which is the best F&E System between these 2 Systems?

andyr123

andyr123

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Hi all I am just wondering which setup do plumbers/heating engineers like the best out of these 2 systems with CH header tanks in the Loft? - and is one better than the other or do they both work as good as each other , any caveats with either?

*Diagrams not - no-where near - drawn to scale. The Header tank for hot and cold aps and toilet cisterns is much much bigger in the loft space than the CH Header tank.


FIG. 1.)
1700404840736.png




FIG. 2.)
1700396917895.png
 
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I’m not a plumber or a heating engineer but neither of those look right to me. Certainly, from memory, not the same as a vented system I had.
 
Mottie said:
I’m not a plumber or a heating engineer but neither of those look right to me. Certainly, from memory, not the same as a vented system I had.
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The second diagram looks correct, as far as it goes, but I cannot make any sense of the first one....

What is the oval shape?

Why does the water in the CH, appear to mix with the HW circuit?

Why is there a need for a vent pipe up from the oval object, to the cold water tank?
 
Harry Bloomfield said:
The second diagram looks correct, as far as it goes, but I cannot make any sense of the first one....

What is the oval shape?

Why does the water in the CH, appear to mix with the HW circuit?

Why is there a need for a vent pipe up from the oval object, to the cold water tank?
Click to expand...

Oval thing is the copper DHW cylinder in the airing cupboard

the pie from the copper cylinder is the vent pipe going to the header tank (bends over the top of header tank)

the water does not mix , the CH goes into the copper cylinder (immersion tank) by coil (forgot the proper term for it)
 
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andyr123 said:
Oval thing is the copper DHW cylinder in the airing cupboard

the pie from the copper cylinder is the vent pipe going to the header tank (bends over the top of header tank)

the water does not mix , the CH goes into the copper cylinder (immersion tank) by coil (forgot the proper term for it)
Click to expand...

Not a plumber, but that layout seems correct, but I question the need for the vent pipe for the HW - I suspect, that when you turn an HW tap on, that air might be drawn down that vent pipe, along with the hot water.

Your cold water tank will of course be much, much bigger than your F&E tank for the CH, unlike your diagram.
 
Harry Bloomfield said:
Not a plumber, but that layout seems correct, but I question the need for the vent pipe for the HW - I suspect, that when you turn an HW tap on, that air might be drawn down that vent pipe, along with the hot water.

Your cold water tank will of course be much, much bigger than your F&E tank for the CH, unlike your diagram.
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Yep sorry the diagram not done to scale at all and that's about my level of doing a diagram (looks like it was done by a 4 year old I know :) )

You need an expansion pipe for the DHW cylinder in the airing cupboard as water expands as it gets hot, plus its a safety thing as well , as if the immersion element got stuck in the 'on' position (by faulty thermostat) then rather than blow up the tank, the pressure will come out into the header tank (and then eventually overflow the tank) and then exit to the outside of the house via a overflow pipe from the header tank
 
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andyr123 said:
You need an expansion pipe for the DHW , as water expands as it gets hot, plus its a safety thing as well , as if the immersion element got stuck in the 'on' position (by faulty thermostat) then rather than blow up the tank, the pressure will come out into the header tank (and then eventually overflow the tank) and then exit to the outside of the house via a overflow pipe from the header tank
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It will be able to back flow, up the pipe, leading to the CW tank, so the vent pipe is unnecessary. I assumed you had simply omitted the overflows, for clarity of the diagram ;)

Modern immersion heater thermostats, have to include a secondary thermal trip, to prevent the water ever boiling.
 
1 is pretty standard fare for old heating systems. 2 could be used.

Both are entirely obsolete and no one with any sense would be installing them today.
 
They're both poor and out of date layouts. With modern boilers and the minute waterways why would you not have a sealed system?
 
Unless you have solid fuel boiler sealed system all the way.
The first drawing only for gravity hot never fully pumped.
Second single feed/vent can work on fully pumped but I personally would never use .
Unless system filled very slowly have a tendency to air lock.
 
flameport said:
1 is pretty standard fare for old heating systems. 2 could be used.

Both are entirely obsolete and no one with any sense would be installing them today.
Click to expand...

A more expensive way to have hot water, but it suits how some people live their lives, and their home - like me ;)
 
Gasguru said:
They're both poor and out of date layouts. With modern boilers and the minute waterways why would you not have a sealed system?
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For a good many reasons, such as a nice, simple boiler, where much of the system can be repaired DIY, or by a basic plumber with no extra qualifications to open a room sealed boiler.
 
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