We dont have a smart meter in the shop. Is there a device that will let us measure how much energy our Aircon unit is using.
It’s hard wired so can’t use one of those plug in devices.

You can get clamp on energy meters. Cheap ones on amazon and ebay.

eg :https://www.amazon.co.uk/DollaTek-80-260V-Amperage-Voltmeter-Multimeter/dp/B092VYQ697/ref=asc_df_B092VYQ697 (Random google hit)

Not so simple unfortunately, the clamp meter would need to go over a single core to measure current (can’t just go over a twin and earth lead/flex) and the mains wiring would also need to go to the unit to measure voltage.

As goldfish24 says, you cannot use that clamp type of meter on the whole lead (live and neutral together). It could be used near your consumer unit though, where the live and neutral conductors will be separate. It will only show your total energy consumption though, like a smart meter.

Why do you want to know?
You might be better off just looking at the AC data plate for it’s current or power rating.

We need to know if it’s cheaper to chill the whole shop or just the chocolate cabinet.
It seems the whole shop is the cheaper option. Just need to know for certain.

If your still using that open fridge then highly likely the air con as it at least is sized to cool the room unlike the fridge.

Can you take readings from the ordinary meter? They usually record to 0.1kWh, and your aircon is likely to be a couple of kW, so the effect should be obvious over a few hours.

will the manuals / manufacturer not have that kind of info?

I think you’re asking an impossible job of your shop’s air conditioning.

The open chiller will be drawing about 2kW and using that energy to extract about a further 4kW from the fridge.

You’re then asking your big air conditioning unit to take that 6kW and move it outside, so at an absolute minimum it’ll be a further 3kW.

10 hours / day gives about 18,000 kWh over the year, or about £6,000 just to chill your chocolate. Plus the additional cost of fridges etc which run 24/7.

Have you tried a load of freezer blocks under the chocolate to see if it helps with the energy use?

get Plastic display models of your chocolate .

Put them in the now turned off open fridge.

Put actual chocolate in a suitable fridge with a door.

Save loads of ££££ have safe chocolate.

The cabinet has doors and uses 18kwh a day ,even if it’s not spinning it’s fan it’s using 3kwh.
Following advice from the chocolate company we won’t need to chill the chocolates til the weather gets really hot.
When we had the Aircon installed in 2010 the man said it would cost 50p a day to run.
During the winter we didn’t notice much of a spike in usage when we had the Aircon heating the shop.
I’d just like to know exactly which is cheaper to run.

During the winter we didn’t notice much of a spike in usage when we had the Aircon heating the shop.

Well, you wouldn’t with ~6kW coming out of your chiller cabinet and into the surrounding air.

The cabinet is only currently turned on for lights not cooling.

I’ve got some numbers…what do they mean?

Shop with no Aircon or Choc cabinet 6.3ish.
Shop with Aircon on reading is 7.7
Shop with Choc cabinet on.8.7

I would say that your clamp meter isn’t working properly or there’s an issue with the way you’re taking the measurement. Are the jaws definitely closed?

Is it possible that your shop has a three phase supply? At the moment those figures suggest that your AC uses about 300W and the cabinet about 500W. I actually think the cabinet figure is not unreasonable for what’s essentially a fridge with the door always open, but the AC seems low. If you only measure when the compressors aren’t running, though, you’ll get falsely low results.

That particular meter can record peak readings. I’d be tempted to leave it clipped on for 30 minutes or so to see if it records anything unusual.