Yes it does, but attempting to diagnose your problem on the basis of where it's the same or different to another "similar matter" isn't going to go nowhere fast.
Do you, or do you not, observe black/dirty water when you vent the rad(s)?
a blocked cold feed/cure?...
- Thread starter liverpoolboy
- Start date
Do you, or do you not, observe black/dirty water when you vent the rad(s)?
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when i bleed the upstairs rads the water doesn't come out, one of the rads had a trickly but then nothing.
downstairs they bleed, and the water is black.
is this a cold feed blockage????
downstairs they bleed, and the water is black.
is this a cold feed blockage????
OK, so something is blocked, either fully or partially.
OK.
Have you done what I prescribed in order to determine the answer to that?
Have you read the sticky topic and provided all the information about your system that it asks you to?
just done it and the water does top back up. so not a blocked feed?? (well it can't be) what could the problem be? could it be sludge in the rads? it has only started happening (or so it seems) recently, but maybe it has been building up over a period of time...
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The test is not whether it tops back up, but whether it drains away and empties the cistern, with the water off.
Frankly, I'm slightly skeptical that you did the following in 10 minutes:
1. Shut off the water.
2. Climb into the loft.
3. Sponge out the F&E cistern.
4. Reinstate the supply and allow the F&E to fill.
5. Shut off the water again.
6. Locate and open a drain cock, and release at least 4 gallons.
7. Shut the drain cock.
8. Climb into the loft and check the level.
9. Wash your hands and return to the computer.
10. Type and submit your post.
And that's without the usual loft antics, such as gashing your forehead, tripping over stuff, finding a wasps nest (the hard way), finding the vinegar, etc....
If you say so.
Yes. It could also be in many other places.
Sludge builds up slowly, not suddenly.
sorry i did not sponge out the f & e. I just closed off my main stopcock which supplies it. and drained from downstairs for a couple of minutes water into my gulley. it came out ok. and the cistern level was the same when i checked.
should i do it again in the step by step order you listed?
also i know sludge builds up over time, and if it is not a blocked cold feed, do you suggest any cleaner i could use ?
also about your first point there, surely if the system does top back up then it's not a blocked cold feed?? i know it is to see if the water drains away, but if it does and water didn't top back up that WOULD mean a definite blocked feed??
should i do it again in the step by step order you listed?
also i know sludge builds up over time, and if it is not a blocked cold feed, do you suggest any cleaner i could use ?
also about your first point there, surely if the system does top back up then it's not a blocked cold feed?? i know it is to see if the water drains away, but if it does and water didn't top back up that WOULD mean a definite blocked feed??
1. Shut off the water.
2. Climb into the loft.
3. Sponge out the F&E cistern.
4. Reinstate the supply and allow the F&E to fill.
5. Shut off the water again.
6. Locate and open a drain cock, and release at least 4 gallons.
7. Shut the drain cock.
8. Climb into the loft and check the level.
9. Wash your hands and return to the computer.
10. Type and submit your post.
****don't empty the complete system with the F & E turned off. air will enter and you will have another problem!
Just empty the system with the F & E still on and get a mate to stand in the loft and watch it refill.
2. Climb into the loft.
3. Sponge out the F&E cistern.
4. Reinstate the supply and allow the F&E to fill.
5. Shut off the water again.
6. Locate and open a drain cock, and release at least 4 gallons.
7. Shut the drain cock.
8. Climb into the loft and check the level.
9. Wash your hands and return to the computer.
10. Type and submit your post.
****don't empty the complete system with the F & E turned off. air will enter and you will have another problem!
Just empty the system with the F & E still on and get a mate to stand in the loft and watch it refill.
This isn't compulsory, but it removes the risk of debris in the F&E being dragged into the system.
Some people think that it stops bits of rust and magnetite being drawn in, but I'm more concerned with bits of rotting rodent, bird feathers, wasps, wood, roofing felt, plastic shavings from when the cistern was installed, insulation, and some other very odd things that I've found in F&Es over the years.
Do what you like, but the test is not whether it tops back up, but whether it drains away and empties the cistern, with the water off.
How can anyone propose a cleaner, or a cleaning method, when the problem isn't yet diagnosed?
WTF? The water to replenish the cistern comes out of the float valve, not up the expansion pipe.
No, but I now see where you're confused.
It would mean a blocked cold supply, which is a similar sounding thing, but an entirely different fault with an entirely different solution.
When people talk about a "blocked cold feed" in an open vented heating system, they are referring, exclusively, to the connection from the F&E cistern into the path of the circulating water.
Really? Well he's gonna have to drain it all anyway, and pretty soon, whether or not the c.f. is blocked.
According to you that will create some unknown problem of as yet unimaginable proportions.
I think you are getting my posts mixed up!
I know the feed/pipe from the bottom (base) of the F & E which tops up the CH / Primary circuit is the COLD FEED.
When I said if it tops back up it is not blocked, I meant if the F & E tops up the CH/PRIMARY circuit pipework when water was drained from it from a low drain off valve!
This is what I meant. I know a blocked supply pipe (rising main)!! is a different case!!
So if this cold feed pipe is NOT blocked, as proven (but I will do the test again as you stated the steps out kindly for me) - it must be an accumulation of sludge over the years.
If it is this, do you recommend any good cleaners for sludge removal, or is there something else it could be?
I know the feed/pipe from the bottom (base) of the F & E which tops up the CH / Primary circuit is the COLD FEED.
When I said if it tops back up it is not blocked, I meant if the F & E tops up the CH/PRIMARY circuit pipework when water was drained from it from a low drain off valve!
This is what I meant. I know a blocked supply pipe (rising main)!! is a different case!!
So if this cold feed pipe is NOT blocked, as proven (but I will do the test again as you stated the steps out kindly for me) - it must be an accumulation of sludge over the years.
If it is this, do you recommend any good cleaners for sludge removal, or is there something else it could be?
OK fair point softus. drain the F & E cistern / primary/CH pipework through a low draincock. (tie up the float or turn the stopcock to it off first).
if all the water empties (allow a bit more water into the F & E) - then drain that too. if this all empties you know there is no blockage and that the cold feed is fine for definite.
Then release the float arm/turn the stopcock back on and let athe F & E fill again.
Go round bleeding all your rads, from the lowest ones upwards. And the pump also.
if all the water empties (allow a bit more water into the F & E) - then drain that too. if this all empties you know there is no blockage and that the cold feed is fine for definite.
Then release the float arm/turn the stopcock back on and let athe F & E fill again.
Go round bleeding all your rads, from the lowest ones upwards. And the pump also.
lol, I meant stand in the loft by the F & E!!!
Ha!!! Sounds fun!!Not at all, I'm just reading the words that you wrote!
OK.
OK!
OK!!
I tend not to share your confidence in that diagnosis.
For example, you don't you know exactly how blocked various things are. If you have no flow through a given rad, then it's quite possible that no chemicals will change that situation. A powerflush will almost certainly overcome that difficulty, but it's an expensive process.
The problem with a blocked system is in knowing the extent of the blockages. It could be anything mild to catastrophic. I've just replaced all the rads in one house because two had leaked and the rest were about to.
If you aggressively clean the system, you could expose latent leaks.
You could circulate some X400, which will loosen a lot of deposits and put them in solution for you to drain out. Personally, given the weather we're having, I'd then remove each radiator in turn and flush it out in the garden.
You then have to decide whether or not to replace the rad valves while you're at it. I certainly wouldn't put back any old TRVs, and if you already have them then now would be a good time to fit some.
sorry it was my fault the way i worded it, making you think I was talking about the cold supply!!
Is there any way I can find out the extend of the blockage/problem etc ?
None of my rads are leaking.
I wonder why only the top rads are blocked / sludged up (possibly) and not the bottom floor ones? Maybe they will also get blocked/sludged up over time...
If I flush each rad through in the garden do I just flush through with a hosepipe and mains water? No cleaner? Should I do the pipework beforehand with the cleaner you recommended?
Tahnks for helping me, you've been helpful even though I made it confusion for you!!
Is there any way I can find out the extend of the blockage/problem etc ?
None of my rads are leaking.
I wonder why only the top rads are blocked / sludged up (possibly) and not the bottom floor ones? Maybe they will also get blocked/sludged up over time...
If I flush each rad through in the garden do I just flush through with a hosepipe and mains water? No cleaner? Should I do the pipework beforehand with the cleaner you recommended?
Tahnks for helping me, you've been helpful even though I made it confusion for you!!
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