Working on vaillant 828 boiler

[Richaj]

To change the diverter valve, can I drain just the boiler and not the whole CH sytem?

 

[gaspro1981]

turn the iso valves off under the boiler and hey presto no need to drain the whole system

 

[Richaj]

turn the iso valves off under the boiler and hey presto no need to drain the whole system

I've identified in the boiler spec. the "CH flow service valve" on the left underneath the boiler. Is this the one to turn off?

 

[simond]

You'll need the CH return valve as well. Or a set of wellies.

 

[Richaj]

You'll need the CH return valve as well. Or a set of wellies.

Thanks to both of you. I think I've got it now, I was getting confused with the valves on the filling loop. Just to confirm then, I need the two in-line valves on the 22mm pipes at either side of the boiler. OK?