I have no hot water coming from my pessurised(?) system. I have cold water at full pressure at every outlet in the house. I have been told it is probably a frozen pipe in the wall and that we need to 'break into walls' to sort it out. If I am willing to live without hot water until the weather turns, is it likely to cure itself? If so, how do I recharge the pressure in the system (assuming I need to do this manually) once I have mains supply back?
When you say no hot water, do you mean that there is nothing at all coming out of the hot taps or that the water is cold? If it's no water at all, your information about a frozen pipe may well be correct. However, since your cold water outlets are all OK, the pressurised hot water system must have a different mains feed to the rest of the cold outlets. If cold water is coming from your hot taps there may be an airlock in the heating coil in your hot water cylinder.
Just noticed that you put a question mark after "pressurised". Do you have any cold water tanks in the loft? If so is it or are they full? I am asking these questions because I had a recurring problem two years ago after I had a pressure vessel fitted to my CH system which kept losing pressure causing the coil in my cylinder to airlock so that I only got cold water from my hot taps.
To answer your question about whether the problem will cure itself when the weather turns, it may well do if it is simply a frozen pipe and nothing else has changed. If the problem is that cold water comes from your hot taps it probably won't correct itself. May be able to offer more help if you can give more information about the system and the actual problem.
DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!