Hi all

Hope you are doing well

I have moved into a new property and bought an 8kw/10kwh Sunsynk system, with around 5kw worth of panels. Everything is working great, but I would now like to start optimizing my water heating. The relevant facts are:

1.   I think I have a 4kw 200l geyser that is on my non essential load
2. My wife and I use relatively little power during the day as we both work - I have an excess of PV from around 11 30 each day as the batteries are fully charged

I am concerned about investing in a system only to completely overhaul it, so I was thinking the following would be good first steps w.r.t the geyser:

1. Install a smart switch/timer - will likely set the geyser to be able to heat up between 12-4 pm each day
2. Move the geyser onto the essential load so that it can still have power during an extended fault - if it draws too much I can just turn it off with the timer
3. Retrofit a smaller geyser element to prevent exceeding my PV capacity
4. Retrofit some direct solar heating for the geyser

Does the above make sense or am I missing/overlooking something? Are there any recommended products to help with the above?

Thank you so much

I am not sure how necessary some direct solar heating would be if you connect the geyser to your essential load. If you have excess PV, why spend more money on your geyser? Keep things simple, heat your current geyser via your current solar system with the excess PV.

I do like the idea of having it on the essentials side if there is an extended power outage / fault. Since you only have 5KW of panels, then a smaller element makes sense so that you do not end up drawing from the grid and PV to heat the geyser - rather have it on for longer with a smaller element and heat it all from the excess PV.

 

In terms of timers, I quite like the Sonoff switches, I have one on my geyser and so far it's working well.

I have this one: https://www.geewiz.co.za/smart-plugs-switches/188964-sonoff-pow-r320-elite-smart-power-meter-switch.html?sfdr_ptcid=2961_617_692777366&sfdr_hash=76063156a736f1ca3f7a9d69636f957d&gclid=CjwKCAjwzo2mBhAUEiwAf7wjkmUTBmKcrQGMTxVKZpvhDaiaiCzh0b87-vy77cC2PPxybSlr-OZBghoCDCwQAvD_BwE 

 

Whether this is the correct smart switch / timer for you would depend, as this would not work without internet unless you make changes. However if you have a desire to add some home automation, this could be a better choice compared to a "non smart" timer.

If you want to do some home automation, then you have more options available and more conditions to base when the geyser should be turned on / off and no specific timer would be needed per say.

If you have no desire to go the home automation route, then keep it simple with a basic timer.

@PsyCLown If you don't mind me asking.

I'm looking at the same switch, did you simply replace your old db switches for this one, or did you put it after the breakers you already have?

I can't really seem to find if it can be used as a replacement for existing breakers basically.

5 hours ago, Chris Bongers said:

i can't really seem to find if it can be used as a replacement for existing breakers basically.

@Chris BongersYou need to keep the existing breaker and wire the smart timer after the geyser mcb otherwise you have no protection for the wire in overcurrent situation.

On 2023/07/29 at 10:22 PM, TaliaB said:

@Chris BongersYou need to keep the existing breaker and wire the smart timer after the geyser mcb otherwise you have no protection for the wire in overcurrent situation.

This is exactly it.

So Live In is from the MCB, live out is the wire going to the geyser itself (which was originally in the MCB) and then neutral you can just run a single wire to the neutral busbar to keep the wires to a minimum and keep things a bit neater.

 

The consumption info is really nice compared to the previous POW models. The button on the smart switch is just to turn the switch on / off, the screen displays the info and scrolls through the different info automatically. I was hoping the button would allow one to adjust the info which is displayed on the screen but that is not the case unfortunately.

However I find it more convenient to check the info on my phone anyways. Especially for the geyser considering it is not drawing a constant load and only turns on when needed.

It comes with the DIN rail mount in the box.

Edited July 31, 20232 yr by PsyCLown