Posted by: @derek-m

↑

Posted by: @jasper01

↑

 

 

 

I do believe that for the Ecodan controller to accept changes in settings in the installer/service mode, it is necessary to shut it down and restart, but maybe some Ecodan owners can confirm this requirement.

That is correct.  It is necessary on the Ecodan to press "YES" to shutdown in order to access the service mode.  That option scared the life out of me when I came up against this same issue.  It was pointed out to me by another Ecodan owner on here.

Posted by: @jasper01

↑

@sunandair right so I was able to access the thermister reading - lowest figure was 9 degree c (Th7)

DHW is 55 36 set temp (FLOW)

 

 

hi Sorry for the overload of information. It also seems a few people were writing to you at the same time.  Also thanks for extra info eg UFHeating. 

Well it’s great that you’ve managed to find the above information. 
it appears from this information your live outside temperature last night was 9degC and that your compensation curve is set to achieve a flow temperature of 36 degC when it’s 9C outside. So now ask yourself how comfortable was your home at that flow temperature?

(Also, Now you know how to find the set flow temperature by pressing the i button you can check it when it’s colder outside or at any time.)

The next thing to learn is how to temporarily change the flow temperature if you want the flow temperature slightly warmer. To do this go to the main screen and press  the button to light up the screen. Then press the + button or the - button. This will raise or lower the weather compensation curve by one degree. 

why would you do this? If you check the flow temperature using the i button it will have been changed to a new temperature. So you can alter the temperature of your home by changing the flow temperature and that will mean the Heat Pump is working at its most efficient setting instead of over heating and then switching off. 

once the room temperature is right by say adjusting the + button you will now have a new flow temperature you can take a reading of the new flow temperature (using the i button) then check what the outside temperature is. 

Each time you reach the perfect room temperature you know that the flow temp matches the outside temperature and that is another dot on the ideal weather compensation curve.  

I hope this makes a bit more sense. 
Once you have a few dots on a temperature graph you might then know if your existing curve is right or if it needs adjusting. 

One thing I find very curious about WC, is how a sudden drop  in outside temperature impacts the indoor temp...?

A well insulated house will retain heat for a period of time, so if for example the outdoor temp has been 15C during the day but then it drops to -5C overnight, does the WC change the LWC instantly? I would imagine this would leave the house being too warm, because the fabric of the house has the thermal energy stored it wouldn't need the increase in LWC straight away... would it??

@squeakysim I guess, and it is a guess, that this is where the Auto adaptive mode is a refinement of weather compensation. 

I was discussing with a Mitsubishi help desk engineer yesterday how it works. He confirmed that Auto Adaptive Room Temp mode actually uses the weather compensation curve as it’s base line of information. It is set to also monitor a specific room thermostat relative to the outside temperature. 

When the mode is first set up apparently it learns how quickly the room temperature is reached purely from the flow temp of the weather compensation curve. then apparently it starts to adjust the flow temperature (modulates) as it gets closer to the set room thermostat temp. 

So I would think it would make sense to ensure the chosen weather compensation curve is corrected and as accurate as possible before entering into the world of auto adaptation.

For large gradients in temperature like you’re suggesting I think it can also accelerate flow temp rise as well as slow it down. 

The problem is it takes some time to fine tune the process and there’s a few other parameters to understand and adjust…

Are you using a Mitsubishi system

That description by @sunandair accords with what I experience with my system. Mitsubishi 14kW FTC5 with wireless room thermostat/controller which has been running under Auto Adaptive since installation in 2019.  If the outside temperature is rising then the system holds off increasing the indoor temperature even although the conditions are met by the wireless controller setting, at least until it sees what the inside temperature is doing. The same is true in reverse that if the outside temp suddenly starts to fall steeply the system starts to heat in anticipation of the inside temps falling.  It allows it to make good use of any solar gain when the sun comes out and doesn't seem to get caught out when the polar blast suddenly appears.

My installer did say that the outside temp is measured by sensor on the rear of the outdoor unit and can occasionally get caught out by heat reflection from the harled wall that the unit is installed in front of. Not an issue for me at present given the weather conditions.

Posted by: @sunandair

↑

Posted by: @jasper01

↑

@sunandair right so I was able to access the thermister reading - lowest figure was 9 degree c (Th7)

DHW is 55 36 set temp (FLOW)

 

 

hi Sorry for the overload of information. It also seems a few people were writing to you at the same time.  Also thanks for extra info eg UFHeating. 

Well it’s great that you’ve managed to find the above information. 
it appears from this information your live outside temperature last night was 9degC and that your compensation curve is set to achieve a flow temperature of 36 degC when it’s 9C outside. So now ask yourself how comfortable was your home at that flow temperature?

(Also, Now you know how to find the set flow temperature by pressing the i button you can check it when it’s colder outside or at any time.)

The next thing to learn is how to temporarily change the flow temperature if you want the flow temperature slightly warmer. To do this go to the main screen and press  the button to light up the screen. Then press the + button or the - button. This will raise or lower the weather compensation curve by one degree. 

why would you do this? If you check the flow temperature using the i button it will have been changed to a new temperature. So you can alter the temperature of your home by changing the flow temperature and that will mean the Heat Pump is working at its most efficient setting instead of over heating and then switching off. 

once the room temperature is right by say adjusting the + button you will now have a new flow temperature you can take a reading of the new flow temperature (using the i button) then check what the outside temperature is. 

Each time you reach the perfect room temperature you know that the flow temp matches the outside temperature and that is another dot on the ideal weather compensation curve.  

I hope this makes a bit more sense. 
Once you have a few dots on a temperature graph you might then know if your existing curve is right or if it needs adjusting. 

 

I think that you will find that the above technique would work fine if the only influence was the outside air temperature, but takes no account of other factors.

Many thanks everyone.

Some of it went in, a lot didn't, which I feel bad about as some of you have taken a lot of trouble to explain.

So, I was struggling with the thermostats last night. I'm constantly up and down adjusting them. I tend to be turning them down more often than up (saving electricity); although the house isn't 'toasty'. I'm running it at acceptable levels (wearing a jumper).

Last night, the temperature seemed good, but then just when I t

hink it's warm enough and want it to stay like that, one or other thermostat pops on...and then off again. ( I know that's the point, but they seem sensitive one minute and then not the next i.e. don't come on when it feels cold ).

But, because of this, I put the system back onto timer over-night because it was plenty warm enough (and the UFH seems to hold a long time, so that's at least a good thing); plus, and I didn't want it going on and off all night (needless expenditure).

However, I also wanted it warmer in the morning.

In other words, the thermostats just seem to be a law unto themselves. I'm certain the relationship between the them and the heat pump is skewed - as others have suggested.

So, that's another thing. If I want it cooler over night, ( assuming the system is running on constant), then I can't have it warmer in the morning without getting out of bed early and adjusting the thermostats?! How does this work if it's on constant? 

I have attached some photo's so they might clarify a few things.

I'm a bit worried about going into any other settings by shutting down the system. Just in case; although it sounds straight forward. If I mess it up, the H/A will go nuts.

I've hounded them about it since August.

So, these settings on the curve; will they suffice? What about if it gets cold again? What do I need to do then?

I've just put it back on constant again. We're in credit with Octopus anyway, so I might as well use this time to wrestle with it I suppose. It's now on, but no thermostats have clicked on yet, the house feels warm (ish) - not toasty, but fine for daytime. I'm a bit cold sat working at my desk (should be working - achem !), but I'll just put a jumper on. It's warm outside at 12 degrees. 

All I'm going to have to do at the moment is get by with it, because I really can't get my head around it all. I'm not up to taking readings and doing maths - maths is my absolute worst subject. I do really need the thing to just operate while I blithely ignore it! I'm no 'techi' by a very, very long shot. 

That said, I am fully prepared to pay someone to come and do it for me. I am currently making enquiries with a local expert. That'll be bye bye to £250 quid no doubt. Gulp.

Posted by: @squeakysim

↑

One thing I find very curious about WC, is how a sudden drop  in outside temperature impacts the indoor temp...?

A well insulated house will retain heat for a period of time, so if for example the outdoor temp has been 15C during the day but then it drops to -5C overnight, does the WC change the LWC instantly? I would imagine this would leave the house being too warm, because the fabric of the house has the thermal energy stored it wouldn't need the increase in LWC straight away... would it??

This is one of the reasons why weather compensation cannot provide perfectly accurate control of the indoor temperature, but because the change in outside air temperature is not immediate and can take quite a few hours, the temperature difference balances out to a great extent. As the outside air temperature falls, the DeltaT between indoor and outside increases, so the rate of heat loss increases, which in turn balances the additional heat energy being supplied. A further factor is that it also takes time for the extra heat energy provided by the higher LWT to actual warm the air within the home, which again tends to balance the affect.

@jasper01 ...I am new to the forum but joined as like you I want to fine tune and understand more about my Ecodan system.l have had mine on auto adaptation since installation 4 years ago and I monitor the energy info off the controller....I have seen a gradual reduction in the cop and decided to look at WC Instead...I have been playing around for a while although not yet experienced the cold end of the. Curve but have mine set at 25 @15c and 45@-2c and with the system running 24/7 every room has all trvs fully open and are at comfortable temperatures..... looking at your screenshot of your curve you should be having a flow temp of around 35cand would expect you to be really warm....I am currently running at 29c at 9c outside......it looks like you're heating is showing that it is on the schedule timer, I think this will not help your situation and would let it run constant so the rooms heat up any thermal mass...mine seems to cost a little bit more and still only getting a cop of 2 but I have some solid walls so going to struggle....

My problem is I seem okay with the WC and curve settings but from my melcloud hourly temperature report my heat pump is cycling on and off up to 6 times an hour which I would think is not great for the life of the compressor and will affect the cop also....any thoughts on this from anybody would be great as in this forum we seem to discuss the method of operating efficiency for comfort and cost but wear and tear on the unit is also a factor

As a newbie I think this is great that we can all discuss our own situations and hopefully share information that makes a difference.

Dave 

Posted by: @davew

↑

@jasper01 ...I am new to the forum but joined as like you I want to fine tune and understand more about my Ecodan system.l have had mine on auto adaptation since installation 4 years ago and I monitor the energy info off the controller....I have seen a gradual reduction in the cop and decided to look at WC Instead...I have been playing around for a while although not yet experienced the cold end of the. Curve but have mine set at 25 @15c and 45@-2c and with the system running 24/7 every room has all trvs fully open and are at comfortable temperatures..... looking at your screenshot of your curve you should be having a flow temp of around 35cand would expect you to be really warm....I am currently running at 29c at 9c outside......it looks like you're heating is showing that it is on the schedule timer, I think this will not help your situation and would let it run constant so the rooms heat up any thermal mass...mine seems to cost a little bit more and still only getting a cop of 2 but I have some solid walls so going to struggle....

My problem is I seem okay with the WC and curve settings but from my melcloud hourly temperature report my heat pump is cycling on and off up to 6 times an hour which I would think is not great for the life of the compressor and will affect the cop also....any thoughts on this from anybody would be great as in this forum we seem to discuss the method of operating efficiency for comfort and cost but wear and tear on the unit is also a factor

 

As a newbie I think this is great that we can all discuss our own situations and hopefully share information that makes a difference.

Dave 

 

Hi Dave,

Welcome to the forum.

If you have been operating your system in auto adaptation mode for 4 years, have you always experienced cycling? Was the weather compensation curve correctly adjusted when your system was commissioned?

My understanding is that when operating in auto adaptation, the system should also be using weather compensation. I would suggest that you ensure that all the controls are correctly set for auto adaptation to function correctly.

Also check the Interval Timer setting, since if this is set too low it can cause cycling. Some screen shots of your controller settings may prove useful.

@derek-m .........thanks Derek, that was quick!!

I can't say that I really ever studied the data but can't say that I noticed short cycling in Auto mode, the installer set the curve at 50@ -2C and 37@15c, wether this was correct or not I don't know?

I was never unhappy with Auto mode and used it on a schedule timer so maybe that dragged the cop down??........Unused rooms also TRV's set minimum.

The installer left it on constant so I was just lowering the setback at night on the wireless controller.

I have tried WC mode as generally on the web it seems that this is better for cop than auto...........all I have concluded so far is that on WC running constant the cop seems a bit better and house has all rooms heated...................As an engineer it just bothers me to see the unit cycling so much. (Wireless remote stat is set well above room temp so not interfering)

I wondered is this because the RWT is to close to the LWT..........if so would slowing the pump speed down help so more heat is given up through the emitters...the service settings show Pump Speed as 5.

What is the Interval timer and how do I access it on the FTC5 controller, I can send screen shots but which ideally would you like to see........Thanks again

Posted by: @davew

↑

@derek-m .........thanks Derek, that was quick!!

I can't say that I really ever studied the data but can't say that I noticed short cycling in Auto mode, the installer set the curve at 50@ -2C and 37@15c, wether this was correct or not I don't know?

I was never unhappy with Auto mode and used it on a schedule timer so maybe that dragged the cop down??........Unused rooms also TRV's set minimum.

The installer left it on constant so I was just lowering the setback at night on the wireless controller.

I have tried WC mode as generally on the web it seems that this is better for cop than auto...........all I have concluded so far is that on WC running constant the cop seems a bit better and house has all rooms heated...................As an engineer it just bothers me to see the unit cycling so much. (Wireless remote stat is set well above room temp so not interfering)

I wondered is this because the RWT is to close to the LWT..........if so would slowing the pump speed down help so more heat is given up through the emitters...the service settings show Pump Speed as 5.

What is the Interval timer and how do I access it on the FTC5 controller, I can send screen shots but which ideally would you like to see........Thanks again

The first thing that I would suggest is setting your system to operate in Weather Compensation (WC) mode with the following settings, LWT of 50C at outside temperature of -5C, and LWT of 25C at outside temperature of 20C. Ensure the offset is zero on the FTC5 and allow the indoor temperatures to stabilise.

The above gives a WC slope of 1C change in LWT for each 1C change in outside temperature. If your home is well insulated and the indoor temperature increases above the desired value then lower the cold end LWT setting from 50C to say 45C. Adjust the cold end LWT until you achieve the desired indoor temperature, but allow time for the temperatures to stabilse.

Once the WC slope is correctly adjusted I will supply the details for setting and optimising the auto adaptation. Note what happens with the cycling and system efficiency.