Indy Total Construction

One of the great deterrents to anyone wanting to remove a radiator is the prospect of having to drain the whole system. However, this won’t be necessary provided the radiator to be replaced has a valve at both the hot water inlet and the outlet. Once these are closed. you’ll be able to keep virtually all the system’s water isolated in other parts.

At the inlet end you’re likely to find the hand-valve which is the control by which you open and close the radiator. At the outlet end you’ll find what is termed the lock-shield – valve. When you come to inspect your radiator, don’t worry if their positions are reversed — they will still be equally effective.

The first thing to do when removing a radiator is to close these valves. The hand-valve is straightforward, but you’ll have to remove the cover to get at the lock-shield valve. You’ll be able to close this valve using a spanner or an adjustable wrench with which to grip its spindle.

As you turn it, it’s a good idea to note carefully how many turns it takes to close. And you’ll find this task slightly easier if you mark the turning nut with a piece of chalk before you begin. The reason for all this is to maintain the balance of the system. After it was first installed, your system would have been balanced.

The lock-shield valves of all the radiators were adjusted to give an equal level of water through-flow so that they were all heating up equally. So, by noting the number of turns taken to close the lock-shield, when you come to fit the new radiator you can simply open it up by the same amount — so avoiding the somewhat tedious task of rebalancing the whole system.

Once you’ve closed both valves. you can unscrew the nuts which connect the valves to the radiator inlet and outlet. Do these one at a time after having placed a low dish under each end to collect the water and protect the floor.

Use an adjustable wrench to undo the coupling nuts. It’s wise to hold the circulating pipe securely in place with another wrench. Otherwise, if you apply too much pressure to the coupling nut you risk fracturing the flowpipe, and this would cause you a lot of extra work and expense as well as causing quite a mess.

It’s a good idea to get the radiator out of your home as soon as possible-just in case it leaks any remaining dirty water on to your carpet.

Internal corrosion in modern radiators arises from an electrolytic reaction between steel of the radiators and the copper circulating pipes of the central heating system. This results in the production of a corrosive black iron oxide sludge (magnetite) and hydrogen gas.

In a similar fashion, if the original installation of your heating system was somewhat messily done, then copper swarf, produced when the pipes were cut, could have been retained within the circulating pipes.

This will also corrode the steel at any point where the two come in contact — usually within a radiator. Because the raw material from which the sludge is produced is the metal of the radiators, eventually they will leak and need to be replaced. And as the sludge is also attracted by the magnetic field of the circulating pump, its abrasive qualities are a common cause of early pump failure.

Early indications of serious internal corrosion are a need to vent one or more radiators at regular intervals, and cold spots on their surfaces. If in doubt, the diagnosis can be confirmed by applying a flame to the escaping gas when the radiator is being vented. If it burns with a blue and yellow flame, you can be sure that hydrogen is in the system and will have been produced by the chemical reaction of the two metals.

Once you’ve confirmed that corrosion is present within the system, you’ll have to flush it through and introduce a reliable corrosion preventative chemical into the feed and expansion tank. By doing this, you should be able to prevent further corrosion and so save your system.

Homes are heated by one of three methods:

• Hot water

• Steam

• Warm air

Hot water systems use a pump to circulate hot water from a boiler to all the rooms in a house. Keep the radiators clean and the tops uncovered so that heat can circulate. About once a year, drain the boiler and expansion tank. Turn off the burner and the water coming into the tank.

The process is the same as flushing a hot water tank. Attach a hose to the drain and open the vents on the highest radiators to let in air. After the water runs clear, close the drain and open the water supply. Relight the burner. When you hear water entering the radiators, close the vents again.

Refilling the tank will let air in. As the air rises it becomes trapped in the radiator and keeps the water from circulating. You will have to “bleed” each radiator. This is done by opening the radiator to let out the air. As soon as water comes out, close the radiator. Be careful when catching the water. It will be hot.

A hot water system is controlled by a thermostat. The thermostat controls an electric pump which circulates water throughout the house.

Bleed the radiator of trapped air by opening the knob until water just begins to trickle out. Be careful: the water will be hot.

A steam system is similar to the hot water system. It does not have a pump though, because the steam circulates freely. Noises occur when water becomes trapped in pipes that do not slope back toward the boiler. This may be cured with a block of wood under one leg of the radiator. Knocking may also occur if the steam valve is not fully open or closed.

Loose packing in a valve is often responsible for steam leaking. This can be repaired just as you would a faucet. Turning down the packing nut may stop the leak. If not, repack the stem.

Basically a warm air furnace heats air which is circulated by a blower. Warm air systems may be electric, gas, or fuel oil heated. Heated air travels through ducts and out through grills or registers in various rooms. As with the other systems, a warm-air system must be kept clean. Clean or change the filters monthly when the heater is in use. Change them at least once a year. Also clean the fan blades and vacuum around the registers. If necessary, tighten the belt.

The motors in all systems need oiling. Use a lightweight motor oil and fill the cups or filling tubes in the motor. Fans and water pump bearings need oiling as well. If pipes or ducts run through cold areas, they should be insulated.

Central air conditioning may operate through the heating ducts. However, many homes have individual room air conditioners. The main thing is to keep the filters clean when the air conditioner is in use.

To stop radiator pounding make sure the pipes are level so water is not trapped. Also try adjusting the valve.

Make repairs with the furnace off and the boiler cold. If steam leaks out the radiator valve, tighten the packing nut. If that doesn’t work, remove the packing nut and repack the stem with packing cord. Reassemble the valve.

A warm air heating system heats air and blows it through heating ducts. The air can be heated by oil or gas burners.