Increasing amount of water heated with the immersion heater, options?

[ericmark]

I know the Wilis system will heat whole cylinder, and a longer immersion will also heat more, I know renewing an immersion can rip the tank, and I would assume a pump could also circulate the water, the problem is the immersion has a 9 inch thermostat and only heats a bit at the top, so I get good weather and the water is hot, but with a couple of days of little sun so immersion not turned on, and water cold again, heated with the central heating it stays hot for 4 days, but not with electric, don't want to spend too much, what are my options?

Immersion only used when there is excess solar power, before solar panels always used the oil boiler to heat it.

 

[Jackrae]

Disconnect the in-element thermostat and fit a separate wall attached unit further down the tank

 

[DetlefSchmitz]

That won't help as the water below the immersion heater will not get heated. (see stratification)

 

[Jackrae]

That won't help as the water below the immersion heater will not get heated. (see stratification)

But there's been no mention of the length of the heater, only the thermostat.

 

[DetlefSchmitz]

I suspect he has a 14" element based on the picture in his other thread. To my mind, only an immersion heater with a longer element is likely to be much use in his situation. Although he keeps fishing for someone to tell him a Willis system is the answer.

 

[Jackrae]

Can you still get accelerator tubes for use with immersion heaters.

 

[flameport]

a longer immersion will also heat more,

That is the answer. Change it to a 27" immersion.

Anything else is just timewasting and whataboutery,

 

[ericmark]

I have tried to get a local plumber to fit a longer immersion heater, I am still waiting for a reply from him. I feel that's the best answer, but was looking for anything else which may work instead.