A slight pressure drop over time in a boiler system is not uncommon, and it may be caused by various factors such as air in the system or minor leaks. It's important to keep an eye on the pressure and bleed the radiators as needed to maintain the proper pressure.
However, if you are noticing frequent pressure drops and needing to bleed the radiators often, this could be an indication of a more significant problem such as a leak in the system. In this case, it would be best to have a professional technician come and check the system for leaks.
From an economic standpoint, it may be more cost-effective in the long run to address any potential leaks now rather than waiting for them to worsen and cause more damage to the system. The cost of a technician's visit to check for leaks would be much less than the cost of repairs or replacement of a damaged boiler.
As a DIY homeowner, you can also try to locate the leak yourself by checking the joints and connections of the system, and looking for any visible signs of leaks such as water stains or drips. If you do find a leak, it is best to call a professional to repair it.
It's worth noting that the fact that the central heating pipework in your house is at least 40 years old, it's possible that some of the joints and pipes may have become corroded over time and may need to be replaced.
To better understand and troubleshoot the issue with your Worcester-Bosch Greenstar 30CDi boiler losing pressure, you can consider the following steps:
- Check the pressure gauge on the boiler: Make sure that the pressure gauge is reading within the normal range, usually between 1-1.5 bar. If the pressure is below the normal range, you'll need to add water to the system to bring it back to the normal range.
- Bleed the radiators: If you hear gurgling noises or if one or more radiators are not getting hot, you'll need to bleed the radiators to let out any trapped air.
- Check the expansion vessel: The expansion vessel is responsible for maintaining the proper pressure in the system. If the pressure in the expansion vessel is too low, this could be the cause of the pressure drop.
- Check for leaks: Look for visible signs of leaks such as water stains or drips around the boiler or around the radiators. If you suspect a leak, it's best to call a professional technician to fix it.
- Check the system's valves: The valves in your heating system may not be functioning properly, which can cause pressure drops. Check the valves and make sure they are open and working properly.
- Check the pump: The pump is responsible for circulating hot water through the system. If the pump is not working properly, this can cause pressure drops.
By following these steps, you can get a better understanding of the issue and determine if it's something you can fix yourself or if you need to call a professional technician. It's important to keep in mind that working on a central heating system can be dangerous and if you're not comfortable with handling it yourself, it's best to consult a professional to avoid any potential damage or injury.