My combi boiler pressure has gone down below 1bar, no C/H but hot water. How can i build up d pressure?

Vaillant Turbomax 824E. Want to refill with water and build up the pressure. Any advice please?

If i remember correctly the Turbomax combi should have a "built-in" filling link. If you look under the boiler where the pipes connect to it you should see a silver braided hose which is quite thin. On both ends of this braided hose there should be small black things which look like little levers. Turn one of these a quarter of a turn and then turn the other one the same, you should hear a rushing sound which is the central heating filling, keep your eye on the pressure gauge on the front of the boiler and when the pressure reaches between 1 and 1.5 bar you should turn both or these little levers back to their original positions (i.e. the OFF position) Your heating system has now been filled (or topped-up). You should probably bleed the radiators after doing this. Ensure you keep an eye on the pressure gauge because as you're releasing air this will cause the pressure to drop slightly. As long as the pressure in your heating system is between 1 and 1.5 bar when cold you should have no more problems.
If the pressure continues to drop after you've filled it up then it's either gonna be a leak somewhere on your heating system or maybe a faulty expansion vessel or Pressure relief valve. If this is the case then you should contact a qualified heating/gas engineer.
Hope this has helped??

there should be a filling loop a hose between the cold feed pipe and the ch heating pipe open the valve and watch the pressure go up

You should have a filling loop flexible hose which coonnects from mains water to CH Flow or Return via a non return valve. connect this and turn tap on to fill your CH up to pressure normally 1.5. You may need to bleed rads of air especially farthest away and highest one.

Open water tap to restore presure to about 2 bar. If it happens again try replacing the blow-off valve.

You should have a repressure valve on one of the pipes near the boiler. It should connect with the mains, usually by a flexi hose. Turn this tap on to repressure but don't over do it.

If you are having to top up a lot check for leaks. You'll have no CH until the system has enough pressure. It shuts down as a safety measure.

use the tap on the filling loop

Look under the boiler there should be a hose attached between two pipe's ? look to see if there is a tap, or screw driver union between the hose and the pipe? this is the filler valve for the boiler.You will have to also look for the pressure dial,fill the boiler to the recommended amount ,this information should also be in the user manual

I'm not sure if we have the same model or not but i have a valiant combi boiler. underneath the boiler there are two things you can turn. turn them 90 degrees and the pressure gauge on the boiler should go up. once the pressure is back up turn them back 90 degrees again.

There is most likely a hole some where if you can plug up the hole it will go up.

The normal pressure is one and a half bar.
As others have said their should be a stainless steel flexible pipe with a tap at one end - this is connected to your mains pressure fresh water pipe. Turn on the tap and watch the pressure rise. Pressure drops due to badly made join in pipework, join is good enough to stop water spurting out but, not good enough to prevent water vapour (a very fine gas) from escaping. So, over time pressure drops.

on my combi boiler there is a tap which you open to let in water and build up the pressure find one that shut open it see the pressure rise on the gauge and shut it back off..