for removing larger cfm's, probably 3 phase jobbies :D

[Haden4ever]

Thanks, i'll bear that in mind, suck till it blows eh :D

[alan wolf]

Hello

An abs units solution should be checked annually for its condition as it may need inhibitors and additives for corossion protection as well as alcohol for maintaining performance. The inhibitors are normally in new solution but can 'wear' out. Not sure what spec is for Carrier solution.
The saturation tables for water will tell you what pressure should be in unit at standing temperatures, 5-6mm abs is when unit in operataion at maybe 45 deg C LWT. Non condensibles in unit will certainly prevent good operation and you need to be careful not to overheat solution and 'crystalise in heat ex.
Regards
Alan

[alan wolf]

hello
update
should be 45 deg f in my last comment

regards
aww