View Full Version : CO 2 regulations and codes of practice

14-07-2017, 11:28 PM
I know that the changes in using natural refrigerants has been on the agenda for a while now, but suprisingley the phasing in seems to have happened overnight. Even Fosters have started using HCs, and suprisingley CO 2 now seems to be the choice with the large plant and racks despite the Tescos disaster in Manchester some time back.

I had a call from a construction company that I used to deal with a couple of months back to assess the condition of a system in a disused supermarket that's been boarded up for almost 20 years. They wanted to know whether or not it was working or salvagable. I viisted the site and the system turned out to be a plant with parrallel compressors, which I was informed was a rack. There's also fire damage to the system from a spread of fire that had all but destroyed the control panel, and had dripped tar from the roof onto the compressors so I couldn't even see what make they were.

As I have never worked on such systems, I couldn't find out whether or not it was an ammonia, HCFC or CO 2 system, so I was reluctantant to even connect my guages just in case I was breaking any rules, and not knowing if a standard recovery machine would be suitable for ammonia or CO 2.

I informed the company that I would be back in touch when I had obtained more information about the plant and what type of medium it used. Then it would more than likely be scrapped and salvaged so the building can be dropped

After doing some research, it would seem that CO 2 can be vented into the atmosphere despite its GWP/TEWI of 1, I can't find any data on it within BSEN 375. Although I suuplemented my first 2078 refrigerant handling with ammonnia, I never have worked with it and I can't remember anything about it except its flammable and toxic.

Are there any regulations or supplememntary guidance notes that state that you have to recover CO 2, and that you can't vent it?

I know with HCs it is similar to the LPG regs and you can vent it out to an external lower point away from untrapped drains and any where else it can collect. But as CO 2 is innertly natural in the atmosphere just like Nitrogen. Is it just the general safety of its use regarding its high pressure and a well ventilated area to reduce the risk of aphyxiation that needs to be considered when venting it?

15-07-2017, 08:59 AM
I doubt if a 20yr old plant is running co2 but in any case co2 can be vented to atmosphere, Your best bet is to check the expansion valve labels of cabinets to see what gas they are on,

15-07-2017, 12:24 PM
That's what I thought, I actually think that they could be even older because the supermarket was built around the mid eighties and has been a Kwik Save, Safeway, and a few other small concerns then boarded up. I noticed that there had been a fire some years ago whilst it was empty, maybe intentionally for insurance or by vandals.

The gondolas have all been removed and the stubs capped off, they were probably scrapped or moved into another store to create floor space for storage as there ie empty shelve racking, with the stubs being capped it could be a sign that there is still some refrigerant in the system but I was too nervous to find out.

The fire damage is only on the top floor and the plant room and has never been touched since, there was probably none or indaquate insurance cover and that's why its been left so long with no attention until recently for demolition.

If I get the chance to go back I might just set up some temporary lighting and try chop away the tar and try to find some system access. I have some 410 a guages and I will see what the static pressure the system is and decide to either vent or order several yellow tops.

Regarding ammonia, although I did the 2078 at least ten years ago, I have never been involved with it since so I am totally clueless with it. If I get a whiff of it connecting my guages then I suppose I'll know if it is ammonia in there.

I've been trying to source a training provider for industrial systems for some time now, and up to now all the companies are keeping their cards close to their chest. I know that there are a few in the US, which I will probably end up going over there to absorb what they have to offer. And then do the CO 2 over here and do the ammonia again.

Because I should imagine the US licences won't be recognised out of the US, just like any other countries licencies are only recognised within their respective boundaries, although they will be on par with UK and European standards with exceptions to the guidance notes and commissioning records that are used and the way that they will be worded.

15-07-2017, 03:30 PM
It wont be ammonia anyways as it wouldnt be allowed in a public shop ,At the age your saying i would say 22 or 502 so it would have to be decanted and sent off for incineration .

15-07-2017, 04:49 PM
That's what I'm thinking, but I need to be sure that the last owners didn't upgrade to a glycol/CO 2 cascade before I commit myself to decommission it.

But now I know that CO 2 can be vented it and the likelyhood of it being ammonia, it shouldn't be a big problem.

15-07-2017, 06:50 PM
If its 20yrs boarded up ,there was no co2 in use in commercial refrigeration that far back.

15-07-2017, 07:36 PM

But I just needed to check my options before I commited myself. And with Safeways being American, and after researching I know that they were using CO 2 back in the early/mid nineties and I had to consider that before I commited myself and commited an offence.

Thank you for re assuring me and advising that CO 2 can be vented, and that ammonia can't be used within a shop having public access.

If I go back to de commission I'll keep you posted on what was in there.

15-07-2017, 08:00 PM
If it was ammonia you should recognize it by it being all steel pipe & fittings, also compressor on the end of it would also indicate something, as would be open drive, water cooled heads if recip.
If it was CO2 it would have vented anyway due to the massive pressures.
It also would be a different looking design, more reliefs everywhere etc.

15-07-2017, 09:11 PM
Thank's Ranger1, its covered in pitch from the roof and other debris. Although the compressors have the siloutte of the large semi hermetic that you would expect on racks, and the line set that's capped off that fed the gondolas looks like galve.

I asked the company that sent me if they had any planning records, fire officers report and architectural information but I haven't heard anything back as yet.

I'll update this thread if and when I get asked to go back.