Would this immersion heater fit my tank? (Photos to show)

Galego

I am getting a plumber to fit me this 36" incoloy immersion heater to my tank (not sure about size of the tank). The one already inside works alright but too small and looking to get the longest I can fit to heat the water with the excess power from the solar panels.

Looking at the below photos would you say it'll fit alright?

Second choice would be going 30" or bend this 36" a bit (not if good idea).

Lenar3556

Your best bet would be to check with the cylinder manufacturer what is the max length element for that cylinder.

Usually the max length permitted is in the region of 150mm short of the max length that would actually fit. Not sure what happens if you fitted one that was close to touching the base, but there probably is some reason why they don’t recommend it.

The Continental Op

Now just to be awkward there is another option. The Willis Heater

https://mybuildingsupplies.ie/shop/plumbing-heating/water-heaters/willis-heater/

Its been discussed before here and is an ideal way of getting the maximum amount of heat into your tank.

Previous discussion

https://www.boards.ie/discussion/2058243718/fitting-a-willis-immersion-heater

Galego

https://www.boards.ie/discussion/comment/122131116#Comment_122131116

I read that these don't work well in hard water areas. I live in an area with very hard water so I disregard this option.

There seems to be at least 150mm once fitted (visually) to the bottom of the tank but I guess only once fitted inside I'll be able to tell for sure.

Otherwise I'll have to swap it for the same one in 27".

AndyBoBandy

where is the thermostat located on the longer immersion element? As if it’s not sitting any lower than the existing stat, it will still trigger ‘max temp reached’ at the same time (and with the same amount of water heated) as the older element.

Galego

https://www.boards.ie/discussion/comment/122131451#Comment_122131451

The on which it's already inside I've no clue but I guess it is pretty short as it only takes 3kwh to cut off the immersion.

These Tesla ones (27" & 36") come with a 18" stat. Would that mean it is pointless to fit the longer one then? I thought even though they both come with the same stat the longer one will still heat more volume of water otherwise what would it be the point for Tesla to sell the longer one?

AndyBoBandy

https://www.boards.ie/discussion/comment/122131467#Comment_122131467

I’m not so sure a longer element will heat more water…. Just heat the same amount of water faster…..

I toyed with the idea of a longer immersion element before, and was told it would be fairly pointless, and if I wanted to heat a larger volume of water a Willis was the only way to go….

Galego

https://www.boards.ie/discussion/comment/122131499#Comment_122131499

I am not an expert by any means but it'd seem pretty pointless for Tesla to sell immersion heaters longer than 23" if that was to be the case. I am confident the longer immersion will heat more volume of water regardless of the thermostat.

John.G

Of course a longer element will heat a greater vol of water than a short(er) one, thats how the dual element immersion works, as pointed out though, the problem is the stat, both its length, which may be less than 1/2 the element length and its top mouning, while you won't have to use ~1/2 the fully heated vol, cold incoming water will have to rise up a fair height before the average temperature of the stat falls to the stat cut in point, dual element immersions are far "worse", if you heat the "sink" portion to its cut out point, then no more heating if you change over to the "bath" until you use up maybe 15 or 20L of water. I don't know why one can't buy a single element immersion with a equal length stat which would certainly mean cylinder heating occurs far sooner. A destratification circulating pump would do the job but at greater expense. What is the cylinder volume?.

dathi

and dont forget to add a thermostatic mixing valve to the cylinder as a lot of people crank up the thermostat on the element to get more usage out of their solar resulting in scalding water at the taps

Galego

https://www.boards.ie/discussion/comment/122131574#Comment_122131574

It is 150L. I am fitting a single element as opposed to dual (it is hard to get dual incoloy elements anyway, not as available). I want to heat as much water as possible. I looked into a Willis but the hard water in my area will absolutely destroy it (I've seen it happing). I also purchased a circulating pump but my plumber put me off the idea and a longer element heater is the last option left for me.

Galego

https://www.boards.ie/discussion/comment/122132059#Comment_122132059

Not planning to crank up the thermostat on the element but yeap i think I'll add a thermostatic valve.