The left flow pipe, is 'too hot to hold' its a case of touch it and let go right away
The right return pipe is 'nearly as hot' but i can touch it for 1 second.
would it help if i made a wee video?
i dont think i done the test correctly earlier
Come & Have A Dig At The O.P (mega banter thread)
- Thread starter robtherevelator1969
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The left flow pipe, is 'too hot to hold' its a case of touch it and let go right away
The right return pipe is 'nearly as hot' but i can touch it for 1 second.
would it help if i made a wee video?
i dont think i done the test correctly earlier
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Kettling is possible/likely if the flow rate is too low!
I would love to know what the real temps are.
Ian and the others are keeping quiet!
But they will all jump on me whatever I suggest. Unless of course it works and they will keep quiet.
Tony
Kettling is possible/likely if the flow rate is too low!
I would love to know what the real temps are.
Ian and the others are keeping quiet!
But they will all jump on me whatever I suggest. Unless of course it works and they will keep quiet.
Tony
Yes some other opinions would be nice to hear. I have taken a couple of videos to see if that helps. I also did the test on a metal kettle which was just boiled, the flow pipe is not as hot as this but its not far away.
click pics to see video
click pics to see video
We are all waiting with baited breath to see what conclusion you come to Tony
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...or can't be bothered.....
No Tony, for a low water content copper HE it can be more, 20 even.
You are a top 100 engineer so you will be able to suggest a remedy
Op, why is the new expansion vessel silver.
Is the pressure gauge jumping about when the kettling occurs? If not, put an end to this thread as there is nothing wrong. Leave the pump as is- you cannot and do not need to do anything The flow is as it should be or your burner would not fire as boiler has flow checking sensor. Temperature difference you decribe is adequate ( not perfect but adequate for this boiler) so sit back, brew a cuppa and enjoy reading a book or whatever takes your fancy
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A copper heat exchanger can operate with a higher temperature differential than 11 C.
But it has been traditional in the UK for non condensing boilers to be designed for use with a target differential of 11 C.
There is little difference in the efficiency of the boiler and a high differential results in a lower return temperature and that can risk condensation in the boiler after the heat exchanger.
The makers don't actually state their intended differential in the manual. They even quote a minimum CH flow temperature of just 35 C. I suspect continual operation at such a low flow temperature would probably cause condensation and then corrosion within the boiler.
Tony
But it has been traditional in the UK for non condensing boilers to be designed for use with a target differential of 11 C.
There is little difference in the efficiency of the boiler and a high differential results in a lower return temperature and that can risk condensation in the boiler after the heat exchanger.
The makers don't actually state their intended differential in the manual. They even quote a minimum CH flow temperature of just 35 C. I suspect continual operation at such a low flow temperature would probably cause condensation and then corrosion within the boiler.
Tony
Back to the problem.
In the absence of actual temperatures I would like to be sure the flow rate on CH is adequate.
The boiler MI do not mention it, but many similar models have a gauze filter fitted at the front of the isolating valve under the boiler. These are intended to be fitted to the return but some installers have wrongly fitted them to the flow. Do you think you have one on your boiler which can be removed to clean?
You may find this filter shown on the manual of the virtually identical model marketed under the Potterton brand name.
Tony
In the absence of actual temperatures I would like to be sure the flow rate on CH is adequate.
The boiler MI do not mention it, but many similar models have a gauze filter fitted at the front of the isolating valve under the boiler. These are intended to be fitted to the return but some installers have wrongly fitted them to the flow. Do you think you have one on your boiler which can be removed to clean?
You may find this filter shown on the manual of the virtually identical model marketed under the Potterton brand name.
Tony
It has nothing to do with tradition
A cast iron heat exchanger had to have 11 degree difference else risk of cracks appearing
Copper heat exchanger meanwhile does not have the issue. If you want to split hair, see no reason why a band c/d should be 11 and same boiler fitted with recuperator has to have 20 differential
The reason is that the Band B boiler is designed to condense inside the recouperator and thus deal with the resulting condensate. The flue components will be designed to operate with water rich flue gases.
The fan is between the heat exchanger and recouperator and so operating above the temperatures where there is a risk of condensing ( below 55-60 C ).
Tony
The fan is between the heat exchanger and recouperator and so operating above the temperatures where there is a risk of condensing ( below 55-60 C ).
Tony
I removed the gauze filter and it was slightly clogged with rusty sludge, i thoroughly cleaned it and refitted it, the kettling is still there. Now the chrome return fitting leaks, what is the correct way to fit the nut, there is 2 nuts, a big one and a smaller back nut. There is a filter on the diverter valve is that for HW only?
The div valve filter is cold water in and does not need to be touched in connect with your problem.
Only the cap nut needs to be removed to access to filter.
Where is the leak from?
Amusing that the manual forgets to mention the return filter!
Only the cap nut needs to be removed to access to filter.
Where is the leak from?
Amusing that the manual forgets to mention the return filter!
Is the cap nut the large one? I only have a shifter that size and it was a struggle tightening it, between the cupboard and the filling loop. There is a drip from the big nut. I dont want to over-tighten it and make things worse. Will i apply some LSX that i have?
I think you need PTFE on the union behind.
The cap nut ( the one to the front of boiler ) comes with a thin rubber deposit on the inside I think. There may be a fibre washer that will fit inside it.
Or PTFE stretched across the mating surface.
The cap nut ( the one to the front of boiler ) comes with a thin rubber deposit on the inside I think. There may be a fibre washer that will fit inside it.
Or PTFE stretched across the mating surface.
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