Draining worcester bosch highflow 400 combi

[eddiemacthedog]

Ok, need help understanding my system after trawling net to find answers, im upgrading the en-suite and replacing radiator for a towel rail, hence the need to drain system.

Firstly cannot find a draincock anywhere, system is microbore also if that makes a difference.

There is a draincock in thr boiler under the tank thing which according to the manual is primary water (whats primary water?)

Is it as simple as using one of the radiator lines?

Im on here hoping someone can point me in the right direction.

Also do i need to isolate the water to the boiler during this time or is water seperate to heating?

Soz for all the questions.

Cheers
Eddie

 

[dcawkwell]

You will have a drain valve on the central heating pipes in the house somewhere (maybe some you will never find as they
are under the floor somewhere) near a radiator perhaps. Attach to a hose pipe and open up.

There will be a drain valve on the boiler open that as well.

 

[eddiemacthedog]

You will have a drain valve on the central heating pipes in the house somewhere (maybe some you will never find as they
are under the floor somewhere) near a radiator perhaps. Attach to a hose pipe and open up.

There will be a drain valve on the boiler open that as well.

So, is the primary water drain the one i need, its off the bottom of the tank in the boiler?

 

[dcawkwell]

Drain it and see you won't do any harm.

 

[sooey]

You will have a drain valve on the central heating pipes in the house somewhere (maybe some you will never find as they
are under the floor somewhere) near a radiator perhaps. Attach to a hose pipe and open up.

There will be a drain valve on the boiler open that as well.

So, is the primary water drain the one i need, its off the bottom of the tank in the boiler?

Yes that is the drain off for the boiler, which will also drain your system as long as you don't isolate the boiler. In fact, touch those isolation valves at your peril, because they'll most likely leak if you do.

 

[eddiemacthedog]

So, could i use a radiator to drain the system down also ad the boier one is fiddly to get at?

Thanks

 

[Philnails]

Yes try not to go near the isolation valves in the boiler. I did and one leaked, not too badly though but had me worried. Stopped on its own after a while. I isolated the CH system at the boiler so I would still have hot water but the pressure leaked anyway and I had to refill the system early. Luckily I only had a rad off for decorating so it wasn't a big deal. I drained my system from the valve below one of the ground floor rads with a hoes pipe out to sewer. If i was doing it again i would just drain the CH in the morning and try and get the work done in a day so you don't have to isolate the boiler valves. Just make sure you have your CH inhibitor and filling system ready to go, I got a kit from screwfix which worked a treat. The boiler does work with CH valves isolated, just have to keep an eye on pressure. Hope this helps someone

 

[Agile]

If rad upstairs and boiler downstairs then only drain what will come out of the rad pipes toy are dealing with.

Tony