Iboost

shibli

Hi, 

I have just had my solar panel and battery installed along with a iboost on a east and west roof  installation and producing 20kw of electricity daily so happy days but I do have a question around the effectiveness of the iboost. 

The iboost is reporting it's diverting power to the our hot water cylinder but the water doesn't heat up sufficiently and I am forced to run the boiler to provide hot water. What's people general experience of the iboost and is there a particular way to run it or a setting I need to make. I assumed it was all automated and you just forget about it.

TIA
Shibli 

EcoScruples

Do you know how much power is being diverted to 6our iboost? Do you have any data?
If ìts only a few hundred watts being diverted then youll need yhatbover a considerable ammount of time.

How big is your tank? Do you heat it from cold or does it have some heat in it from the previous day?

It may not be an iboost issue, just a use issue.

QrizB

From your previous thread, you'd been quoted for a 4.8kWp system split E-W with a battery. Is this what was installed?

If it's set up correctly, your system will first meet any house load, then charge your battery, and only after that will it start heating your hot water.

If you've got a big hot water tank with the immersion heater positioned at a low level, it could take 10kWh or more to fully heast the water.

What sort of monitoring system do you have? Have you been exporting electricity to the grid these past few days? If export is low or zero, it would suggest that the system is working correctly and diverting all the surplus. If export is large, it might need adjusting.

thevilla

I'd agree with QrizB you need to establish if you're exporting to the grid to see if the iboost is working correctly.   I'd go further and suggest you should not have been sold the iboost if you also have a battery.  The days when you have sufficient surplus to fill the battery and also a hot water tank will be limited, depending on your consumption.   Taking into account any payment for exports, it'll likely be a long time before the iboost breaks even financially.  Iboost type devices are great for households on FIT as we get paid whether the generation is self consumed or exported.  You missed that boat but benefited from cheaper up front costs.

shibli

The system is a 4kw system, split between east and west roof.

It's been two days since installation so early days in terms of reported numbers but yesterday was about 1.5kw in total to the cyclinder - clearly not enough, however I did use the washing machine and dishwasher last few days as well as diverting to the 6.5kw batteries, so perhaps not enough power is being diverted to the iboost. Currently the panels are producing 2kw if the weather is decent.

The cyclinder is 250ltr. 

I have turned off my boiler but now thinking I may need to turn it back on to top it up.

Reed_Richards

Your iboost will send power to the hot water cylinder immersion heater until its thermostat reaches its set temperature. What temperature is the immersion heater thermostat set to?  Your boiler will operate on a different unrelated thermostat.   

paul991

ensure the stat on the immersion heater is set  to a  few degrees higher than your  gas . turn  off  the switch and there's a slot  to turn under the  round cover . the gas stat is the one secured with curtain wire to the outside on the tank. You  would have to be using hell of a lot of  power if you need gas for hot water this  time of year

JKenH

You report you only diverted 1.5kW to the cylinder in total (I presume you mean 1.5kWh). With a 250l cylinder you could almost lose that amount of energy overnight as the tank cools so if you were asking for hot water the next morning it is no surprise it wasn’t very hot. We have two hot water tanks with an iBoost fed immersion heater in each. The iBoost tends to divert 4-5 kWh of energy a day to the immersion heaters (combined) before reporting “water tank hot” and switching off. (After a couple of dull days I have seen as much as 16kWh diverted when the sun comes out). With a single tank for a couple of people you probably need to be diverting around 3-4kWh per day but more if you are starting with a cold tank. 

iBoosts and batteries don’t work well together as they are both fighting for the same excess energy.

paul991

have  you  monitoring on what you have  consumed  , generated , fed  back to grid and batteries, ?
I've a similar solar  immersion switch where you can control when and at what level  power is  fed to the immersion. my tank was insulated  with foam but i also put a red jacket on it which the insulation contractors gave  me

[Deleted User]

I have a MyEnergi EDDI solar diverter connected to my hot water tank. 

An East/West 4kWp array may well produce 20kWh in a day but the amount of solar electricity available for diversion depends on your house load (both in terms of instant power and kWh in a day) and the charging priorities set up by your installer (this is often related to the wiring configuration). For example, my home is set up for home loads first; battery recharging second; HW re-heating third and EV charging 4th. 

My battery will output at 5kW. It follows that if my panels are outputting at 3kW and my wife puts on the oven at the same time that the dishwasher is on, the battery will have to supplement the solar production. Once these high power devices are switched off then solar output will go first to the battery and then to HW cylinder re-heating. 

PV solar, even with a battery, isn’t ‘fit and forget’. As the nights draw in, management of your battery supply becomes key if you want to avoid Grid electricity use. From about September through to March, your iBoost will become an expensive paperweight - sorry. I have a much larger array than you do and it only outputs just over 100kWh in December. Most of my battery recharging in the Winter comes from the Grid.

shibli

Reed_Richards said:

Your iboost will send power to the hot water cylinder immersion heater until its thermostat reaches its set temperature. What temperature is the immersion heater thermostat set to?  Your boiler will operate on a different unrelated thermostat.   

It was set at 65c, the max, I have turned it down to 60c