There are plenty of things that can go wrong with boilers. In many cases, they can be repaired, but in some instances a new boiler installation will be the only practical way of getting a home's central heating system back up and running. Nonetheless, a boiler inspection for an eventual installation can be required for many reasons. The most usual ones are:
A boiler can lose pressure for a few different reasons, but the most usual one is that there is a leak in the system. Some boilers need a few simple steps to be undertaken to re-pressurise them, but leaks must be repaired for pressure loss not to continue. If that cannot be done, then a new boiler installation should be considered.
Some boilers seem to be working fine but make strange noises when they are in use. This is often referred to in the industry as 'kettling'. The commonest reason for these noises is that limescale has built up in the boiler or has been transferred to it from the central heating system's pipe. This problem is often found in areas with hard water.
Boilers That Switch Themselves Off
Some boilers just don't come on when you expect them to and need to be reset manually. To overcome this problem, a qualified engineer should check for low water pressure or a problem with the thermostat being able to communicate with the boiler. Other causes might be a lack of water flow or because the system's pump is failing to circulate the water in the central heating pipes correctly.
Pilot Lights Extinguishing
A pilot light could be simply blown out from a draught or because a faulty thermocouple is preventing the gas supply from entering the boiler. Either way, it should be checked by a Gas Safe engineer.