Troubleshooting Heating | Boilers & Radiators

Troubleshooting: Your Heating System

If your radiators aren’t heating up properly, are leaking or your boiler doesn’t seem to be working, there could be some basic maintenance that you could carry out to attempt to rectify the problem before calling out a professional plumber.

How to bleed a radiator:

If your radiator is warm at the bottom but cold at the top it is likely that there is trapped air inside and that it needs bleeding, this is a simple DIY job and shouldn’t need the help of a plumber. In order to bleed a radiator locate the bleed screw, this is usually at the top of the radiator but can also be on the back made of brass or alloy. Switch off the heating and make sure both valves to the radiator at the bottom are open. A radiator bleed key can then be inserted into the bleed screw and turned anti-clockwise. Have a towel hkieron to catch drops. As you turn you should hear the hissing sound of air escaping, when water squirts you are finished, close up the valve and go to the next radiator.

How to fix a leaky radiator:

A leaky radiator can be caused by several things and your course of action will vary depending on what it is. Firstly a leaky radiator could be leaking from the spindle: this can be simply solved by tightening the nut with a spanner. Secondly it could be leaking at the coupling to the pipe, again tightening the nut with a spanner might be enough to stop the leak, if not, the olive may need replacing: loosen the cap nut, remove the fitting and replace the olive, smear with silicone sealant and then put the fitting back on and retighten the cap nut. A leaky radiator could also be caused by corrosion, in which case a new radiator will need to be fitted. You can reduce the likelihood of erosion by flushing out your heating system with rust inhibitor and water.

Troubleshooting: Pressure problems with combination boilers

Combination boilers that work on demand may stop working if there is a drop in pressure. This may be due to a leak in the heating system or a bleed valve that hasn’t been closed property. Check all your radiators. If there are still problems your boiler may need ‘topping up’ with pressure, this can be done through a filling loop. First you should check how much pressure your boiler needs, this should be indicated on the pressure dial of your boiler by a red line, if not, check the manual. If it is currently below the minimum connect the filling loop to your boiler, open the valve and slowly fill with pressure. Turn off when you reach the correct pressure as stated by the manual. Now your combination boiler can be used again normally.