**** me Agile you are an awkward **** at times, the "bucket test" is where you take rad off wall and open rad valves on end of remaing pipe into a bucket to see wht the flow is like, as was said before this will give more power than pump and may clear any blockage, jesus man "bucket test" i had 2 check myslef, never heard it called that, infact didnt think it realy had a name
Replacement radiator is colder at bottom than it is at top.
- Thread starter fluff29
- Start date
**** me Agile you are an awkward **** at times, the "bucket test" is where you take rad off wall and open rad valves on end of remaing pipe into a bucket to see wht the flow is like, as was said before this will give more power than pump and may clear any blockage, jesus man "bucket test" i had 2 check myslef, never heard it called that, infact didnt think it realy had a nameSponsored Links
just had the engineer at work explain the bucket test to me. Have my reservations of doing this but he assures me that after I take the pressure out of the rad, not much water will come out when I release the v/v's. He has also said not take take the rad fully off but to just pull the pipework back as it is microbore.
Need to pluck up the courage to do this. Probably at the weekend.
thanks everyone. Will let you know what happens.
fluff
Need to pluck up the courage to do this. Probably at the weekend.
thanks everyone. Will let you know what happens.
fluff
Think I’ve read through the pages and understood the problem; if not, sorry.
You probably don't need any more advice but I'd mention a few things as you're really giving this a go.
As it's a combi, if you're not filling the system as you open the valves for the bucket test the static pressure in the system will soon dissipate and the flow will be reduced to a trickle.
It will not flow much anyway as the system is sealed with no open tank in the loft and no air is getting into the top of the system to allow the water out (think finger on end of straw).
The bucket test would be relevant if you do the same test once on each valve of the problematic radiator (I assume you have a valve on each side of the radiator that's giving you the trouble and both pipes do not go into one valve on the same side).
The system will have to be charged to the same pressure each time for a comparative test. This way you could see any difference in water discharge from flow and return.
If you try to fill the system from the filling loop with a valve open to monitor the flow make sure the two people doing this can hear each other (one at the filing loop and one at the radiator) as you could over pressurize and then need a new pressure relief valve.
Keep the pressure gauge below 2bar during the process.
I must say I have misgivings about you doing this yourself but you seem gung-ho so more power to you.
As for the local guys wanting to powerflush. I have found the manufacturers of flushing machines do not recommend flushing microbore; they do not say it will do harm but they know results are at best mixed; you just can't get the mass flow needed and any loosened solids through the small bores. Tell the local guys if what they're recommending doesn't work and stay working for a week or two they shouldn't bother with an invoice for the job and put it in writing. i.e. put their time, advice and money where their advice is. You’re paying them £500 to fix it, not to not fix it. Anybody from a job centre or old peoples home can ‘not fix it’ and for less money.
Personally, not being a huge fan of microbore I would re-pipe the whole system but then I do not have to pay for it. If you love the house and are going to be there a long time, re-pipe.
Good luck.
You probably don't need any more advice but I'd mention a few things as you're really giving this a go.
As it's a combi, if you're not filling the system as you open the valves for the bucket test the static pressure in the system will soon dissipate and the flow will be reduced to a trickle.
It will not flow much anyway as the system is sealed with no open tank in the loft and no air is getting into the top of the system to allow the water out (think finger on end of straw).
The bucket test would be relevant if you do the same test once on each valve of the problematic radiator (I assume you have a valve on each side of the radiator that's giving you the trouble and both pipes do not go into one valve on the same side).
The system will have to be charged to the same pressure each time for a comparative test. This way you could see any difference in water discharge from flow and return.
If you try to fill the system from the filling loop with a valve open to monitor the flow make sure the two people doing this can hear each other (one at the filing loop and one at the radiator) as you could over pressurize and then need a new pressure relief valve.
Keep the pressure gauge below 2bar during the process.
I must say I have misgivings about you doing this yourself but you seem gung-ho so more power to you.
As for the local guys wanting to powerflush. I have found the manufacturers of flushing machines do not recommend flushing microbore; they do not say it will do harm but they know results are at best mixed; you just can't get the mass flow needed and any loosened solids through the small bores. Tell the local guys if what they're recommending doesn't work and stay working for a week or two they shouldn't bother with an invoice for the job and put it in writing. i.e. put their time, advice and money where their advice is. You’re paying them £500 to fix it, not to not fix it. Anybody from a job centre or old peoples home can ‘not fix it’ and for less money.
Personally, not being a huge fan of microbore I would re-pipe the whole system but then I do not have to pay for it. If you love the house and are going to be there a long time, re-pipe.
Good luck.
Last November you worked out that your heating requirement is 10kW and you have approx 13kW of rads, but your boiler gives out a minimum of 11kW. Now this is only needed in the depths of winter, when it is below freezing outside. Most of the time the heating requirement is probably less than 5kW. The only way your boiler can produce the low output is by cycling on and off. Every time it starts up, it runs at max output (28kW) but, as the rads can only give out 13kW, the water temperature rises very quickly. The boiler tries to compensate by modulating down to 11kW, but this is still too much, so it turns off. When the water has cooled sufficiently, it starts up and the cycle repeats - as you have found.
A typical solution looking for a problem to solve.
Wrong, it's all due to the oversized boiler.
Waste of money.
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Until you have done the bucket test you cannot consider the next step forward.
I wrote the "Bucket Test" for the FAQ ( anmd the "finger test" for a pump ) but I think that since then others may have edited and moved it around. If so thats a pity because I carefully write in simple language and in the correct order.
You might wonder why I dont spend more time writing help topics but its exactly because others then mess them around and spoil them.
Tony
I wrote the "Bucket Test" for the FAQ ( anmd the "finger test" for a pump ) but I think that since then others may have edited and moved it around. If so thats a pity because I carefully write in simple language and in the correct order.
You might wonder why I dont spend more time writing help topics but its exactly because others then mess them around and spoil them.
Tony
for once i am in total agreement with you
to much interference after somebody else takes the time to do the topic of course
to much interference after somebody else takes the time to do the topic of course
Agile, am I just doing the bucket test on the problem radiator only and can I just pull the pipes back without removing the rad?
If I have to do the bucket test on all rads, to I top up the pressure between checking each rad?
Thanks again
fluff
If I have to do the bucket test on all rads, to I top up the pressure between checking each rad?
Thanks again
fluff
M
mysteryman
As it is microbore and worked properly for years, and now doesn't, it is almost certainly partial blockage somewhere. Microbore was fine when properly installed.
By all means try the 'bucket test'. It may clear the problem. Otherwise, a powerflush.
This system is probably decades old. How old is your car?
By all means try the 'bucket test'. It may clear the problem. Otherwise, a powerflush.
This system is probably decades old. How old is your car?
Hi all
Just read vulcan's reply and I am now abit wary of doing this. I don't know if all these suggestions are a good idea for clueless people who know nothing about plumbing, although the theory sounds ok.
I have my old boss who was a Hospital Engineer also on the case. He has looked at the system. He thinks there could be a partial blockage and that there is a possible problem with the temperature sensor in the boiler. He has emailed the Alpha technical dept. on my behalf and will need to wait a few days before phoning.
In the meantime, I asked him about the bucket test and he told me not to bother with this.
He wants me to do the following.
1. Leave the system as it is, with all valves open.
2. Slacken a blank cap which is apparently on a 15mm pipe under the hatch underneath the house, and allow the water to come out (into a basin).
3. If only a small amount of water comes out, I should bleed one of the rads upstairs.
4. Shut off cap (this is the bit that I am scared of incase too much water is coming out and I can't get it closed quick enough).
5. Refill system.
6. Bleed rads
7. Repeat again until water clear?? Don't know if this will happen.
The other engineer at my work thinks that too much water will come out of the cap under pressure as all valves are open.
Therefore he suggests, fitting a hose with a jubilee clip to the draw off v/v under the floor and opening the valve with a hex key/spanner then possibly bleeding the rad upstairs (depending on the amount of water coming out). then following 4 to 7 above.
From what I have read on the internet, I think you can also open the fill loop from the boiler to flush main water thro the system but I think that you need to stop the water getting back into the boiler and not sure how you do this. Would this be correct?
Would it be advisable for someone who knows nothing about plumbing or heating to do this?
I am not sure if there are little v/v's to close the flow/return pipes for the DHW and CH underneath the boiler.
When you open the fill loop, does the boiler pipework need to be kept open as the water will need to go through the boiler or can the water just go through the pipework?
Sorry for all the questions. My husband is getting very annoyed with me as he does not want to do any of this and just wants a plumber to fix it. Unfortunately the local plumbers that I have contacted (3) only want to powerflush and they have all said that this may not work, there is no refund if it doesn't work and we would then be charged for them cutting back the pipework, starting at the manifold.
Any advice on the best route relating to the above would be appreciated. We will need to so something with the flushing this weekend, at the moment I am favouring the hose method without opening the fill loop at the same time. May be more time consuming but hopefully it will be more controlled without cutting off the pipework to the boiler.
ps the people at my work that I am getting advice off of deal with the large hospital plant, therefore they may not no as much as you guys with regards to household systems - not sure.
Thanks
Fluff
Just read vulcan's reply and I am now abit wary of doing this. I don't know if all these suggestions are a good idea for clueless people who know nothing about plumbing, although the theory sounds ok.
I have my old boss who was a Hospital Engineer also on the case. He has looked at the system. He thinks there could be a partial blockage and that there is a possible problem with the temperature sensor in the boiler. He has emailed the Alpha technical dept. on my behalf and will need to wait a few days before phoning.
In the meantime, I asked him about the bucket test and he told me not to bother with this.
He wants me to do the following.
1. Leave the system as it is, with all valves open.
2. Slacken a blank cap which is apparently on a 15mm pipe under the hatch underneath the house, and allow the water to come out (into a basin).
3. If only a small amount of water comes out, I should bleed one of the rads upstairs.
4. Shut off cap (this is the bit that I am scared of incase too much water is coming out and I can't get it closed quick enough).
5. Refill system.
6. Bleed rads
7. Repeat again until water clear?? Don't know if this will happen.
The other engineer at my work thinks that too much water will come out of the cap under pressure as all valves are open.
Therefore he suggests, fitting a hose with a jubilee clip to the draw off v/v under the floor and opening the valve with a hex key/spanner then possibly bleeding the rad upstairs (depending on the amount of water coming out). then following 4 to 7 above.
From what I have read on the internet, I think you can also open the fill loop from the boiler to flush main water thro the system but I think that you need to stop the water getting back into the boiler and not sure how you do this. Would this be correct?
Would it be advisable for someone who knows nothing about plumbing or heating to do this?
I am not sure if there are little v/v's to close the flow/return pipes for the DHW and CH underneath the boiler.
When you open the fill loop, does the boiler pipework need to be kept open as the water will need to go through the boiler or can the water just go through the pipework?
Sorry for all the questions. My husband is getting very annoyed with me as he does not want to do any of this and just wants a plumber to fix it. Unfortunately the local plumbers that I have contacted (3) only want to powerflush and they have all said that this may not work, there is no refund if it doesn't work and we would then be charged for them cutting back the pipework, starting at the manifold.
Any advice on the best route relating to the above would be appreciated. We will need to so something with the flushing this weekend, at the moment I am favouring the hose method without opening the fill loop at the same time. May be more time consuming but hopefully it will be more controlled without cutting off the pipework to the boiler.
ps the people at my work that I am getting advice off of deal with the large hospital plant, therefore they may not no as much as you guys with regards to household systems - not sure.
Thanks
Fluff
short answer no
do the bucket test
I've not read everything in detail, there's so much! So sorry if this is wrong or has been covered.
Likely to be blocked at the return manifold, partially. Stick some X800 in it for a week or so and try to use the problem rad on its own as much as possible. Doesn't cost much and won't do any harm.
Big double rads on 8mm is asking for trouble anyways.
Likely to be blocked at the return manifold, partially. Stick some X800 in it for a week or so and try to use the problem rad on its own as much as possible. Doesn't cost much and won't do any harm.
Big double rads on 8mm is asking for trouble anyways.
I was once asked to get a living room rad to heat up. I looked at it as it was newly installed (few months ago) and was a 1200 double on microbore.
The lady told me it had never heated up and she had not called the plumber back. Not a case of balancing as the whole house was on microbore so I politely refused and advised her to get someone in to repipe the big rad to 15 mm.
The lady told me it had never heated up and she had not called the plumber back. Not a case of balancing as the whole house was on microbore so I politely refused and advised her to get someone in to repipe the big rad to 15 mm.
Hi everyone
Tried the bucket test this morning on the problem rad.
Did the return end first. When we opened it, the water came out at a reasonable force but not too much water (although I did not have the valve fully open).
TRV end. The water came out at a reasonable force when turned to III, and there was alot more water coming out. More like a flow of water like what was coming out of the radiator when the valves where disconnected from the ends.
I though that when we turned off both v/v's, bled the rad until it stopped at the top, then unscrewed the v/v, the thought the water coming out of the radiator would have stopped, but it didn't.
I have attached a copy of the water which came out the TRV end. The water has bits of black stuff which disintegrates when rubbed between my fingers. There is also flakes of what looks like gold, is this copper? This does not disintegrate when rubbed.
There was alot of black flakes which came out in comparison to the amount of water which came out. I think the TRV end definately works because my husband turned it on when the return end was disconnected and the water forced my finger off the hole.
We then got brave and tried to do what my boss suggested. As you can see from the hatch and the pipework there is no room to get a bucket under the floor and I am not sure how quickly the water would shoot out the pipe under pressure. Also wasn't sure if the water flow would eventually stop.
My husband saw there there is an isolating point before the blank cap on the 15mm pipe at the manifold (you will see it in the centre of the picture). There is an isolating valve before it which was turned across the pipe. My husband turned this first to see if it was closed or not (bear in mind we do not know when it is open or closed). When he turned it slightly, water came scooting out of the end cap. Therefore he turned the valve back to the centre, dried off the end cap and we have kept an eye on it to make sure it is not leaking.
In hindsight, we wonder if it is currently switched off at the v/v and my husband turned it on therefore that is the reason that water came out.
What we were hoping to achieve was switch the water off at the isolating v/v, take the end cap off, try to put some sort of container in to catch the water, turn the v/v to open the water flow and control it via this v/v.
Would this have worked or would this v/v not be able to hold the amount of water back?
Hope this all makes sense.
Thanks again
![GALLERY]](http://[GALLERY=media, 25231][/GALLERY] [GALLERY=media, 25230][/GALLERY])
Tried the bucket test this morning on the problem rad.
Did the return end first. When we opened it, the water came out at a reasonable force but not too much water (although I did not have the valve fully open).
TRV end. The water came out at a reasonable force when turned to III, and there was alot more water coming out. More like a flow of water like what was coming out of the radiator when the valves where disconnected from the ends.
I though that when we turned off both v/v's, bled the rad until it stopped at the top, then unscrewed the v/v, the thought the water coming out of the radiator would have stopped, but it didn't.
I have attached a copy of the water which came out the TRV end. The water has bits of black stuff which disintegrates when rubbed between my fingers. There is also flakes of what looks like gold, is this copper? This does not disintegrate when rubbed.
There was alot of black flakes which came out in comparison to the amount of water which came out. I think the TRV end definately works because my husband turned it on when the return end was disconnected and the water forced my finger off the hole.
We then got brave and tried to do what my boss suggested. As you can see from the hatch and the pipework there is no room to get a bucket under the floor and I am not sure how quickly the water would shoot out the pipe under pressure. Also wasn't sure if the water flow would eventually stop.
My husband saw there there is an isolating point before the blank cap on the 15mm pipe at the manifold (you will see it in the centre of the picture). There is an isolating valve before it which was turned across the pipe. My husband turned this first to see if it was closed or not (bear in mind we do not know when it is open or closed). When he turned it slightly, water came scooting out of the end cap. Therefore he turned the valve back to the centre, dried off the end cap and we have kept an eye on it to make sure it is not leaking.
In hindsight, we wonder if it is currently switched off at the v/v and my husband turned it on therefore that is the reason that water came out.
What we were hoping to achieve was switch the water off at the isolating v/v, take the end cap off, try to put some sort of container in to catch the water, turn the v/v to open the water flow and control it via this v/v.
Would this have worked or would this v/v not be able to hold the amount of water back?
Hope this all makes sense.
Thanks again
DIYnot Local
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