One of my radiators has gone very sluggish. It is the small size microbore with twin entry valves. Worcester Heatslave Highflow Combi.
I think I should try a flushing / cleaner. Any suggestions for a good but cheap solution / method.
I am currently running with all rads off except the sluggish one and it isn't making much difference.
The cheapest *and* most effective solution would be to remove the radiator, take it outside, and give it a good wash out with a hose pipe. That is, if the problem *is* sludge.
Are you sure the pump is ok? Do the other radiators work ok when you turn them on? Does the dodgy radiator have a TRV? Are you sure that it's opening? Is the lockshield valve fully open?
I can' believe it is sludge in the radiator as it was taken off a few years ago - it is upstairs - others (downstairs) were removed a few months ago (for decorating ) and serious sludge has not been an issue.
However, with such small pipes I do suspect the pipes are restricted.
Not TRV. Lockshield fully open. Pump fine. Boiler upstairs - all downstairs radiators work well. I suspect that a dip in a pipe could get sludged up.
I guess I could try my homemade pressure washer - a hose adapter into the top plug of the radiator. However, with a laminated wood floor I am a bit paranoid about spilling water.
In that case, I think I'd *still* remove the rad, and flush its pipes thoroughly. Presumably it's a pressurised system - so you can use mains pressure to force water through to the valves - opening each valve in turn, and collecting the resulting gunge in a bucket.
I'd be less worried about spilling a drop of blackish water on laminate that I would on carpet.
It has a header tank (open vented).
Keep the ideas coming - any thoughts on chemicals? It has normally had an inhibitor in the system.
Hi, The twin entry valve could be your problem. In my experience these are not very good & sometimes cause a lot of problems. There is an injector tube that comes from the flow of the valve & runs along inside the bottom of the rad. This is so that the hot water is delivered to the far end of the rad, away from the return on the valve if you follow what I mean. Quite often this injector pipe comes off inside the rad, the result is as soon as the hot water reaches the rad it is away again down the return, so the hot water isn?t circulated through the rad. However you should still be able to feel some heat at the valve end of the rad. I have only ever seen this type of valve used on 8mm pipe. If you have no heat at all in the rad or the pipes going to the valve of the rad then you have a blockage. This could be in the injector pipe inside the rad. So remove the rad & flush it & check the injector pipe is there & not blocked.
If you have flushed out the rad & still you have no joy try doing this: Get hold of a rad valve, you are after the part that screws into the rad. (The tail) Remove the rad. Connect the tail to the rad. Connect a hose pipe top the tail. With the hose pipe on the cold tap open the flow side of the valve & then open the tap. If you here water movement it is clear. Have someone watch the header tank, as the level in it should start to rise if the pipe is clear. Do exactly the same on the return side of the valve, but close the flow you have just done. If both pipes are clear & you have flushed the rad when it was off it should work ok when reinstalled.
HTH.
I have re-posted this as when I read through the 1st one I had mad a few mistakes.
Hi, The twin entry valve could be your problem. In my experience these are not very good & sometimes cause a lot of problems. There is an injector tube that comes from the flow of the valve & runs along inside the bottom of the rad. This is so that the hot water is delivered to the far end of the rad, away from the return on the valve if you follow what I mean. Quite often this injector pipe comes off inside the rad, the result is as soon as the hot water reaches the rad it is away again down the return, so the hot water isn?t circulated through the rad. However you should still be able to feel some heat at the valve end of the rad. I have only ever seen this type of valve used on 8mm pipe. If you have no heat at all in the rad or the pipes going to the valve of the rad then you have a blockage. This could be in the injector pipe inside the rad. So remove the rad & flush it & check the injector pipe is there & not blocked. If you have flushed out the rad & still you have no joy try doing this:
Get hold of the tail part from a rad valve (the part that screws into the rad) Connect a hose pipe to the part that would normally screw into the rad & this will then connect to the rad valve to allow you to flush the valve. With your problem rad removed connect the tail to the rad valve. With the hose pipe on the cold tap open the flow side of the valve & then open the tap. If you here water movement, the flow pipe is clear. Have someone watch the header tank, as the level in it should start to rise if the pipe is clear & the cold water from the tap is forced into the heating system. Do exactly the same on the return side of the valve, but remember to close the flow you have just done. If both pipes are clear & you have flushed the rad when it was off it should work ok when reinstalled. HTH.
the return isn't. I suspect there is a very slight flow and the heat is quickly dissipated.
I was thinking of:
Place bowl under drain c*ck at opposite end of radiator - close valve and lockshield screw.
Open c*ck then observe flow from the drain with either the valve or the lockshield open. This should show which pipe is not giving much flow.
Connect mains water to radiator - open the valve which has indicated a restriction and back flush.
My concern is that the blockage may not yield.
I will probably take the radiator off (easy but messy) to check the nylon injector tube.
Thanks.
Yeah I would try your method first, as it may save you having to remove the rad, you may get lucky & the blockage will shift. If not I?m afraid its get your hands dirty time!
Hope you get it sorted, do let us know how you get on.
Regards, Tel.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.