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Emptying our Aira system while radiators and pipes are moved?
Hi all first time poster
We had an Aira system fitted several months back. We’ve got builders fitting a new kitchen and building a new utility so needs to empty the system in order to do so. I cannot find any details in the manual provided at all and it’s the first time they’ve worked with an air source system. I have mailed Aira asking them to provide details but wondered if it was something you guys could advise on?
If you are to be draining the primary system then watch out if you have a glycol mix as the fluid. Not only is it messy stuff it is expensive...too expensive to dump out via the drain. It is better recovered and re injected when the system is refilled. You might need a heating engineer with the correct kit.
Posted by: @abernyteNot only is it messy stuff it is expensive...too expensive to dump out via the drain.
It's also extremely toxic and very bad for the environment, so there's a lot of reasons of recapture and reutilise.
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Posted by: @editoralso extremely toxic
If it's for domestic heating systems it's not toxic at all. It's not the same as car antifreeze.
The chemist used in a domestic heat system is Food Grade Inhibited Propylene Glycol.
@johnmo I’m not a glycol expert, but I know that when it comes to glycol used in heat pump systems, the two most common types are propylene glycol and ethylene glycol.
The key difference between propylene glycol and ethylene glycol lies in their toxicity and performance. Propylene glycol is less toxic but has a higher viscosity than ethylene glycol, which means it doesn’t transfer heat quite as efficiently, particularly at lower temperatures. Despite this, propylene glycol is favoured in many cases due to its environmental and safety advantages, but it still has additives and should be disposed of properly.
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How Installing a Heating System Became a National Nervous Breakdown
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Rewritten and updated for 2027
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Thanks guys spoke to the engineer from Aira and am all sorted. No glycol in the system and he’s happy for my heating engineer to call him tomorrow. Great service from them.
@smedley_odwin I think it’s great your system is glycol free, but I am a bit surprised because most large installers just do it by default. Do you know if you have antifreeze valves installed?
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Free UK shipping.
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
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