Draining worcester bosch highflow 400

[eddiemacthedog]

Want to freshen up the heating system in the house, as moved in last year and unsure when it was done last.
Now its a combi, ive never drained a combi before just the normal feed and expansion, i isolated the water feed to the boiler and found two drain plugs under my side door floor mat in the house which must be for the heating and maybe the water pipework for the house, now i open them and nothing , turn the water on and one flows so that must be the water pipework, is there anything at the boiler end you have to open or fiddle with as i've never had a combi before.

thanks in advance.

 

[ServiceNumpty]

You may have some drain points under the radiators, or alternatively the drain point for the 400 is under the boiler itself near the red expasnion vessel, it is a bit of a bugger to get to.

 

[eddiemacthedog]

no drain cocks on any radiators and not an option to under with carpets, laminate etc, system is also microbore if that makes a difference i dont know.

 

[Agile]

If you isolate the heating circuits at the boiler then you can still get HW when your rads are drained.

Unless there is a problem I dont see why you would want to drain anything though!

Tony

 

[eddiemacthedog]

would just like to clean and flush the heating system as im not sure when it was done, as the hot water is fed from the combi do i have to isolate the hot water from the boiler when i get it drained and start adding chemicals or am i going off on a tangent here?

 

[Agile]

best to take a water sample first and then decide if anything needs to be done!

Tony

 

[eddiemacthedog]

Sample from a radiator you mean? What should I look for?

 

[ollski]

highflow 400 you drain the primary water from the drain tap on the pressure relief valve and the hot water from the drain cock under the pump.

 

[eddiemacthedog]

Primary water is heating water, ie radiators etc?

 

[petit_pablo]

If you isolate the heating circuits at the boiler then you can still get HW when your rads are drained.

Tony

Use WB isolation valves! Professional suicide

 

[boilerdoktor]

highflow 400 you drain the primary water from the drain tap on the pressure relief valve and the hot water from the drain cock under the pump.

the drain tap you mention is a manual air vent, the drain off is right hand side at the bottom of the slave tank behind the removeable plate