Hi folks,

I have an 8kVA Sunsynk inverter, and am trying to figure out the best way to manage the geyser. I do have the kellerza/sunsynk HomeAssistant integration set up, as well as the Sunsynk/intelless app.

When I had the geyser on the home load, I never saw any indication that it was actually benefitting from the available surplus solar power, and I'd get to just after midday and see my panels effectively stop generating power because the batteries were full, and the load was small.

So I got my installer to move the geyser to the AUX port on the inverter. But now I am struggling to figure out how to keep the water hot! 🙂 The Sunsynk settings are not making a whole lot of sense to me. The first day I had it, it ended up draining my battery, even though the grid was available!

And now I am playing around with the settings and thresholds, and I just cannot get it to run when I think it should.

Can anyone suggest the easiest way to have a simple "AUX on/off" switch in Home Assistant, and I can make logic there that actually makes sense to me? Otherwise it looks like I am going to have to ask my installer to move the geyser back to the "home load" position in the DB.

The clever guys will probably respond, but I can confirm how it works on my installation.

 

Under Work Mode, the box is ticked for "Limit to load only".  If I see there is excess power, then I untick that box and switch on the geyser which then runs on the solar.  Once it is hot and automatically switches off, I then tick the box again to prevent it running from the battery later on.  It is manual for now, but it works.  I would also like to get to a point where it can be automated like some guys do.

My whole house, including 2 geysers, dishwasher, washing machine, tumble dryer, all runs on the "backup/essential load" (UPS) side of the inverter.
I have some timers that limit geysers to heat up (sequentially) between 10:30am and 17:00pm when the sun is usually shining.

Just like @system32 mentions, I also run my geyser on the essential loads side also with a smart timer, that only switches the geyser on after 12pm and disables it again before 2pm.
Works great for my wife and I. Never had any issues with water temps even mid winter.
I also tried the aux sometime back using various settings and found running the geyser on essentials worked much better.

13 minutes ago, system32 said:

My whole house, including 2 geysers, dishwasher, washing machine, tumble dryer, all runs on the "backup/essential load" (UPS) side of the inverter.
I have some timers that limit geysers to heat up (sequentially) between 10:30am and 17:00pm when the sun is usually shining.

Do you only have a 2kW element in your one geyser and a 3kW in the other?

My base load during the day is around 2.2kW then there is washing, etc inbetween too.  My geyser has a 4kW element, so I need to plan when I can switch on the geyser as I quickly run out of peak pv and I try not to use battery during the day.  I have started looking at automation through HA, but the learning curve is quite heavy and I don't have the time to invest for now.

Interested to see the feedback on the HA integration for future use.

16 minutes ago, PearlJam said:

Do you only have a 2kW element in your one geyser and a 3kW in the other?

My base load during the day is around 2.2kW then there is washing, etc inbetween too.  My geyser has a 4kW element, so I need to plan when I can switch on the geyser as I quickly run out of peak pv and I try not to use battery during the day.  I have started looking at automation through HA, but the learning curve is quite heavy and I don't have the time to invest for now.

Interested to see the feedback on the HA integration for future use.

Correct.
The first geyser has a 3kW element 300l Kwikot - it is connected to a Solar water heater (thermosyphon) , I boost it at 10:30 to 65C and let the sun heat it further during the day - this has a GeyserWise timer.
The 2nd geyser has a 2kW element 100l Kwikot  used in a cottage with 1 resident - this has a Sonoff Geyser timer.

If it's overcast, the geyser will draw from the battery.

According to the SunSynk 8kW manual, the inverter is able to pass through 50A (~11kW) when grid connected.

10kW UPS Load ~ 4.9kW from Solar PV + 3.5kW from battery + 2.0kW from Grid
The numbers don't add up exactly as there is some lag, but close enough.
The inverter is inverting ~8.4kW

To date I've not yet had the inverter trip.

I need clarification on using the aux. If I wire the geyser directly to aux (i.e. disconnected from non-essentials) does the Sunsynk use the mains if there is not excess solar and battery is within the limits set? Or does it only provide voltage when those limits are valid so that one needs to have a switch to change to mains if heating required and solar and battery are outside the limits?