Solar iboost not working

[davesparks]

The immersion heater should be on a separate cable back to your consumer unit (fuse box) and connected by fixed wiring to the iBoost/immersion heater. (For example using a Screwfix 58085). In my opinion this should be looked at by a qualified electrician because there are potential safety issues there.

That screwfix item is a switched fused connection unit, this is the wrong thing to use if it is to be connected to a seperate circuit and is not much better than a 1363 plug as it still has a 13A fuse and is rated to only 13A.

 

[Grumpy_Wombat]

Yes, agreed about the chosen part.

I stand by my point that an immersion heater should not be connected to a 13 amp plug-socket combination because it's very near the current limit of a quality part, let alone some that can be found.

It should of course be a 20Amp switch. So agreed about part of the comment.

 

[davesparks]

Yes, agreed about the chosen part.

I stand by my point that an immersion heater should not be connected to a 13 amp plug-socket combination because it's very near the current limit of a quality part, let alone some that can be found.

It should of course be a 20Amp switch. So agreed about part of the comment.

It's is near to, but on the right side of 13A.

I agree it is far from ideal, but it is within the rating of a 1363 plug and socket. I've often done it as a temporary measure.

But this is also powering the immersion heater through an iboost unit, this regulates the power so that it won't always be the full rating of the immersion heater flowing through it.

 

[marconi]

Mary 12345: Davesparks is top of the game in electrical wiring matters so if you have an queries or want confirmation about what needs doing and price following the electrician's visit he is a good contact. I have stitched him up but I am sure he will be chuffed to help.

 

[Grumpy_Wombat]

Indeed. If the 13amp socket is genuinely on a separate supply then theoretically OK as you say (assuming a decent quality one). Since there are 16 solar panels available (some 4Kw max) then the iBoost might be at full power for a number of hours.

My concern would be that the 13A socket is part of a ring and not a separate connect …. and there's no easy way of determining that sight unseen.

Not that this diversions helps resolve the initial issue of it not taking current anyway …...

 

[Mary 12345]

I have now checked the emersion heater via the iboost on boost and it heated the water tank up fine so all working. Now thinking it must be the sender or clamp (which is definitely the right way up). Everything seems to indicate that the iboost is receiving from the sender but it must be sending a there is not enough excess energy (even when there is) permanent message. Any ideas on if it’s more likely to be the clamp or the sender unit itself?

 

[marconi]

Mary 12345: Because it is no cost and easy to do as a test - please reverse the direction of the clamp and see what happens. Be careful to keep your fingers away from the ends of the power cable and have an attendant. Turn the electricity off while you do it. You will need some sun electricity of course to see if the iBoost starts to work.

If it makes no difference then restore the direction to how it was.

 

[Grumpy_Wombat]

Changing the direction won't hurt, although it was clearly stated that it was the right way round, having been replaced the wrong way round some time ago.

Given that the tests seem to have eliminated every other possibility then it does seem to be that the fault in the sender (or the iBoost) itself. Probably the best way is to buy a replacement sender clamp and sender from Marlec and try those in various combinations. (They do accept returns less postage if you find that that the new parts don't fix it).

And, of course, in the meantime, bear in mind that you can press the boost button on sunny days without incurring electricity costs.

 

[marconi]

Mary 12345: I recommend you don't spend any money on a new sender or new clamp yet. The fault I reckon is in the iBoost. Pressing the Boost button temporarily circumvents the power electronics of the iBoost using a relay ( a switch) which connects the immersion heater directly to the mains - you have confirmed already this functionality is working.

It is probable - in my view - that the power control electronics for the iBoost functionality have failed. The iBoost power control electronics uses a semiconductor switch not a mechanical one like a relay because it can be turned on/off very quickly. By varying the ratio of on to off time the iBoost ensures as much average power flows to the immersion element as is being exported from your PV system. If this semiconductor switch - a triac- stops working or whatever controls its on/off, then no power will flow to the immersion heater irrespective of whether there is excess PV power being exported.

You have had a good offer from Marlec to test your device at #11.

 

[Grumpy_Wombat]

All depends which is better for you. Post #11 indicates that they are not accepting returns at the moment although that might change soon. And, of course it has to be safely disconnected. However, If you assume that it is the main unit that is faulty then this is the correct course of action. At least we've moved on from a flat standby battery.

If, however, eliminating any sender problems sounds useful, the downside is the return postage and the time taken. Always assuming that Marlec are open enough to ship spares.

Unfortunately, there's no one good definitive answer at this stage and I regret I can't give you one.