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Regassing the aircon

Renewable-powered transport (EVs & e-bikes)

Last Post by Majordennisbloodnok 2 months ago

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Majordennisbloodnok

(@majordennisbloodnok)

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Joined: 5 years ago

Posts: 2089

Topic starter 08/06/2026 9:09 am [#3048]

I'm not particularly expecting an answer, but I ask the question on the off-chance.

My EV is showing signs that the gas pressure in the aircon is getting low and so is struggling to cool things down properly in the hot weather. As a result, I need to get it regassed, but the problem is that it's got the optional heat pump in it and so is gassed with R744 (carbon dioxide). I'm struggling to find anywhere in the South East other than a main dealer who is equipped for this particular gas, and have wasted more than a little time with garages that say they can sort it because of the make and model before actually seeing it and realising they can't, courtesy of not listening to me initially.

Frustrating, but does anyone know of an outfit that can REALLY deal with R744, is based in the South East and doesn't charge an absolute fortune?

105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs

"Semper in excretia; sumus solum profundum variat"

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Batpred

(@batpred)

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Joined: 2 years ago

Posts: 1100

08/06/2026 9:56 am

Posted by: @majordennisbloodnok

↑

Frustrating, but does anyone know of an outfit that can REALLY deal with R744, is based in the South East and doesn't charge an absolute fortune?

Understand the frustration with a less common heat pump gas.
Seems like these may help, they appear to be based in Ilford. Unusual to market it via ebay, but may help..

Googling it suggested BOC provide co2 canisters at reasonable price but that would probably be the start of a project. 😁

8kW Solis S6-EH1P8K-L-PLUS hybrid inverter; G99: 8kW export; 16kWh Seplos Fogstar battery; Ohme Home Pro EV charger; Vaillant Arotherm Pro 7kW; 100Amp head, HA lab on mini PC

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Majordennisbloodnok

(@majordennisbloodnok)

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Joined: 5 years ago

Posts: 2089

Topic starter 08/06/2026 10:32 am

Thanks, @batpred.

To be frank, I'm not keen on trying to do it myself but I'll bear it in mind when talking with the local garages that are being as helpful as they can. There are one or two that recognise they're going to have to add R744 to their repertoire, so who knows....

"Semper in excretia; sumus solum profundum variat"

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ASHP-BOBBA

(@ashp-bobba)

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Joined: 2 years ago

Posts: 493

08/06/2026 9:02 pm

@majordennisbloodnok you need specialist C02 charging station and equipment, the main dealer should be able to do this for you if they supply the car with it.

It charges at much higher pressure than normal refrigerant and is mass critical on charging, you cannot charge by monitoring the gauges.

AAC Group Ltd covering the Kent Area for design, supply and installation of ASHP systems, service and maintenance, diagnostics and repairs.

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Majordennisbloodnok

(@majordennisbloodnok)

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Joined: 5 years ago

Posts: 2089

Topic starter 08/06/2026 9:44 pm

Posted by: @ashp-bobba

↑

@majordennisbloodnok you need specialist C02 charging station and equipment, the main dealer should be able to do this for you if they supply the car with it.

It charges at much higher pressure than normal refrigerant and is mass critical on charging, you cannot charge by monitoring the gauges.

Thanks, @ashp-bobba. That confirms me in not wanting to do it myself. Good to know.

"Semper in excretia; sumus solum profundum variat"

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