Ordinary radiator- move water inlet to top tapping?

[Colin Stamp]

that flow path increases and other channels become a path of less resistance.

flow that makes their resistance equal. You could get all the flow going up the first few channels if they were very wide.

If you want to pursue the electrical resistance analogy, then you'll have to extend it to include convection.

You could do that by putting a voltage source in each channel, pushing flow up that channel. The voltage of the sources will depend on the temperature difference across their channel. In practice, the first channel will have its bottom end much hotter than its top end, so its voltage source will be large and most of the current will be driven up that channel. Any current that sneaks along the bottom tank will raise the temperature at the bottom of the second channel, increasing the voltage of the source in that channel and causing it to suck up any remaining current that the pump, strangled by the lockshield valve, can provide.

Cheers,

Colin.

[harry]

or is throttled down in the course of balancing until the flow is adequate.

ter tees (Harry will have to google for that), with convection alone drivin g nearly all of the flow through the radiator. That suggests to me that the differential pressures across the rad, whether provided by pump or convect ion, may be of a similar order of magnitude.

adiator TBOE with the flow in the bottom. I don't see why it wouldn't work, is all.

good idea about something else.

I am very familiar with with one pipe heating systems having spent forty years in the NHS where they are universal in older hospitals thanks. And without diverter tees (which can be sweep tees, or cup tees), radiators work very poorly indeed. This should be obvious or it would not be neccessary to make such tees. The main reason for a top connection is to give the diagonal connection (and hence a better water distribution pattern) and to put the control valve at a convenient height.

[harry]

won't happen, I'm saying it wouldn't anticipate it happening.

fferent masses of the H&C water columns.

Radiators do exist where the bottom manifold is split with a divider halfway along. This forces all the water up the vertical channels, into the top manifold and down the remaining channels and back into the other side of the bottom manifold. No top connections are provided in such radiators.

[Onetap]

I'm starting to change my mind on this. That image does seem to show all the hot water (white area) going straight up the first channel. Presumably the waterways are oversized (relative to a pipe) for the flow rate that is going through them.

I'm not wholly convinced since the 'before' picture on that site does not show what I'd expect from a sludged-up radiator. There are numerous therma l images of radiators on the internet, but none as 'black & white' as this one; they've probably chosen an image that best suited their sales patter.

TBOE connections would seem to be a waste of time unless you want the val ves high up. The extra heat is probably due to the extra pipe.

[hallnorm99]

e radiator is throttled down in the course of balancing until the flow is a dequate.

diverter tees (Harry will have to google for that), with convection alone d riving nearly all of the flow through the radiator. That suggests to me tha t the differential pressures across the rad, whether provided by pump or co nvection, may be of a similar order of magnitude.

t a radiator TBOE with the flow in the bottom. I don't see why it wouldn't work, is all.

oody good idea about something else.

I have read this whole thread with interest thanks. It strikes me that it w ould be just as good to connect the f and r at the top on opposite sides of the radiator. Any thoughts>

[The Other John]

Yes, it seems you can't read dates! This is a 5 year old thread!

[Fredxx]

At least he had the decency to quote the post he was replying to.

[Vir Campestris]

Return must be at the bottom. Otherwise the cold water at the bottom never moves, and the hot runs across the top.

Andy