Mitsubishi Ecodan not switching according to Cost Boiler selection

That's good to know that the HP is able to switch the gas boiler. As you say, now to crack the intelligent switching.

As a side note, if you are on the SVR or a Fixed Price tariff it it might be better to switch the gas boiler on temperature when we know the COP is going to be lower. I've always seen ‘electricity price switching’ in the context of dynamic electricity pricing when you get cheap off peak (or half hour slots) in exchange for very expensive peak prices but I'm happy to continue to try and diagnose the price switching issue.

As a matter of interest have you inherited the system because if you had it fitted then a user manual should have been provided with it and that would be useful to have at this stage.

Peter

PS BPlightlog and I are forum volunteers and we happily take on challenges like this for customers

Hi Peter! 

You are very kind and I will explain why this setup to understand why :). There are backup advantages, eco-green benefits but the price is the most relevant as my house consumes 22.000 kWh heating during the winter.

The gas boiler system was installed some time ago and is still working fine. But with the gas prices spiking when russia started the war in Europe => i installed a PV system. No government incentive but there is a benefit that allows me to store the produced electricity in the network until 2030. It means that the PV produces 16.000 kWh during the summer and i consume when i needed paying some fees for transport and distribution (0.5 /kWh) . Electricity needs, except for heating, are 9.000 kWh.  The rest of 7.000 for heating (with a COP around 3 to cover for the 22.000 kWh heating needs stated above). The entire system was calculated and it is ok. But the gas price now is low and i should take advantage of this, the savings are important on the 22.000 kWh heat

I also run HomeAssistant smart home connected to everything, including HP and PV and i am able to change temperatures in the system, on water flows, and make lots of logical switchs. But the options do not include any Configuration changes as to force switching on boiler. These are done from the unit LCD disply and are done with the system completely shut down (the display informs you the the system will shut down to change these settings). Smart home looks like a smarter remote :)

Mitsubishi has this facility in the options, i checked all the menus, read the manuals, again and again and it looks fine. 

I am pretty sure that it is somewhere something to activate. etc. 

The manual is

https://torn-climatizare.ro/wp-content/uploads/2018/07/Manual-de-instalare-Mitsubishi-Electric-ERSC-VM2D.pdf

and here https://confort.mitsubishielectric.fr/sites/default/files/imported/ECODAN-ERS-ERP-GENERATIONE-NOTICE-SAV-OCH815A.pdf 

see page 84 / intelligent settings. 

Model ERSC…

Thank you.

Ok. Needle in a haystack time! I could wade through all the controls and figure out what each setting should be or do one of my favourite tricks when we have a complex piece of equipment not working and compare it to that.

There is a shed load of DIP switches on page 16 and 17 and as the Default is for a working system it would be useful to know if there are any differences beween the Default and what is set on your unit. Probably best to print the pages out if you can then fill in the results and let me know any differences. It also gives me a chance to think of a Plan B if that doesn’t work and to read through the other document.

Peter

Many thanks for that. I've had a quick scan and I've noted that there are switch setting for different models and fitment options. Do the switch settings agree with what is fitted in terms of the HP model and the various ancillary units fitted?

I must admit that the very obvious switch settings that would have caused the problem are correct.

Another point which is worth noting, as a former software engineer, is that board fitted switches are normally ony read once just after the power up reset period and are never read again. If the HP unit has never been switched off and on it may be worth doing that. It would happen anyway after a power cut so it it is likely to occur from time to time anyway.

Peter

Hello!

The switches reflect the system configuration

• there is a gas boiler attached 
• there is a Domestic Hot Water tank 300 liters (too small for my girls :))
• on Heating/Cooling there is a buffer tank of 50 l calculated by the installer and seems ok for my house.
• Model ERSC-VM2D - first on the list at point SW5 + internal heater 2kW

Regarding the reading of the switches, the HP was restarted several times (complete power cut off) since the DIP switches were set up. 

Ok. It looks like we've exhausted the easy wins. I'll need to read the other document and will get back to you soon.

So, in this manual

https://torn-climatizare.ro/wp-content/uploads/2018/07/Manual-de-instalare-Mitsubishi-Electric-ERSC-VM2D.pdf

Starting from page 28 is the system setup (makes a strong cup of coffee) …

On page 30 there is something I don’t understand

I’ve got to Intelligent settings/Energy Price and I get the Electricity setting but what is the Boiler setting?

Can you also tell me what you have set for the others in this area?

I believe Hybrid settings should be set to Priority/Ambient/Cost/CO2

Thanks

Peter

The next thing I have discovered is this setting

Page 19, you need Boiler selected according to this

​@Peter E : Yep, I know the setting but it requires an external relay to trigger gas Boiler switch on/off, regardless of the Intelligent settings in HA.

It is an option if I can reinvent the hot water :)) and rewrite all the logic outside HP:

• calculate the COP curves (although they can only be guessed from specs) outside the HP intelligent settings - e.g in Home assistant or in ESP microcontroller
• evaluate cost /kWh heat and decide when to switch + margins to avoid frequent switching on borderline …
• Program another ESP8266 or ESP01 + relay to fulfil this function. I have a few of them already connected to different devices
• I could also force some improvements via Smart Grid functions - to heat DHW or raise water temperature when the energy is cheaper or from PV (autumn / spring)
• i exclude any option where I will trigger manualle any switch - I am full of automations in my house and any additiona long term maintenance will make me serve the automation not the other way around

But these are workarounds. I am able to program the microcontrollers to do the job but as a last resort.

The challenge now is to make it work as it was designed by the manufacturer.

Thank you!