Willis Heating System

[SUNRAY]

Thanks. That's the sort of thing I mean.

I'm more accustomed to 4" pipework though.

 

[JohnW2]

Who said it would?

Well, for starters (assuming I have correctly understood what they have been writing) ...

..... Provided the water coming in at the bottom will keep the thermostat below the level its set at it will keep heating the water. It should work no matter what the height of the element in the Willis is in relation to the tank ....

.... The Willis is also able to heat all of the water in the main cylinder down to where the Willis cold connection joins the main cylinder at the bottom.

Just to confuse the situation further the heat source may be higher than the storage vessel.

The Willis one assumes can heat whole tank .....

It will heat it, to where the base of the Willis connects to the main cylinder - which can be much lower that the standard immersion heater reach, in the usual cylinder.

Let's not forget that a heat source in a tank of water can and will heat the entire tank eventually ...

.... The Willis enables a similar size of main cylinder, to store much more water, heated to the desired temperature, than does a normal immersion heater system.

(I'm not sure I fully understand the last one of those!)

So ... do you agree with 'them' or with me?

 

[ericmark]

I see nothing wrong with any of the statements. The side "boiler" we hoped it did not boil the water, on the Aga stove, was piped the same way as Willis. Today we use a hot coil, and the water in the boiler is not the same as water behind the hot tap, but in 1954 when parents house was built it was.

But I can't remember how long from lighting the fire it took to get hot water at the taps.

 

[SUNRAY]

I see nothing wrong with any of the statements. The side "boiler" we hoped it did not boil the water, on the Aga stove, was piped the same way as Willis. Today we use a hot coil, and the water in the boiler is not the same as water behind the hot tap, but in 1954 when parents house was built it was.

But I can't remember how long from lighting the fire it took to get hot water at the taps.

The solid fuel Agas were renowned for boiling the water, right up as far as the cistern in the loft, the problem occurred when more than one person (or inexperienced) used it. Do they still specify GI cylinders & cisterns?

More than once I recall my grandmother pouring water into the fire.

 

[JohnW2]

I see nothing wrong with any of the statements.

So, to be clear, are you saying that you believe that the entire contents of the cylinder (right down to the bottom) will get heated to something approaching 'target temp' by an immersion fairly close to the top (or, indeed, 'half way up') of the cylinder or by a Willis heater at the same height from the bottom of the cylinder?

 

[ericmark]

yes

 

[JohnW2]

yes

Ah! Thanks for confirming.

EFLI (or anyone), can you help me resolve this confusion?

 

[robinbanks]

I'm more accustomed to 4" pipework though.

That must have been a bit of an adjustment for the wife

 

[SUNRAY]

That must have been a bit of an adjustment for the wife

Nee bo'er

 

[Harry Bloomfield]

Unless I have completely misunderstood, some people seem to have been saying that a Willis system can (eventually) heat the entire contents of the main cylinder, but I have (I hope) been consistently saying that I don't understand how it can significantly heat water in the cylinder which is 'lower' than the Willis heater.

No, a Willis, can only heat up the water, above the level of the Willis bottom inlet pipe. That can be much lower than a vertical immersion heater reach.

What do you mean by 'more fluid' - less viscous, perhaps?

OK a reduced viscosity then.

...but I still don't really see what this has got to do with our discussion

Obviously, the lower the viscosity, the more fluid, the more easily it will rise, and flow from the Willis cylinder, to the main cylinder.

 

[Harry Bloomfield]

So, to be clear, are you saying that you believe that the entire contents of the cylinder (right down to the bottom) will get heated to something approaching 'target temp' by an immersion fairly close to the top (or, indeed, 'half way up') of the cylinder or by a Willis heater at the same height from the bottom of the cylinder?

yes

No!

An immersion heater, operating in the actual main cylinder, can only heat the water ABOVE the element location.

A Willis system is able to heat the water in the main cylinder, irrespective of the height/length of the element, The Willis, given enough time, will heat all the water in the main cylinder, as far down as the bottom (cold) Willis connection.

 

[SUNRAY]

Just to confuse the situation further the heat source may be higher than the storage vessel.View attachment 408441
I have expectation there would be reduced efficacy/efficiency.

I recall a friends non pumped heating installation in a very old house with a solid fuel boiler and a radiator one floor below it which was only ever 'warm to the touch' at best until he rerouted the heating return pipe from upper floors down via the lower floor to include the lowest radiator.

 

[EFLImpudence]

EFLI (or anyone), can you help me resolve this confusion?

I am a bit confused with all the different replies and with whom to agree.

I would say that at first glance this does not look possible:

However, perhaps it is just not coloured accurately.

For example perhaps nearly ALL the water in the Willis should be pink and indeed pinker - i.e. hotter and less dense - than the water in the cylinder by the time it has been moved so that circulation will be maintained - albeit slowly.

It does seem an odd way to install the Willis. Why would it be done like that?
Would a solid fuel back boiler upstairs heat a tank downstairs?

 

[Harry Bloomfield]

It does seem an odd way to install the Willis. Why would it be done like that?
Would a solid fuel back boiler upstairs heat a tank downstairs?

Not the best way, but I would suggest yes - it would work. The water has to rise in the Willis cylinder, drawing cold in from below, and moving the hot to the main cylinder.