View Full Version : Blowing down a compressor into a relief stack

01-11-2013, 01:38 AM
I have seen many ammonia systems that have 1/4" lines that are hard piped from the compressor into the relief stack in order to blow down the compressor. I cannot find any information telling me whether this is legal or not in Canada. Does anybody have literature?

01-11-2013, 07:58 AM
with R22 still on the scene in abundance

cant see the Canadian Reg Setters saying anything about a little Ammonia

R's chillerman

01-11-2013, 09:22 AM
FYI our company policy is never to vent ammonia into air or water, unless water is disposed of correctly.
This applies to anywhere in Australia no mater where.

Water can be neutralized or sent to manufacturer of the ammonia for disposal.

We are told to use our transfer pump for working on compressor packages.

We also do not do as we are told!

Depending where relief stack goes i think its unlikely you can vent it. If wind etc etc blows it around, from my experience its always end up in the most unlikely places.
Then someone reports it & all hell breaks loose, not worth it.
Same when using a vac pump, probably vent it in water, then dispose of water.
We use bulk bins on sites then ship it to manufacturer of ammonia $$$$

Run a hose or something to a low stage machine (if you have one) to blow it down.
Most can be vented to its own suction first.

Interesting if someone has answer.

05-11-2013, 07:12 AM
Hi Ranger

What are you using as your transfer pump and how effective is it ?

Other parts of the plant are good options for shifting liquid around but ultimately you still have to deal with a bit of liquid and vapor which usually ends up in a big tank of water. I have diluted this water and then evaporated it or had it taken away but this has not been with out its issues.


05-11-2013, 07:59 AM
We have made a transfer pump from a large car/truck air con compressor. Don't know model off the top of my head.
Made a base with belt drive & single phase motor. Works ok, still heavy though.
Compressors cheap, maybe $300.
I think clients should be pushed to install there own, in plant room at least. Bock have small ammonia compressors for $2-3000.

23-11-2013, 10:20 PM
I think clients should be pushed to install there own, in plant room at least. Bock have small ammonia compressors for $2-3000.

Should be law when the charge is over a certain amount say 500kg for a plant to have a pumpout compressor I reckon. Our portable pump out compressor weighs 132kg so the less places I have to lug it the better!

I have never seen blow down lines connected to a PRV vent line or stack and I would say it is not a good idea.