Vaillant comby pressure top up

[DIYspanner]

I believe its a Turbo Max.

Are the two valves in the picture the two to open to add pressure?

 

[Mottie]

I don't think so. Do you have a braided hose anywehere?

 

[ianmcd]

Yes that is them, use a large flat blade screwdriver, someone has been using a small screwdiver and has chewed them

 

[Mottie]

I stand corrected.

 

[Deleted member 267285]

I stand corrected.

Some boilers have an integral filling loop, this is one of those.

 

[DIYspanner]

Thanks!

So if they are the valves to open, do I open the RHS or LHS first?

Also, can I add 0.5L of anti-corrosion to the CH through one of the radiator plugs?

 

[Deleted member 267285]

Doesn’t matter which first, one doesn’t work without the other. Yes you can add inhibitor, but for a diy job might be best with a rapid dose style one, and do this before topping up the pressure.

 

[DIYspanner]

Thanks!

I checked all bleed taps were shut then topped upto 1 bar so I can use the boiler for HW.

The valves screw heads also seem to be 5.5mm hex so could use a socket.

If I were to drain the CH in the future, would that be done at the boiler or a radiator?

 

[DIYspanner]

I found this video on how to drain the CH.

 

[Mottie]

That's just how to drain the boiler, not the system. If you want to drain the system you will need to find the lowest point on your system and drain it from there but you'll have to open up a bleed valve in the highest point in the system to let air in after you have opened the drain cock. You should have a drain off valve around the lowest point.

It might look something like these:

 

[DIYspanner]

That's just how to drain the boiler, not the system. If you want to drain the system you will need to find the lowest point on your system and drain it from there but you'll have to open up a bleed valve in the highest point in the system to let air in after you have opened the drain cock. You should have a drain off valve around the lowest point.

It might look something like these:

View attachment 268416 View attachment 268417

What you say makes sense, draining the CH from the lowest point to get all the old water out.

 

[The831Bunny]

Use a brass radiator key in future to operate the filling valves on the boiler. The slot is purely there to indicate the valve position. Most people use a screwdriver, then they get chewed up.

 

[DIYspanner]

Use a brass radiator key in future to operate the filling valves on the boiler. The slot is purely there to indicate the valve position. Most people use a screwdriver, then they get chewed up.

Noted, thanks!