combination cylinder

[billybishbosh]

Anyone explain how the hot taps get pressure? Cheers..

 

[dextrous]

Other than from the head created by the integral CWS, they don't

 

[billybishbosh]

There is no head created, otherwise it would be a `header` tank. They actually work when installed on same level as a bathroom. Seen loads don`t understand how, and why make them? Anyone with experience of these, now`s yer chance.....Ta... bungalows have `em...all the time... it`s `Mortati` When all else fails.............

 

[dextrous]

There is no head created, otherwise it would be a `header` tank. They actually work when installed on same level as a bathroom. Seen loads don`t understand how, and why make them? Anyone with experience of these, now`s yer chance.....Ta... bungalows have `em...all the time...

The CSW part is above the tap outlets. There is therefore a working head of pressure

Untitled

• dextrous
• 27 Jan 2010
• 1

 

[brig001]

Are you sure it's not a small thermal store with a header tank at the top? We have an Albion Mainsflow which has an internal coil to heat the hot water at mains pressure. I was confused at first because the shower head is higher than than the header tank bit.
HTH,
Bri.

 

[billybishbosh]

Thought distance between header tank and cylinder created pressure?

 

[glasgowgas]

head pressure not pressure

 

[billybishbosh]

It`s gravity, pressure is pressure.......created by the distance from the tank to the cylinder if not so, why higher the tank to improve the pressure at hot taps? I`m asking about combination cylinders & how they work. I don`t know, also how does a thermostatic shower work? it`s height is about the same if not higher than integral tank on a bungalow

Puzzler innit........

 

[dextrous]

I'm ok with taps anywhere below the height of the top of the cold water in the CSW. As for where a shower head is above this, that really is a mystery if there's no pump installed.

 

[billybishbosh]

Strange.....whole pressure thing is baffling, if these work ok, what`s the point of a header tank? what creates the pressure in the cylinder to push hot water out?

 

[wademec]

Are you sure it's not a small thermal store with a header tank at the top? We have an Albion Mainsflow which has an internal coil to heat the hot water at mains pressure. I was confused at first because the shower head is higher than than the header tank bit.
HTH,
Bri.

Its probably the above mentioned. is there a coil on the cylinder with a control valve? Is the HW at mains pressure?

 

[electronicsuk]

Strange.....whole pressure thing is baffling, if these work ok, what`s the point of a header tank? what creates the pressure in the cylinder to push hot water out?

Not to drag up a sore subject, but it works because the outlets (i.e. taps) are lower than the water level in the header tank. Having a separate header tank and cylinder usually increases the vertical distance between the water level in the header tank and the outlet (as the header is usually located in the loft), hence increased pressure and flow rate at the outlet.

You could still have equal performance to a separate header/cylinder setup by putting a combination cylinder in the loft. I realise that certain members here wont agree based on a previous, shall we say, discussion - but I invite you to try it.

 

[dextrous]

Not to drag up a sore subject, but it works because the outlets (i.e. taps) are lower than the water level in the header tank. Having a separate header tank and cylinder usually increases the vertical distance between the water level in the header tank and the outlet (as the header is usually located in the loft), hence increased pressure and flow rate at the outlet.

You could still have equal performance to a separate header/cylinder setup by putting a combination cylinder in the loft. I realise that certain members here wont agree based on a previous, shall we say, discussion - but I invite you to try it.

I think that the op's experience includes observing combination units providing hot water outputs at heights above the unit itself. This defies the law of gravity and, unless they are indeed mains pressurised units, a complete mystery.

 

[electronicsuk]

I think that the op's experience includes observing combination units providing hot water outputs at heights above the unit itself. This defies the law of gravity and, unless they are indeed mains pressurised units, a complete mystery.

Indeed, I'm not quite sure how that would work.

 

[wademec]

Strange.....whole pressure thing is baffling, if these work ok, what`s the point of a header tank? what creates the pressure in the cylinder to push hot water out?

Not to drag up a sore subject, but it works because the outlets (i.e. taps) are lower than the water level in the header tank. Having a separate header tank and cylinder usually increases the vertical distance between the water level in the header tank and the outlet (as the header is usually located in the loft), hence increased pressure and flow rate at the outlet.

You could still have equal performance to a separate header/cylinder setup by putting a combination cylinder in the loft. I realise that certain members here wont agree based on a previous, shall we say, discussion - but I invite you to try it.

Indeed it will!