Solar Immersions and Megaflow CL tank

OffGridLiving

Dave_Fowler wrote: »

An immersion heater is similar to a light bulb (except it produces only heat). The Immersun acts like a normal dimmer switch you can use for the lights, only the control of the 'dimmer' part is automatic.

Dave F

This is what I originally thought, but then when people were talking about having to find and fit smaller 1 or 2kw immersion heaters, I started to wonder if it was right. I've had a look on various websites selling immersun type products and they never mention the immersion heater, apart from how to hook it up.

<EDIT> I found this website: http://www.4seasonssolutions.co.uk/solar-pv/solar-pv-immersion-heater-relay.htm, which seems to indicate that the exported power has to reach a certain threshold before it turns on the immersion heater, rather than a 'dimmer' switch that exports any excess power?

"We sell two options:

1) Includes the AGS1133 Intelligent solar switch & two way CT clamp which will turn ON & Off you immersion at pre set export power times. This is a great option for 4Kw PV systems but please check your existing Immersion heater element size as most households have a 2.7 - 3kW immersion. In this case you'll set the switch on (Export) to trigger at 2.7kW.

2) Includes the APR-3 power reducer. This halves the power of your existing immersion heater to half its current rating. I.e. if you have a 3kW immsersion this will become a 1.5kW element. What ever size PV system you have your much more likely to be exporting 1.5kW on a regular basis than 3kW that is required in option 1."

Also...

"
Most households have been fitted with a 3kW immersion heater; it may not be possible for the Solar PV system to generate that much
[FONT=Arial,Arial][FONT=Arial,Arial]spare energy[/FONT][/FONT]. 3kW is quite high and therefore may over load the spare energy available.

Currently the
[FONT=Arial,Arial][FONT=Arial,Arial]only option [/FONT][/FONT]for homeowners with high kW immersion heaters is to purchase a 1kW or 2kW immersion heater and hire an electrician and plumber to remove and replace their existing one. However, this can be very time consuming and very expensive and this is where homeowners may consider just selling the surplus energy back to the grid.
[FONT=Arial,Arial][/FONT]
[FONT=Arial,Arial][FONT=Arial,Arial]The solution: [/FONT]


[/FONT][FONT=Arial,Arial][/FONT]
[FONT=Arial,Arial][FONT=Arial,Arial]ECO[/FONT]



[/FONT][FONT=Arial,Arial][FONT=Arial,Arial]2 [/FONT][/FONT][FONT=Arial,Arial][FONT=Arial,Arial]Water Heating System[/FONT][/FONT]

. The package includes a [FONT=Arial,Arial][FONT=Arial,Arial]Clip-on sensor[/FONT][/FONT], an [FONT=Arial,Arial][FONT=Arial,Arial]Intelligent Solar Switch [/FONT][/FONT]and a [FONT=Arial,Arial][FONT=Arial,Arial]Power Reducer[/FONT][/FONT]. "


I dunno what to think now.

OffGridLiving

Ahhh, I get it now. I found this on the immersun website:

"The immerSUN will wait for around 130W of export before any power is delivered to the immersion heater, once the water heating begins, however, the unit will be able control power in 1% steps, so for a 3kW heating element, the minimum power output is about 30W"

I guess that's why these sorts of devices are quite expensive. They reduce down the power as in option (2) in the product I linked above, but they do it dynamically as the surplus power dictates, starting from a low threshold of 130w up to 3kw.

Brilliant technology. I love the sort of green tech that is 'fit and forget', I believe that this is the only way for it to gain mainstream acceptance.

DATMAN_2

sorry, I have got lost in the advice given.

What is the best way I should proceed so I can switch on Megaflow electric switch so the solar immersion works correctly.

Also if 900w is being produced will the 3kw heater turn on with this 900w?
thanks

DATMAN_2

Fully working now...so the answer is that the Megaflow CL tank is compatible with the Solar Immersion unit !!

210l of free hot water on a bright day !!

[Deleted User]

Fantastic bit of kit eh!

Since installation the ASHP has not kicked in to heat the water, happy days