The two main central heating filters are MagnaClean and Sentinel Eliminator, they both have the strengths and weakness's so which is the best? In my opinion I would have to say that the MagnaClean has a slight edge over the Sentinel Eliminator, but it is only because you can see it working. When you service the MagnaClean you can clearly see all the magnetic debris on the magnet and you can tell that its working, where as with the Sentinel Eliminator you drain the water into a bucket and don't really get to see the results. But the Sentinel Eliminator not only collects magnetic debris it collects all debris floating around your central heating system.
When it comes to which is the most user friendly The Sentinel Eliminator wins hands down, because all you have to do is place a bucket under the filter, take off the cap and open the drain valve and let the water drain into the bucket. If you are a DIYer doing it yourself, your less likely to cause any damage to you property or have any leaks. With the MagnaClean because you have to take the magnet out of its housing, if the O ring seal on the cap is damaged it may not seal correctly when you put it back together, also if you spill any of the black sludge onto your carpet it can be very difficult to get back out. So when you service a MagnaClean be very cautious and take your time.
There are a few simple test to determine if your central heating system requires a power flush or just a filter and chemicals. So first of all what you need to check is the radiators and search for any cold spots, usually these would be in the middle or the radiator where the sludge has mounted up. This only normally happens to old radiators.
The next easy check is do all the radiators get as hot as each other? if they do you probably don't require a power flush and may only need to have a filter installed, if they don't you need to check if the radiator valves are all open including any thermostatic valves you have fitted.Most thermostatic valves you can take the thermostat off and check the pin is moving up and down. Also it is good practice to balance the radiators so that they all take roughly the same time to get hot.
The last dry test which I will talk about is using a magnet to test if the steel particles are sticking to the wall of your pipe and either restricting the flow or causing a blockage. You can use any small magnet to do this test. All you have to do is run the pipe down any none magnetic pipe and see if it sticks. There are a few places on the system to do this test anywhere you suspect there to be a blockage/restriction also if you have an open vent system another place which collects lots of sludge is the cold feed from the expansion tank which is usually in 15mm pipe and positioned just before the pump or better known as the H because of how its piped.
If you have all these symptoms and have tested with a magnet the next thing you want to test is the water quality in your system and the only way to do this is by taking a water sample. So to take a water sample the best way to do this is switch the central heating on and let it run for about 10 mins then drain some water from a drain off point and inspect the colour of the water. If your water is black then a power flush will most probably be required but if there is only a small amount of particles in the water then you will probably only require a chemical flush and a filter fitting.
Thank you for taking the time to read my blog GGB Heating Solutions
MagnaClean filters are central heating filters which collect all the steel particles that float around your central heating system, which may eventualy cause blockages. We can supply and fit these from £160. We have been installing MagnaCleans for the past 8 years and find these to be the market leaders in central heating filters. These compact filters usually fit just under the boiler on the return pipe, so it can collect the particles before it gets into the boiler and causes any major damage to the boiler/system components. These are easily serviced, but please take your time and do with caution because if you get any of the sludge on to your carpet it is very hard to remove and will probably stain. Start by isolating the service valves(turning them quarter of a turn using the tool provided) and using the special tool provided to unscrew the top, once the top is loose fill a bucket with warm water, it is also better to wear some rubber gloves while doing this and put a dust sheet under the bucket and filter. Take the magnet out of the housing and turn the magnet upside down, then put the the magnet into the bucket and pull the plastic cover off the magnet(into the water in the bucket) and set the magnet down on a cloth wash the plastic cover and put back on the magnet, put back into the housing and tighten, turn isolation valves back on and bleed out the air using a radiator bleed key or small screwdriver, then check with some kitchen paper around all the joints for any leaks. these should be inspected within the first month of installation and on every annual boiler service.