To drain or not to drain

[Chaang]

I have a combi-boiler.

I want to swap my radiator for a towel radiator, do I drain the system down or believe that the vacuum will keep the water in?

 

[twgas]

I would say it depends on the system and what exactly needs to be done, and how confident you are

 

[Plumber90]

If you have a wet vac I wouldn't drain.

 

[Chaang]

Don't have a wet vac.

Not very confident, first attempt at plumbing.

Towel rail is shorter than rad, so wil be extending pipe and adding new angle with push-fit, then using compression onto the bottom of the radiator tails.

 

[picasso]

If your towel rad is upstairs drain the system down to just under the level of the rad your taking off, combi systems are normally easy to fill as the water is mains pressure.

 

[Chaang]

It's a bungalow.

Yes, just turn a tap on the boiler and it fills.

I'm pretty sure I'm going to drain, seems simple enough to do and refill. It's just that I have been told by several people that I don't need to, so wanted to check.

 

[Grenage]

Remember to put some inhibitor in while you're refilling.

 

[dcawkwell]

Just drain the whole system.
No issue.