Heating not working correctly

[pinkynotthebrain]

Hi,

I know very little about the set up of our heating but here goes...

We have a boiler in our bedroom with a myson pump attached near it. This obviously pumps the water round the radiators. However the downstairs radiators are not coming on although the upstairs ones are piping hot.

Every time the heating is turned on there is a clunking noise near the boiler (about every 10 minutes), followed by a swooshing/spattering noise from the loft as the water is circulated around and into the tank. The tank then overflows and the water then comes out of the overflow pipe.

I have tried bleeding the radiators and there is very little air in them. I have also adjusted the level of the water in the tank but this seemingly doesn't help as it continues to overflow after the sputtering noise.

Can anyone make suggest anything prior to calling out a heating engineer?

 

[Durgo]

//www.diynot.com/forums/viewtopic.php?t=37170

 

[JohnD]

if it has recently started pumping over, and you have made no changes to piping or parts, it could be a buildup of sludge. This might happen if it did not have inhibitor; or if it has been leaking and fresh water topping it up has washed the inhibitor away.

A bottle of Sentinel X400 will cost you about £15 in your plumbers merchant or DIY shed, and will do no harm, it may do a lot of good. This is not an acid or aggressive cleaner and does not damage radiators even if you leave it in for weeks. Beware of other types of cleaner. However it is not an inhibitor so does not stop future corrosion.

you will need to drain out the loosened sludge, flush clean, refill with inhibitor after a couple of weeks

If the water goes very black with a couple of hours of adding the X400, that will be the sludge being broken up and washed around in the circulating water (good).

If you find sludge and can afford £100 for a Magnaclean (DIY fit) it will trap residual black sludge long-term.

If any part of the system is blocked 100% solid, the chemical will not be able to flow down the pipe to the blockage. Partial blockages however will be improved. Closing all rads but the cold one will help.

The level of water in the F&E only needs to be a couple of inches above the outlet pipe at the bottom. Bale and sponge out any sludge from it.

 

[bengasman]

Carp in the system and limescale in the boiler. Another customer for a powerflush with fx2