Mitsubishi ecodan Heatpump Boiler

[sinewave]

The reason I was look at the ecodan is there is no Gas where I live and Oil has gone through the roof. I'm going to replaceing the whole central heating and water system anyway so now is a good time for a change.

However there seems to be a problem in that I need the 14kW unit which Mitsi are still developing so it looks like I'll have to look at alternatives as I need it sorted really before the end of summer.

Any other ideas?

[frank]

The reason I was look at the ecodan is there is no Gas where I live and Oil has gone through the roof. I'm going to replaceing the whole central heating and water system anyway so now is a good time for a change.

However there seems to be a problem in that I need the 14kW unit which Mitsi are still developing so it looks like I'll have to look at alternatives as I need it sorted really before the end of summer.

Any other ideas?

Does your estimate of 14kw include the hot water?

the Daikin Altherma might be of interest as these go up to 12 kw. Do your heat loss calcs based on 40w/m2, this ignores the hot water storage but it is how to size for the Altherma.
The one I've just installed seems to be the dogs dangly bits and I wish now that I hadn't just replaced my old gas fired boiler with a new combi unit.

[sinewave]

To be honest Frank I've not sized it my self, I got Mitsi Tech Engineer out from Manchester to have a look.

They currently have the 9kW unit installed at their MD's 3/4 Deb Gaff Down Souff and it does the Heating & the Water with a pressurised Heat Store.

Yes the flow temps are lower at a max of 55 degrees which means oversized Rads or Underfloor heating.

Not heard of the Daikin alternative will have to have a look but to be honest I'm becomming a bit dispondent with the whole idea and may just plumb for LPG anyway!

[sinewave]

Anyone else got any experience with the Daikin unit or Mitsi?

[Budicus]

Do your heat loss calcs based on 40w/m2, [/quote]

If you were doing you heat loss calcs based on 40w/m2 I would be worried...That would exceed new build regulations by 5w/m2, and that is as rare as hens teeth in a retrofit and very rare in a new build...

Sorry to say it but if you do it on 40w/m2 your heat pump will be too small and your running costs would be much higher than they should be.

[frank]

Got to agree.

Since I've been on the Altherma training course, I learned that it's now based on 50w/m2.

[Daikin=Overated]

Do your heat loss calcs based on 40w/m2,

If you were doing you heat loss calcs based on 40w/m2 I would be worried...That would exceed new build regulations by 5w/m2, and that is as rare as hens teeth in a retrofit and very rare in a new build...

Sorry to say it but if you do it on 40w/m2 your heat pump will be too small and your running costs would be much higher than they should be.[/quote]
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Correct. The latest Daikin advice is based on 50w per m2!!

I have attended both training courses for the Ecodan and Altherma. My username aside the Daikin is a far more versatile product with the slight upper hand on the tried and tested front too!

The other disadvantage to EcoDan is that the outdoor unit is a packaged unit that couples to hot/cold water supply pipes only-no interconnecting refrigeration pipes to indoor unit as with Altherma. Mitsubishi state that a qualified plumber to GNVQ level three or some crap must have commissioned this side of the system. This presents warranty issues etc should us A/C chaps get on board. That personally turned me off the product-not to mention that the indoor/outdoor unit is massive!!

Altherma has cooling options, a dedicated hydro indoor box (size of a compact combi boiler)interconnected via refrigeration copper piping. And the water tanks have solar interconnectivity options (again these are more slimline than the EcoDans water storage).

You must have a safe handling certificate and have attended the Altherma training course to purchase this kit through Daikin I was recently advised!

I'm also fitting my first Altherma system to a 4 bed in Surrey. We're ditching the gas supply there altogether making savings of ££££'s. I shall do my best to keep you posted.

[falkirk heat]

The reason I was look at the ecodan is there is no Gas where I live and Oil has gone through the roof. I'm going to replaceing the whole central heating and water system anyway so now is a good time for a change.

However there seems to be a problem in that I need the 14kW unit which Mitsi are still developing so it looks like I'll have to look at alternatives as I need it sorted really before the end of summer.

Any other ideas?

i have installed both mitsibushi and daikin prefer daikin mitsibushi unit is now developed i have installed three

[Pollardspark]

Hi

I installed a Mitsibushi Ecodan air source heat pump system last August. I have had a miserable winter.

First the system does work, heat is collected from the outside, even at sub-zero. However, the good news ends there. It is a new technology and a chose a local installer from those approved by Mitsibushi on a list they supplied. The dealer also featured in their publicity brochure and video. I am a pensioner and have no heating knowledge and had to rely on the installer, particularly with the Mitsibushi recommendation behind him.

I now appreciate how important it is that heat loss calculations are carried out on the property for a retro fit. It has become very clear in hindsight, that this was not done and that the heat pump is under size. My house is well protected with cavity wall, double glazing and well insulated loft, but the installer failed to do the basics, although I gave him all the room sizes when he surveyed the property. The heat runs through the system (assuming a correct size Ecodan) at 55 degrees, instead of around 70 for a oil/gas installation. Therefore, all radiators have to be changed to increase the surface area by about a third.

In addition to an undersized system - the warmest the lounge has got through the winter is 17, on coldest days 14 - the Ecodan comes packaged with a Gledhill tank. This has been nothing but a problem. It is difficult to program times, but more importantly we have had trouble with elements of it, including needing new printed circuit boards and being without any heating or hot water for a week while they were replaced.

My advice, is look very carefully, if it is a retro fit. Check out the installer (I thought I had since Mitsibushi featured them so strongly) and be very careful to look close at the unit which comes with the air pump. This unit drives the whole process and is the 'brains' of the system. Additionally, since it will become a sealed system under mains pressure, you have to be very sure of all joints etc in the existing system – we found this out the hard way!

Despite visits from the installer and Mitsubishi (supposedly their top man on Ecodan/Gledhill) no significant improvements have been achieved – though some tinkering with the system has gone on to very minor effect. My wife and I have suffered chest colds all winter and have been ill, we are now seriously looking at facing the cost of replacing the Ecodan with oil during the summer. We cannot have another winter like the last.

[back2space]

Hi

we are now seriously looking at facing the cost of replacing the Ecodan with oil during the summer. We cannot have another winter like the last.

before you rip it out and install a new system consider if you replace the radiators with fan coil units. These have a radiator similar to a car radiator that blows air through to heat the room up. This would be perfect for the temperature of the water flowign through. Plus you would have cooling in summer also I think.

Because a radiator doesnt move air the room temp slowly increases and if the rads havent been oversized for the rooms then this is why you cannot raise the temps.

Cheaper option is to replace the rads with fan assisted units.

[Gary]

before you rip it out and install a new system consider if you replace the radiators with fan coil units. These have a radiator similar to a car radiator that blows air through to heat the room up. This would be perfect for the temperature of the water flowign through. Plus you would have cooling in summer also I think.

Because a radiator doesnt move air the room temp slowly increases and if the rads havent been oversized for the rooms then this is why you cannot raise the temps.

Cheaper option is to replace the rads with fan assisted units.

I totally agree with this analysis. The fact that the system is able to maintain 55C water while the rooms are underheated tells us that the problem lies in between the rooms and the water. In other words, the radiators are unable to transfer sufficient heat from the water to the rooms.

[Karl Hofmann]

Any heating engineer worth his salt will tell you that the rads have to be oversized.. Roughly by 30%. Fan coils where as good are noisy and high maintainance. Underfloor is ideal for heat pumps.

As for Gledhill heat banks... Good riddance to bad rubbish, I've never met a Gledhill sludge bucket that didn't leak... A nice idea but badly made..

[sweeney948]

Hi there we have experienced the same problems could you PM me please