Fitting a radiator
Fitting a radiator to an existing central heating system is a relatively straight forward job that a competent DIY enthusiast should be able to do in a single day.
You first need to decide where your new radiator will be positioned - radiators are often positioned beneath windows so that the warm air from the radiator meets the cold air from the window and is circulated around the room.
Once you have chosen the location, you will need to locate any nearby central heating pipes. You can do this by lifting the floorboards, or else finding a radiator that is near by.
Central heating systems usually have two pipes, flow and return - the flow pipe brings the heated water from the boiler to the radiators, while the return pipe carries the water back to the boiler to be heated once again.
In an older house you may find a system with only one pipe, which is both the flow and return.
If you are lucky you will find a large central heating pipe attached to a manifold which has several smaller diameter pipes - this makes fitting your new radiator much easier.
Before you fit your new radiator, you will need to attach the radiator tails - these are the screw in fittings that normally come with the lockshield or thermostatic radiator valves. Wrap PTFE tape around the thread before screwing it into the radiator, then tighten with a radiator spanner or normal spanner of the correct size.
You are now ready to fit your new radiator to the wall. The initial steps are as follows:
- Measure the gap between the two fastening points on the reverse of the radiator, then draw a straight vertical line on the wall using a spirit level.
- Draw another line the correct distance apart.
- Fasten the brackets to the wall using appropriate fasteners.
- Lift the radiator onto the brackets - make sure it's in the right place!
The next step is to draining your central heating system. First, switch the central heating off. Then locate the drain off valve - if you are lucky it will have an external location, if not you will need a length of hosepipe sufficient to reach outside.
Securely attach one side of the hose to the drain off valve using a jubilee clip, and extend the other end to the drain outside - it needs to be as straight as possible, with no kinks.
If your system never needs topping up manually, you will have to isolate the water feeding the central heating system - do this by either turning off the main water supply to the property, or finding the header tank and isolating the supply to it.
Using an adjustable spanner, open the square on the drain off valve - water should now flow out of the hosepipe. Once it appears to be empty, double check by opening a bleed valve on an upstairs radiator - no water should come out. Don't cut any pipes until you are sure the system has drained completely.
You are now ready to cut into the pipe you are going to take a branch from. Use a pipe slice for copper pipes, plastic pipe cutters for plastic. There will be a small amount of residual water in the system, so place a small bowl under the pipe you are cutting to catch the water.
As you are inserting a "T" fitting you will need to cut a little more from one of the pipes to allow room. Push-fit fittings or compression fittings will be required as solder fittings will not work due to the water. If you are working with copper pipes you will possibly need a pipe bender or pipe bending spring.
Once you have inserted the "T" fitting, run the pipe from both the flow and return pipes to the new radiator - the flow pipe should have the thermostatic valve on or the lockshield with the open/close function. The return valve will have a cap on that will neither open or close the valve as it spins freely.
Connect the new radiator to new the flow and return pipes, ensuring that pipe inserts are used. If you are using compression valves, be sure that the olives are made of copper - brass olives are too hard for some plastic pipe.
Once your radiator is connected, close the drain off valve with an adjustable spanner, and remove the hosepipe. Be sure you have closed the bleed valve you opened earlier, then slowly refill the system.
As the system fills, check your new fittings carefully for leaks - if you find a leak, either tighten the nuts or ensure that push-fit the pipes are pushed all the way into the fitting.
Once the system appears to be full, you will need to bleed all the radiators to release any air in the system.