FREQUENTLY ASKED QUESTIONS (FAQs)

What does the dial on the boiler do?

The dial on the front of the boiler is a temperature thermostat. Once you turn it beyond the quarter position turning it up more will make the radiators hotter. Turn it too low and not only will the radiators become cooler, but also the hot water will not be hot enough. It was once said that if the boiler was run too cool it would create condensation in the flueways.  Advice on exactly where to set the thermostat is on our page setting up your system.

Should I leave the heating on all day?

Yes you can, it will cost no more. Many of our customers have told us that it costs no more to keep the heating on all day rather than turn it on and off. The fabric of the home gets warm and takes less heat to warm up.

Does gas escape when the pilot goes out?

No, not normally. There are fail-safe mechanisms that prevent gas from escaping when the pilot goes out. If you smell gas, turn off the supply at the meter and call TRANSCO 0800 111 999.

Should I bleed my radiators?

Only if they are cold at the top and hot at the bottom. Turn off the system before bleeding. Have a rag handy and only turn the air key about a ¼  turn to release the air. You can feel the heat of the radiator to tell when to turn off. Check the header tank afterwards.

Is there some stuff I can put in my radiators?

Yes. This is best done in the summer months. If you are a bit handy the instructions are on the box. It is quite labour intensive and so to call an engineer is a bit expensive.

The main brands are FERNOX MB1 and SENTINAL.  The liquid inhibits the system and prevents corrosion.  To test the system, to check the strength of the inhibitor, get two clean jam jars. Using the air release from the radiator, drain a little water into one of the jars. Put clean tap water into the other jam jar. Find some steel nails and drop one or two in each jar. You will now be able to compare the two jars over the course of a couple of weeks. The radiator water should not cause the nails to go rusty if inhibitor strength is adequate.

Why is my water too hot?

Have you left the electric immersion heater on?

With some older systems the hot water is hotter in the winter when the heating is on. It is due to the heat from the boiler continually heating the water. If you have a dial on the hot water cylinder, check to see if has been moved. 

Why is my boiler making a noise?

Usually this is due to a build up of scale or sludge in the system. If the boiler is not very old, then it can be caused by the oil that the radiators were protected with when they were made, which is now in the system, or jointing flux used on the pipes, which is also in the system. Old systems are very hard to clean as anything too aggressive can cause a leak. Newer systems can be cleaned.  B&Q sell cleaners for the D.I.Y enthusiast, or in the trade we use a special pumping machine.

Why do some of my radiators get hot when they are not supposed to?

If they have always done this, then it is usually due to poor design of the system.

On most occasions it is due to a failure of a change-over valve which is sticking. Usually it will need to be replaced. Cost should be about £150. You could turn the radiators off in the summer. It will do no harm.

Do magnetic or electronic scale reducers work?

I have done some trials and they do seem to reduce scale.

They will not make the water any softer and it does take some time. I have had a magnetic devise on my incoming pipe and there is less scale in our kettle.
 

Have I Got a Leak?

If you have a gas leak you will be able to smell it. The smell is added to the gas. If you think you have a gas leak turn the gas off NOW and call Transco on 0800 111 999.

With water leaks they can come from four sources. The heating system, the hot water system, the mains water or from damp/ rising water levels under the property. If suspect you may have a leak that you cannot see here are some of the things you can check.

If you have a leak from a “combi” boiler the water gauge which is usually on the front will go down and you will need to top this up using your link, which in the trade we call the filling loop. You may lose a bit of water as a result of evaporation, or off course when you bleed the radiators, but you should not need to top the system up more than say once every three months. One of the weak spots on a combi is the pressure relief valve which releases water outside if the boiler overheats. These valves sometimes leak a little. During the period of dry weather you could string up an old tin can under the pipe that goes outside to check to see if there are any escapes.

If you have system with a small tank in the loft you can tie the ball float valve up with some string to prevent water getting into the system. Make a mental note of the water level in the tank and return after a period, depending on the severity of the leak, to check to see if any water has been lost.

Check around joints of radiator valves. If a wall is damp you may well have a very fine leak on the back of a radiator that is spraying onto the wall. If you get a torch, it looks like a cobweb.

Minor leaks on the heating system may be able to be cured by using “Internal Leak Sealer” which is available from plumbers’ merchants.

Leaks on the hot water system are noticed when the hot water will not get to temperature. No matter how high you put the boiler of immersion heater on the water just not get hot. This is because water is draining away from the cylinder. To check, if the valve is not jammed, turn off the supply that comes from the big tank and feeds the cylinder. Check to see if you have turned the water off tight by opening the hot taps. Turn on your boiler for hot water setting. Wait an hour, turn the water back on, and see if it is hot.

If you have water constantly overflowing from your small tank it is quite likely that you have a leak in your hot water cylinder. This is an internal leak that causes the domestic water to mix with the heating water that then overflows.

Mains water leaks usually will give a constant noise. Turn off the mains stop tap and see if the noise stops. Some water authorities can help with this.
 

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