Ecodan Assistance Required

Yuccaman

Hi,

We've recently had an Ecodan 8.5KW Heat Pump installed alongside a 180L tank and new rads throughout. The property is housing association which is good as we haven't paid for the install, but bad as I'm unsure of the standard of the job and whether things have been configured properly !!!!

I've noticed some weird behavior and after trying to find and read what I can about the various bits of kit, thought I would see if anyone here can assist with the stuff that is happening:

We have a basic set-up, Ecodan and 180L Tank (with Immersion). No booster heater. Single room thermostat to control desired temp. Drayton timer left permanently on in Heating Mode with 3 separate windows for Hot Water heating. I wasn't privy to the exact settings entered into controller but when in Hot Water Mode, the desired Temp shows as 58 degree for Ecodan Heating and 65 degrees for Immersion. In Heating ECO mode, desired flow temp is 55 degree.... Apparently, the installer decreed these were the best settings for all properties

The weird (or simply misconfigured stuff) is:

1 - The Immersion is activated each time the Ecodan heats up the water to 58 degrees. I *assume* this is because the relevant dip switches in the FTC have been set to this, instead of every 15 or 150 Hot Water cycles - Is that right ?

2 - Sometimes, the FTC switches the Ecodan Off and lets the Immersion heat up the water well BEFORE the tank gets to 58 degrees. I have read that the FTC will activate the 'Electric Heater' (which I assume is the Immersion and not a Booster Heater that we don't have !!!) if it detects the Tank Temperature doesn't rise by a degree after 10 minutes... Should it do this if we don't have a Booster Heater ?

3 - I have also read that the FTC should only activate the Ecodan for heating Hot Water if the Tank Temp is lower than either 10 or 20 degrees that the target temp. Is that the case as tonight, when the Hot Water Timer activated, the tank temp was 54 degree and yet the FTC switched the Ecodan on to try and heat the water. This happens quite often....

I further assume it takes a bit of time for the Ecodan to get the water in its system heated enough to heat the water in the tank as after 10 minutes, the tank temp remained at 54 degrees and so the FTC switched the Ecodan off and the Immersion on to try and heat the water. I got the FTC back into Normal Hot Water mode and the Ecodan fired up again and this time heated the water to 58 degrees after another 15 minutes, and then the Immersion kicked in AGAIN to sanitise

4 - The Radiator temperature seems a little strange... If we choose a target temp of 20 degrees on the wall thermostat, every rad gets VERY hot. Choose a target tempt of 18 degrees and the rads only get tepid.... In my ignorance, this maybe cos the house temp is hovering around 18 degrees normally and hence there is not a huge need for heating if we want an 18 degree temp... I am kind of hoping for a very cold day where the heating is left at either 18 degrees or 20 degrees for the day to see how warm the house is kept.

5 (and lastly - for now) - We appear to be using a hell of a lot of electric, considering the heating is not switched on much at the moment.... Admittedly, our house lacks Cavity Wall Insulation from what I'm told. We've been using about 20-30 Units a day when having the heating on for say 3-4 hours at 20 degrees. When using Hot Water Only, it varies from 4-6 units per day so that's 14-24 units on part-time heating !!!!

We do tend to turn the thermostat down to 15 degrees if we don't want any heating, even though I have suggested it may be better to leave it at 18 degrees in the day, as I assume it takes time for the Ecodan to heat the water going through the rads from very cold and hence if you switch it on, then back to 15 degrees for a few hours and then back on again, you're are forcing it to do more work each time to heat rad water from cold as opposed to what it would do to keep the temp ticking over - No idea if that's right or a load of cobblers though !!!!

Again, I am half hoping for a cold day to see how much electric is used with the heating left constantly on at 18 or 20 degrees....

Apologies for the huge amount of questions and I hope I can get things sorted to get a warm house, hot water and manageable bills.

Even with all the crap above, it's far better that the solid fuel system we had previously, albeit current expectations for winter bills mean it may well be a lot dearer !!!!

Cheers,

Rob

albyota

Hi Rob, it seems as if the installer needs to re-visit to sort it all out.....properly, there should be a ECO/BOOST switch and if set on this it will use the external weather compensation sensor. As for the immersion heater, this should be set to only come on either...once a week or after so many compressor cycles, this is adjusted by flicking dip switches in the FTC. The most important thing is to set the hot water runs when heating is not required, i.e. ealy morning/early afternoon/evening.

Yuccaman

Cheers, I have been waiting for the installers to contact me purely about the Immersion coming on each Hot Water Cycle but I will mention the rest to them as well... I doubt they will be prepared to fit anything such as a Eco/Boost switch though.... I assume with this, the Heating would switch between Heating and Heating ECO ? Our Heating is always Heating Eco (Well, that's the display on the PAR Controller when the heating is on anyway !!!!!)

albyota

Yuccaman, the ECO/BOOST switch is simply a 2 way switch,
Heat Eco-Heat J2, Short Pins 1-3 = Eco-heat , Short Pins 1-2 = Boost Heat

samtheman1k

1: the hot water need to be heated to above 60deg for building regulations. As your temperature is set to 65deg, then the immersion will come on to reach that temperature everytime the water is turned on. The max temperature from the ecodan is 55deg iirc, thus the immersion will always come on.

2:as before, the max temperature from the ecodan is 55deg

3: tank temp = 54deg, desired temp = 65deg, difference = 11deg which is greater than 10.

4: it sounds like that the thermostat is constantly switching between just above and just below 18deg, thus constantly switching the heating (ecodan) on and off, thus the water will never get hot. Is the thermostat near a radiator or a window?

5: IIRC, the ecodan uses about 2.5kW, plus the electric boost (which is probably 3kW). 4 hrs at 2.5kW is 10kwH (units). I think in your normal 58deg mode, it must use the electric boost, thus 4hrs at 5.5kW is 22kWH (units). Try running in eco mode (that doesn't use the electric boost).

The ecomode seems to only affect the heating from your post, not the HW.