How do I set Ecodan Heating

Scoobnut

A year ago we had a Mitsubishi Ecodan system installed under the warmer homes scheme, replacing a soild fuel boiler. While the elecrtic bill went up we managed. Untill now. My bill in January was 950 with my 150 discount. April it was 1,140 and we'd hardly used the heating and gone back to peat. My husband is retired and I am disabled, my electric bills are over twice what I paid before instalation. We cant keep this up. I have set the water on a schedual running from 8am till 6pm as it seemed pointless to heat the water at night when no-one used it. Will this work and can I set a schedual for the heating dropping the temp from 21 to 18. we have managed to stop the heating coming on by keeping the thermostat in the living room as the heat from the stove keeps it from coming. We live in the Western Isles and dont get temps below 0 much but do get cool summers wind and rain. When the wind hits the poor heating system ends up on all the time trying to keep the house warm. I can't ask the fitters that installed it as the fella that set up the system wasn't even sure he'd done it right and the fella that came to service it had to ring another to talk him through it. How do set it to run efficiantly and can I actually switch the heating off and just keep the water on.

Thank you,

Elsa

Mstty

Hello Elsa,

We have a Mitsubishi Ecodan and at the moment with the two of us the differences in your setup is the hot water is on for 45 mins a day so that we can both have a shower and there's enough for a bit of washing up and hand washing etc.

Next thing is our heating us completely off and not required.

I would start with those two settings on the Ecodan panel with the scheduler.

There are other good links in this forum into how to run an air source heat pump I will dig some out.

Matt

Mstty

Here is something to read, it's something I have taken some bits from to look at this winter but as my install was part of the build it will be different than the retro fitted systems. 

The retro fit systems will use more power but there are some good hints and tips so grab a cup of your favourite and have a read

https://forums.moneysavingexpert.com/discussion/6240076/i-bought-a-heat-pump/p1

Reed_Richards

@Scoobnut, did you get new radiators when the Ecodan system was installed?  Did you get a new hot water cylinder also?

I replaced an oil boiler with an ASHP similar to your Ecodan.  My electricity bill increased hugely but my oil bill dropped to zero so overall I was paying a similar amount for heating.  You should expect a much larger electricity bill but that should be offset by paying much less for the solid fuel (peat?) that you were using before.

To get a heat pump to work efficiently they should be installed by someone who knows what they are doing and run with the correct settings.  For example, your heat pump will have a feature known as Weather Compensation which will improve the efficiency (so reduce the running costs) if set up correctly and switched on.  Is there anyone local to you that knows enough about heat pumps to check if it has been set up correctly?   

ProDave

You cannot compare electric heating, even with a heat pump, with burning peat.  Peat is usually free, you just put in the effort to cut it , stack it to dry, then bring it home.  You will never get cheaper than that.

Your heating should be off now.  I measure my usage of the heat pump weekly, and in the last 2 weeks we have used 13kWh per week heating the hot water,  that's about £3.50 per week to heat the hot water, or 50p per day.

Reed_Richards

ProDave said:

...Your heating should be off now. ...

Mine is not; this depends entirely on where you live and your tolerance for cold.  Last week I was away and turned the heating off but my controller maintained a record of the inside temperature.  During that time the indoor temperature varied between 16.5 C and 18 C, about 17 C on average.  That's not warm enough for me or my spouse; we keep the house at about 19.5 C, averaged over 24 hours.         

matelodave

Do you really need to heat your water all day?

Mine runs for less than a hour a day and heats the water to 45 degrees (it sterilises once a week to 60) and that gives us all the hot water we need. As others have said the heating is effectively off now we are in the warmer months but, it will come on if the house temperature. drops below the thermostat settings.

Reed_Richards has probably hit the nail on the head, they really aren't just a drop-in replacement for an old boiler. The whole system has to be upgraded (radiators, tank and possibly pipework) to suit the different characteristics of a heatpump otherwise it's unlikely to produce an efficient system. It's also the reason most people complain about poor performance and high running costs.
They need to be set up correctly by someone who knows what they are doing and most importantly you should understand how they work and how to operate the system properly. 

Heatpumps may be energy efficient but as they use peak rate electricity, which is more expensive than almost anything else, then it doesn't necessarily make them cheap to run.

Reed_Richards

I cannot understand the fixation that you see a lot here with how long you heat your hot water cylinder.  If it is set to be on for 24 hours then it will only actually be heated when the water temperature drops below the set temperature by several degrees.   If you heat your water cylinder shortly before you use most hot water and, say, the water in the cylinder drops in temperature by 20 C in 24 hours then the average cylinder temperature would be 10 C lower so you would only lose, say, 75% of the heat you would otherwise have done.  But you could achieve the same result by setting the cylinder temperature 10 C lower.

Now @matelodave is smart and has done both.  But people here often hold the hot water heating running time to be important yet rarely mention the equal importance of the set temperature.       

ProDave

Reed_Richards said:

ProDave said:

...Your heating should be off now. ...

Mine is not; this depends entirely on where you live and your tolerance for cold.  Last week I was away and turned the heating off but my controller maintained a record of the inside temperature.  During that time the indoor temperature varied between 16.5 C and 18 C, about 17 C on average.  That's not warm enough for me or my spouse; we keep the house at about 19.5 C, averaged over 24 hours.         

Eastern highlands here, about 20 miles north of Inverness, in a sheltered glen away from the  influence of the sea temperature so it can get very cold here.  the last week has been perhaps an average of 10 degrees outside but still maintaining 21 degrees inside with no heating.

This points to yours being a poorly insulated house which is not the best candidate got a heat pump.

Mstty

ProDave said:

Reed_Richards said:

ProDave said:

...Your heating should be off now. ...

Mine is not; this depends entirely on where you live and your tolerance for cold.  Last week I was away and turned the heating off but my controller maintained a record of the inside temperature.  During that time the indoor temperature varied between 16.5 C and 18 C, about 17 C on average.  That's not warm enough for me or my spouse; we keep the house at about 19.5 C, averaged over 24 hours.         

Eastern highlands here, about 20 miles north of Inverness, in a sheltered glen away from the  influence of the sea temperature so it can get very cold here.  the last week has been perhaps an average of 10 degrees outside but still maintaining 21 degrees inside with no heating.

This points to yours being a poorly insulated house which is not the best candidate got a heat pump.

I tried pointing this out in the past when discussing outside temperature. They were insistent temperature matched outside so I pointed to insulation and bad heat loss as they would have lots of solar gain..........

Reed_Richards

ProDave said:

This points to yours being a poorly insulated house which is not the best candidate got a heat pump.

Not necessarily.  Roofs and walls will get heated by the sun but the better insulated they are the less the interior of the house will benefit.  So you are mostly relying on solar gain through windows in a well-insulated house.  Maybe I don't have enough south-facing windows?  The average outside temperature appears to have been about 12 C when my inside average was about 17 C so there is certainly solar gain, just not enough.

A poorly-insulated house is not the best candidate for any form of heating that costs you money, heat pumps are no better or worse in this respect as far as running costs go.