Posted by: @kirsty-j

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@peterr here's hoping the op looks at this.

 

How are you getting on with new iboost?

I has a similar situation where my old one went pop after 6 years and so replaced like for like. 

I find the new one spends more time with the cooling fan running and no output to the tank. 

So far I'm very disappointed with it where as the original was far better. 

I'm looking at swapping it out but need the two outputs so when one is hot the second kicks in... Very few do this 

I'm also wary of the electrical noise that some cheaper units have with the thyristor controls. 

 

K

 

The Immersun unit has up to three outputs, but is on the expensive side.

@derek-m that's not a major issue, the Iboost Is pushing 300 quid and not saving me as much.

Posted by: @kirsty-j

↑

@peterr here's hoping the op looks at this.

 

How are you getting on with new iboost?

I has a similar situation where my old one went pop after 6 years and so replaced like for like. 

I find the new one spends more time with the cooling fan running and no output to the tank. 

So far I'm very disappointed with it where as the original was far better. 

I'm looking at swapping it out but need the two outputs so when one is hot the second kicks in... Very few do this 

I'm also wary of the electrical noise that some cheaper units have with the thyristor controls. 

 

K

 

I have an unused Iboost in the garage. It was working when it came out in 2019 to be replaced by an Eddi, when I got batteries . Iboosts (at least, that version) don't have the required tech to avoid competing with / discharging batteries.

Free to a good home. PM me if wanted.

@iancalderbank oooh...

Yes please,   where abouts are you, 

I'd be interested to know if the latest versions are different to older ones... 

The first one I had ran beautifully and I could divert to either the hot tank or other heaters

This new one seems to keep saying please wait check vents.. 

Iboost claims there are more temperature sensors on the board so it protects its components???? I just see it heat the water for 5 mins then shut down for 15,

K

Posted by: @kirsty-j

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@derek-m that's not a major issue, the Iboost Is pushing 300 quid and not saving me as much.

Before ditching the iboost, are you certain it has been correctly installed.

I know from experience with my Immersun unit, if the current transformer on the mains input cable is the wrong way round, it incorrectly assumes that you are exporting when you are actually importing, and vice versa.

@derek-m

Yep, defo installed correctly... It was like for like replacement. 

It does work but just tries to cool its internal components to often. 

But it sees the export correctly. 

K

@kirsty-j Sorry to hear about your issues, but I'm pleased to say that our new iBoost is performing just as well as the old one, well better really because we now have it connected to both immersions.  Not seen any issues with it trying to cool while not heating.  Generally the cooling fans are running whenever it is heating.

@derek-m good point. I had an iboost fitted 6 months ago. More recently had a 6.5kWh Growatt battery fitted to my Solar PV. I have found that charging the battery with surplus solar PV is no problem, the battery takes the power. But when discharging, the iBoost will sometimes fire up then shut down having not actually put any energy through the immersion. Seems to cycle, but the iBoost is apt to cycle anyway as I have it on quite a low minimum power setting of 100W. It doesn't drain the battery however, the battery is charged during low tariff hours and the power goes into the ASHP mostly, to see me though variable rate peak times on Cosy Octopus and some of the standard tariff times. I might up the minimum setting on the iBoost to 200W to see if that reduces the stop/start cycling.

Since I am planning to install a battery storage system in the future, this is one of the points I have been considering.

My present power diverter is set to divert power when my solar PV system is exporting 10W or more back to the grid. I believe a battery storage system could also be set to limit the amount of export, assuming you do not wish to do so.

My intention is two fold, one is to support running my A2A heat pump from both battery storage and solar when there is insufficient solar for full operation, or when one of those 'pesky' clouds appear, the second being to supply the overnight electricity demand of our home from battery storage, so that we don't draw power from the grid, even if it is only during the peak period.

On days when there is an abundance of solar generation, I would be looking to not only provide hot water, but also maybe provide some home heating and battery charging.

Obviously what I don't want is for my precious battery storage to be drained into the hot water cylinder via the power diverter.

@derek-m I think that unless you have a super efficient system of a big size, it's a big ask for power storage, hot water and heat.

@peterr this is the 2nd iboost.. (technically third) the first did over 6 years with no issues.

Ouput 1 goes to the immersion heater. This is the primary use.

Output 2 goes to an outlet for other heating devices.... So in winter there is a 2kw heater on the main room to keep the chill off the house.

Other times it is mainly different water heaters for hot tubs and pools (don't judge me... We all bought some covid crap 😛).

Number 1 worked like your description... Fan kicks in when diverting... 

Unit two I thought was faulty but it does the same as three...

When only diverting small amounts, the thyristor obviously does more work so the fan runs... But then it says check vents. Cooling. (I can't recall the exact words) 

It  kicks in and out the output every 5 mins or so... 

But ultimately it is not utilising all the available power.

Quite disappointed really.

I have not looked at the iBoost in detail since I have an Immersun unit, but I do believe that they operate in a similar manner.

The more power that is being controlled, the warmer the power electronics are likely to get, so the more likely the cooling fan will need to operate. Where is your power diverter located? Is it in a warm location?

The level of export power at which the diverter actually starts to 'divert' may be adjustable, it certainly is on the Immersun unit. So if your unit is set to start diverting energy once the amount being exported exceeds say 100W, and the excess power from your solar PV is only slightly over 100W, it may indeed start diverting this 100W excess. If the solar PV excess now falls to 90W, the diverter may be programmed to now stop diverting.

If you are finding that the diverter is starting and stopping diverting at low levels of solar PV excess, then this may be the cause. I would suggest reading the instructions to see if you can set the level for power diversion to a lower setting.