Are deaerators a necessity with combi boiler?

[dilalio]

Deareator , made my rads quieter my combi system. Used to hear occasional pebble sound in rads. With regards to corrosion it will remove some dissolved from the first fill but nothing more for it to do,

H2o contains oxygen and this can constantly be released from the liquid through all sorts of processes.

 

[^woody^]

I was about to get a filter fitted (Fernox Omega TF1) to my trusty Ideal Isar combi (no giggling at the back please), and have come across the Spirovent - which may well help with some recent flow noise through my radiators. The whole system and boiler is probably around 18 years old.

Would I be better off fitting something like the SpiroCombi - if so on flow or return, or would a separate deaerator and filter be better?

Thanks

 

[Mottie]

I have an Omega TF1 on my return and a Spirovent on my flow. Works fine for me.

 

[Rico_Trudeau]

With regards to deareator's doing nothing after the first fill. It's a bit like saying a Smoke alarm is doing nothing, until it is. Yes a deaerator has less to do after the first fill and first few circulation cycles but it's maintaining what it's already done. The majority of micro air bubbles are formed just after the boiler pump and heat exchanger. Removing the majority of dissolved air/gas from the most important component of your heating system (THE WATER) will do two main things 1. Make your heating system more efficient. 2. Will reduce to a minimum corrosion and in a well maintained system almost completely eliminate it. If you install a deareator into a new system it will be your Magnetic filter that is basically doing nothing which is why you should make sure you have a filter that catches all debris and not just magnetic. Every year I introduce a bit of fresh water into my system when cleaning my magnetic filter (as it's the type that cleans the filter by flushing it out (Fernox TF1) ) and I check with some soapy water if the deareator is still working and yes it kicks into life again and removes the tiny bit of gas introduced in the new water. After the third year my magnetic filter was spotless and remains so. I also recommend putting an auto bleed valve on your highest Rad which is normally a towel rail rad in the bathroom you don't really need any others and you'll have a system that simply doesn't corrode. As others have also said a deareator and Auto Air Vent are two different things. They are not the same so don't get them confused.

 

[Johntheo5]

This is a old thread.

I have rarely if ever heard of deaerators installed on sealed domestic systems.