Supermarket gas leaks

[bowral fridgy]

Any one had any experience fitting refrigerant leak sensors into open front multi-decks, wide-island & glass-door freezer cases, glass-front deli cabinets, walk-in medium & low temp cold rooms etc. I'm finding that when a particular rack system springs a leak that by the time the loss is large enough to trigger a high temp alarm, someone at the store or security monitoring centre notices and places a call, you finish the job you're on & get to site, suss out problem and locate the leak, you have generally lost 100 kg or more of 404A. There has to be a better way of detecting leaks early or small leaks before they become big ones. Any ideas ?

[hillbillywillie]

Hi Bowral, here in the US big stores like Target have IRLDS leak detection systems. They place small filters around the store in various places which sample the air and set off an alarm when so many parts per million are detected.
They don't typically fit them in cases, but divide the store into zones.
Each cooler and freezer has one or two usually mounted near the evap coils.
They are goo, but make working in the motor room a nuisance, as the alarm is usually set off when changing liquid line driers or doing pipe work, then the siren goes off, and a huge flashing strobe light comes on, then the monitoring company sends a call to our company if you don't let them know quick enough!

[hillbillywillie]

btw, how's Australia? I have relatives out there somewhere. They lived in the house on the hill you can see in the programme "Skippy". Sadly, we lost contact some time ago.

[WINJA]

btw, how's Australia? I have relatives out there somewhere. They lived in the house on the hill you can see in the programme "Skippy". Sadly, we lost contact some time ago.
Thats brilliant , hey your from the USA do you know my cousin Robert? he lives there now

[nike123]

Ignore, something is wrong !

[nike123]

Thats brilliant , hey your from the USA do you know my cousin Robert? he lives there now


Yep, that is how we speak here with someone in diaspora. :D

[bowral fridgy]

Thanks HillBilly Will for suggestion on IRLDS. Most stores have 1 or 2 leak sensors (not sure what type) located at ceiling level but wouldn't refrigerant vapour especially cool temperature tend to pool at floor level ? Recently had a ruptured hose on header spraying out a fine stream of liquid and the sensor under that particular rack not registering anything. The plant-room exhaust fan may have been drawing the vapour straight up & out though. You say that you have seen sensors fitted near the evap coils in some cases. How does the low temperatures affect the sensitivity & reliability ?

[bowral fridgy]

HillBilly Will regarding your cousin in Australa. Some years back had some relatives from UK visiting and wanted to pat the koalas or something Anyway ended up at Waratah Park - The Home of Skippy! The ranger station is still exactly the same. Couldn't see Skippy though - guess it was his day off. If you give me your cousins name and I'm there again I'll coee and see if he answers. Regards

[flyinkiwi]

LOL... Beware of fitting leak detectors in butchery prep areas...

Seems to be a corrosion issue with the chemicals used to sanitise the walls and floors, resulting in persistent false alarms.

Has anyone considered / used the sightglass bubble detector for refrigerant charge monitoring?

[flyinkiwi]

Haha. There is one other way to detect small leaks before it causes a problem... PPM.

Or do what store owners/jaded fridgies/frustrated service foremen usually do: Bury your head in the sand. Maybe you'll smell it coming from underground.

Just the general experience of supermarket refrigeration - store owner acts like "Stop wasting time looking for a leak and get the hell out of my store - your time is costing me."

[psycho]

sort off the same topic...i've found that propeiretry(cant spell that)bubble type leak detectors from a bona fido fridge wholsaler sets me gas sniffer off into a frenzy,hold it over the top off a bottle off the stuff and put your fingers in your ears,not a butcher in site,makes no difference.
thought that skippy was a dolphin??

[750 Valve]

Thanks HillBilly Will for suggestion on IRLDS. Most stores have 1 or 2 leak sensors (not sure what type) located at ceiling level but wouldn't refrigerant vapour especially cool temperature tend to pool at floor level ? Recently had a ruptured hose on header spraying out a fine stream of liquid and the sensor under that particular rack not registering anything. The plant-room exhaust fan may have been drawing the vapour straight up & out though. You say that you have seen sensors fitted near the evap coils in some cases. How does the low temperatures affect the sensitivity & reliability ?

Bowral Fridgy in a perfect world they would be positioned at ground level and every second or third case so as to sense leaks early, fact is though that they are expensive and the supermarkets here are only fitting them to comply with legislation, and as a matter of safety (asphyxiant in high concentrations, etc) to save staff and customers.

Coles specify 3 sniffers, 2 in plantrm - 1 high and 1 low level, so typically they are mounted on the back of swbds where the ducts exit with data cable, easy to install, they also specify 1 on the shopfloor, they do not specify its location so it usually ends up on a bulkhead close to the plantroom, once again ease of installation and less wiring.

WW specify 3 sensors also 1 A/C supply air, 1 A/C return air and 1 plantroom, the ones in A/C air stream are usually near by/adjacent return air gille and supply air register.

The contractors only do what is asked of them and its such a cut throat section of the industry that the contractors are not going to go out of their way to spend additional money to go above and beyond the customers specs. In some instances we have been asked to remove equipment installed above and beyond their specs (like ball valves on condensers)

IGA is a whole different kettle of fish so if you are talking Moss Vale store then that is a mix of an old WW spec whatever the owner specified.

IRLDS are the way to go but the cost is significantly more than the standard CPC, Danfoss and Presscon gas sensors. The Co2 stores use IRLDS in the coolrooms for safety but they are currently the only ones using infra red and thats because they have to.

Hope you find your gas leak mate

[bowral fridgy]

Thanks 750 Valve for detailed answer We sure dont live in perfect world so have to do the best we can. All the reports I read estimate that the average supermarket loses around 16% of its total gas charge every year but what store wants to pay you to check every brazed joint, valve, evap & cond coil etc for leaks on a regular basis? I understand that when our carbon emission trading scheme is implemented the price of fluorocarbon refrigerants will increase and for high GWP 404A it may treble or quadruple even. This may make PPM more appealing. I guess we will all welcome the day when transcritical CO2 is the norm. Regards

[smilies]

All the reports I read estimate that the average supermarket loses around 16% of its total gas charge every year but what store wants to pay you to check every brazed joint, valve, evap & cond coil etc for leaks on a regular basis?

When the contractor has a full maintenance contract and is supplying the refrigerant. :eek::eek:

[nike123]

When the contractor has a full maintenance contract and is supplying the refrigerant. :eek::eek:

:off topic:
Hi smilies!
Are you having problem with your vision?
If yes, you could enlarge (or reduce) all letters by pressing Ctrl button on your keyboard and simultaneously roll mouse wheel.

[smilies]

:off topic:
Hi smilies!
Are you having problem with your vision?
If yes, you could enlarge (or reduce) all letters by pressing Ctrl button on your keyboard and simultaneously roll mouse wheel.
No, but thanks for the concern. I like the 'Georgia' font, it's pleasing to my eyes.
And I make it large because what I have to say is very important , nobody listens to me at home or work, so somebody better at least read what I type here :(:(

[smilies]

:off topic:
Hi smilies!
Are you having problem with your vision?
If yes, you could enlarge (or reduce) all letters by pressing Ctrl button on your keyboard and simultaneously roll mouse wheel.

Also, I couldn't get your tip to work for me, maybe because I have Vista? What I did was set my computer for all text to be a little larger.