Replacement radiator is colder at bottom than it is at top.

[DP]

There is only one way to solve a problem and thats at the scene.

Tony, your statement this time holds little water, in fact I would say it is invalid as Fluff had posted enough information to choke a horse. If you say you needed to be in front of the boiler in this case, then it can only be construed that you were too preoccupied to put forward your ideas that boiler should be range rated (when it cannot), carry out bucket test (when the bucket test has big holes in it) and calling people that had visited site previously, names or questioning their professionalism.

I come here looking for what other guys have to say, from which I endeavor to hone my skills. It would appear you come here to run others down from an uppity stand thereby shooting yourself in the foot.

""You might wonder why I don't spend more time writing help topics but its exactly because others then mess them around and spoil them.""

Above is regards bucket test, which was carried out to no avail. You and half the country (if attending the call) could have carried out this test till the cows come home, and still the location of blockage would not have been established. If you pride yourself as good engineer look at drawing submitted by Chris and apply your bucket test. I cannot see how you could pinpoint the blockage.

If you want to dissect this post, I am game. It was quite clear where the defect lay long before I was invited to attend site.

You said

It needs balancing! BUT if you have a modern boiler there should be a differential of 15-20° C across flow to return.

14 degree differential was posted on page 1.

If so what balancing has been done?

No balancing was needed except the big radiator that was repiped as suggested by D Hailsham

Danny, if you read the last eight pages you would see that they have already done the bucket test and it indicates good flow to each valve.

You dont seem to recognise the other problem of short cycling because the CH power is set at max.

Whats needed is to set it to minimum to prolong the firing time and to minimise the anti cycle time to reduce the boiler off time.

NONE of above was valid..

Posted: Sun Aug 29, 2010 8:32 pm Post Subject:

Above post by Chris is what switched the lights on for me.

There is no more point in beating about the bush here. Let it be said some fine gents who regularly post here have shown their professionalism by posting valuable information here. To Tony I say, read the 20 pages and you might learn something. It pains me to say this as you are a clever man with large reserves of knowledge which is hidden by your constant belittling of others in the trade

 

[OLLIE20]

Sorry Agile

don't be feeding his freakin ego it's big enough already

It was sarcasm kev, so hard to get it across in writing

 

[Agile]

Danny, I would still find the bucket test as a very valuable indicator of the water condition and the potential flow rate to that particular rad.

When Fluff did it she said bits of black stuff came out! Thats a very positive indicator that there are bits in the system which may have restricted the flow in the boiler/pump etc.

It also indicated that both pipes to that rad were clear. In that case as we had no info on the lengths of feed tube or rad powers we could not come to any conclusion on the suitability of 8mm to supply it. Obviously on site you were able to judge that it needed 10mm.

How would YOU rate the people who had attended before, including a Alpha staff engineer who was unable to see that the boiler was blocked, the plumber who fitted this replacement rad without realising the need for a 10mm feed or the Homeserve people who apparently visited more than once?

Tony

 

[fluff29]

Hi guys

Haven't things heated up on this thread over the weekend.

From a customer point of view, this is the service I received:-

Alpha engineer - repipe the radiator, nothing wrong with the boiler - he should have realised that the boiler wasn't performing correctly.

Alpha agent (on behalf of Alpha/Homeserve) - was at the boiler twice, replaced pump and stated that a PIPE (not boiler) was blocked and needed a powerflush.

Plumber 1 - best to fit new boiler at £1800 .

Plumber 2 - repipe rad, pipework to upstairs and new manifolds.

Plumber 3 - powerflush required.

Plumber 4 - repipe radiator.

My old boss - he diagnosed diverter valve but this was ruled out by people on this forum.

As Dan has said, I supplied huge amounts of information. Some people are making catty comments that I should have done a repipe 9 months ago but this would not have helped the whole system. I had stated on various occasions that it did not seem normal that if I had the heating down at 5, it would cut out after only a few minutes - I could see that this was not right but just did not know how to sort it. I could also see that there was hot water getting to the all rads therefore didn't think there was a pipework blockage and this is what stopped me getting a powerflush. It was only through me gaining a better understanding on this forum that I realised how my system worked.

I think that if I had got a few of the other people from this forum out to my house, they would have headed straight to repiping the rad and would then have discovered that this did not improve the problems all over.

Hopefully you can now all leave this thread on the basis that Dan did an excellent job and diagnosed a fault that nobody (other than I think Tony or Chris if they had come to my house) could identify.

I think Dan listened to everything that I said and realised that there was a wider problem going on other than the rad. Has made me realise that I should have looked at the whole system to begin with rather than only focusing on the problem rad.

Thank you all again.

Fluff

 

[DP]

Tony you need to sit down and visualise what takes place during you busket test. I am suggesting your bucket test needs to be retought. While it is a valid 'test', in its present form it can give you misleading results.

 

[Agile]

Then please start a new thread Danny and we can discuss the best ways that a bucket test can be conducted and, most importantly, interpreted.

I totally agree that at first sight it seems a very simple test with nothing more expensive that an old bucket!

But the results which it can give are first a good indication of dirt lying in the feed pipe, the colour and materials suspended in the main system water content and finally an indication of the flow rate through each leg of the connections. The interpretation of the latter requires a degree of skill as it will differ between pump and rad tests, pressurised or gravity systems and the length and bore of pipe feeding the test point.

In this case it demonstrated that both legs were apparently reasonable clear and presented similar flow rates. That does not necessarily indicate that the flow rate during use would be adequate as this was a new rad without any past history. Of course whilst it did not identify the actual fault, it did eliminate several possibilities.

The other purpose of the bucket test in cases like this one are to "blow" any debris out of the pipes because the pressure presented from a sealed system is many times that provided by the pump.

Back to this thread, although its not clearly defined it seems that the basic problem was the diverter manifold section was not fully returning to the rest position and thus allowing part of the flow to pass through the plate HE to the return within the boiler and thus elevate the return water temperatures causing the boiler to turn off prematurely.

This action was reduced when a tap was run at a slight flow as it reduced the temperature of the returning leakage through the secondary heat exchanger causing the boiler to fire for longer.

If thats the case, then at one point Chris did imply that feeling the temperature of the plate during CH would have indicated the diverter valve was leaking. Unfortunately that suggestion was lost amongst all the other discussions on possible causes.

Tony

 

[DP]

The test in question is relevant to this thread, therefore it needs to be part of this thread to bring the discussion to final conclusion.

But the results which it can give are first a good indication of dirt lying in the feed pipe, the colour and materials suspended in the main system water content and finally an indication of the flow rate through each leg of the connections. The interpretation of the latter requires a degree of skill as it will differ between pump and rad tests, pressurised or gravity systems and the length and bore of pipe feeding the test point.

I cannot see what skill is required to determine near equal flow of water during discharge. Even a layman looking at discharge would say something like 'Martha one of your pipes is blocked. I better get that ex plumber boyfriend of your's with 17 kids and another one on the way, to come look see what he can do'

Tony tell me if I my understanding of the bucket test is correct. Let the said bucket test be conducted at a radiator. Turn both rad valves off. Remove radiator. Place bucket under one valve and open valve. Close valve and repeat test with bucket under other valve and repeat test. Visual recall indicates if flow from each valve is similar. Have I missed anything? Remember boiler is a combination appliance not an open vent heat only boiler.

 

[DP]

Tony, take it you have opted to ignore this tread having assumed your bucket test is flawless. My question was, have I understood how a bucket test should be applied?

 

[bluey831]

aww .. gee ... fluff ..... it just aint gonna be the same around here without your problem!!

Actually, most knowledge is gained from the time it takes to try, test, evaluate, try again etc. If everybody were able to fix a problem first time every time, there would be a lot less knowledgable professionals out there.

PS - Can't wait for your next problem ....

 

[Agile]

Tony, take it you have opted to ignore this tread having assumed your bucket test is flawless. My question was, have I understood how a bucket test should be applied?

Its not "MY" bucket test although I did probably first introduce it to this forum under that name.

I am sure that ever since modern central heating was introduced many of those looking for faults have used a "bucket test" in one form or another.

There are several varients of how to do it and that depends on the main purpose and who is doing it. I have outlined above, in general terms, the typical way it can be used and some of the information that can be gleaned from it.

Remember, a test is just a test, its something which can or should be done as part of logical fault finding procedures. For example I always view the flue terminal before I start and then test the three mains connection wires to chassis. They rarely identify the faults but they do eliminate some faults and particularly do important safety checks before I touch the appliance.

Tony

 

[DP]

Tony you said you wrote the bucket test

I wrote the "Bucket Test" for the FAQ

that being the reason why I said 'your' bucket test.

Bucket test as described in FAQ has big holes in it. That is all I am saying

 

[Agile]

I did write it FOR the FAQ. But it was only a description of how it can be done but is not patented or controlled so you are welcome to do your own version as you see fit.

Tony

 

[DP]

Thanks for your response Tony. So, the test as it stands can be used but it may not produce results that can be relied on.

 

[Deleted member 105431]

Can we have another 21 pages of shyte please?

 

[DP]

For goodnes sake, this is a discussion forum. If a forum member does not wish to participate in a discussion, he can choose to ignore the thread.

It may be total cowpat to some forum members but nevertheless, it has been viewed nearly 12,000 times.