Radiators can throw up a number of problems in the domestic environment. A number of which manifest themselves with either one or a number of radiators not heating up or even only part of the radiator heating up. The root cause is sometimes the boiler rather than the radiator itself. It is possible that the boiler pump is not working or is set incorrectly, so the boiler appears to be operating normally but the radiators are not heating properly.
Other problems relate to the radiator itself. If radiators in one part of the house are not warming up, it may be it may be that the thermostat or valve on those radiators or heating zone are either not set correctly or are malfunctioning. The valve may need replacing, but it could also be a faulty electrical connection, so it is worth checking this out first.
If it is only a single radiator that is not getting warm, then it is likely to be a problem on that specific radiator such as the inlet valve, the thermostatic valve or possibly some sort of blockage in the inlet pipe. It is advisable to check the valve is set correctly first, however if this has no effect it may have to be replaced.
One of the most common problems with radiators is that sometimes you will find that the radiator may be warm at the bottom but refuses to heat up at the top.
This is generally caused by an airlock at the top of the radiator. Air can build up through corrosion, but this can be simply resolved by bleeding the radiator with a special key to release any trapped air. A little water may escape with the trapped air, so you need to be ready to catch this. If the cool area is in the middle of the radiator, but the top and ends have heated up; it could be that there is some corrosion within the radiator which is preventing the hot water from circulating.
In this case the radiator will need to be removed, flushed out and then replaced or put back as necessary. If you are concerned about removing radiators then our engineers at local plumbers near me are only a phone call away and will be happy to carry out a full radiator inspection and service. If a number of radiators have air locks, there could be a mild corrosion problem within the system – in which case it would be beneficial to flush the system through to remove any rust or sludge.
Perhaps more concerning are problems which result in water leaking from the central heating system. These issues may be simpler than they first appear, such as loose connections between pipes and valves at the radiator connections.
Joints may simply need tightening or in some cases you may need to isolate the radiator from the rest of the system and resolder the joints. Older radiators sometimes leak along the bottom seam due to internal corrosion, in which case the radiator will need replacing completely (with one of the same capacity) and probably the fittings as well. More usually there may be a hole in a pipe leading to the radiator which will need repairing with sealant, or in some cases a pipe may need replacing. It will be necessary to drain the system before undertaking this repair.