Honeywell EA122-AB Automatic Air Vent with Adaptor

I have an unvented heating system which has complex pipe runs due to the age of the house. So, I need quite a few venting points. I have tried various automatic air vents and they either leak under the 1.5 bar pressure of the system, or get blocked and don't vent. These just work and I won't buy another brand now. Feature one: twist the body and it seals off the bottle so you can maintain it (never needed to do this in 5 years of using them). Feature two: the vent cap has an expanding fibre washer which closes on contact with water and so, in the unlikely event of a leak, you won't have a soggy ceiling...Top rate piece of kit.

If you have air in your system DO NOT BUY THESE UNITS THEY ARE USELESS!!!!! I had bought 6 of these and not one worked. Buy the £13 brass ones which work faultless. These Honeywell ones have to small a float fitted that don't allow the vent to open under pressure of 3 bar. Avoid at all costs!!!!

This is some generic (German made) part - time will tell if it is any good; it is NOT a like for like (brand). replacement.

Does what it says

I'm a DIYer and was have problems getting my heating back on after I replaced the radiators. This once installed bled out the air and worked easily. The only down side is its a strange size. So you may need to find an adapter