MCZ Musa Hydro 15kw - thoughts

Swampy2

I've just had a clarification from Ofgem re Rhi payments

"In regards to your boiler already accredited to the scheme, as it currently stands your payments will not be withheld....... The safety issue currently relate to new applications of these models"

cancunia

Swampy,

That's the first piece of good news in this whole sorry affair. Thanks for sharing it.

[Deleted User]

we had a bit of a smoke problem with our flue yesterday and the local mcz trained engineer came out and dismantled the flue and re-assembled it. He was very reassuring about the hydro 15 and about the reason for the glass blowing out. I feel very safe now and very happy about your kind sharing of information swampy. Next step now is to face the audit next week, we have the paperwork ready and what will be will be

Burnardo

Hi everyone, new to the forum and just noticed this thread.
We had our Musa Hydro 22kw installed with a 500l store last April/May, my impressions so far are as follows:
We've had no problems, breakdowns etc at all. I was concerned about the product warning as the glass is the same hight as our sons head! My installer looked into the product warning, he says it was a few poor installations, and people who didn't clean out the 'hearth' regularly leading to a build up of unburned gasses, and explosion when they did ignite. So long as the installation is correct and the machine is cleaned as per directions, there should be no problems.
We absolutely love our machine. Good Italian design from the outside, really makes the kitchen (where it's installed) a warm homely place, provides lots of hot water for the radiators and baths etc, dries out washing when the clothes horse is put in front of it.
During the summer we were getting through one 15kg bag per 7-10 days, now more like a bag per day, but our local supplier (lives in our village) charges £120/half ton, so our annual bill should be about the same as if we had a gas boiler.
Our total install cost just shy of £12,000, a LOT of money and major investment, but as the old oil burner was 70% efficient, leaked oil into the kitchen, and occasionally exploded on fire up(!) we had no option. We wanted to reduce our carbon footprint as well.
We have been on the RHI scheme for a few months, and have received our first payment, so if things go as planned we'll recoup our investment in under five years.
Our installers business is less than 5 miles away, is long established, and knowledgeable, I have a lot of confidence in them.
The only foreseeable problem is that I can handle our 15kg bags of pellets now, but maybe not in 15 years time (early 50's now), maybe organise a hopper and screw arrangement as time goes on.
So overall; looks great, does a great job heating us and house, good pellet price and installer round here (S Wales), good RHI payments means a good return on investment.
Everyone's situation is different, and we've only been running our system for 6 months or so, but so far we are very happy with it.

Silent_Dancer

As of today the MCZ Hydro is still suspended by MCS.http://www.greenbooklive.com/page.jsp?id=236

Burnardo's post is interesting as there is now an admission by the product suppliers that it is not just an installation problem but due to explosive ignition. I am not sure of the standards for pellet boilers but I'd guess that there are tests to ensure that the boiler is safe if explosive ignition occurs.

Burnardo states that it his old oil boiler suffered from explosive ignition. Clearly it was well designed and built as it did not disintegrate when such an event occurred.

cancunia

On the Specflue home page, just above the info about Musa stoves there is an ad for Haas & Sohn draught regulators. The one in the picture has a flap that opens in case of explosions in the firebox. From reading the install instructions, this seems to be something often fitted to oil burning stoves.

When Specflue came to sort out my igniter problem, they were very keen to measure the flue draft and check the burning efficiency, my guess is that the flue installation is key to safe operation and may not have been emphasised enough in the past.

The Musa stoves are sold througout Europe, it is odd that this has not come to light before.


Kittie - thanks, for the message, I tried to reply but for some reason was unable to send.

[Deleted User]

cancunia, I tend to disable pms as I get lots of messages from other boards. Ask me here if you like, it is important that we are open re the mcz. I believe that it is very important to support each other about a major potential safety hazard

I feel a responsibility to get back here re the 22. My engineer explained the problem and the cause is indeed due to a build up of explosive gases pre ignition. The solution will likely be a pressure release valve via the flue but that is in process of testing

The 22 is a powerful stove
http://www.renewablesnow.co.uk/products/mcz/mcz-hydro-stoves.shtm

The gases were not being exhausted quickly enough so building up a lot of pressure and upon igniting blew the door off

In all honesty if we had a 22, we would not be using it without the future fix. It is a design fault

The 15 is safe, although involved in testing but there are aspects that we are not liking such as the quick build up of creosote so rendering it less efficient

We are retired and have savings and now seriously looking at getting a different stove next summer. Our engineer recommended a firewin from windhager, which would be more suitable for our eco house anyway. He is not a winhager partner so had nothing to gain from the suggestion, just a very honest methodical guy. He has his own business, getting bigger all the time and at no stage in his career did he recommend a 22 to anyone as he said it was oversized and had this particular design fault from the start. He said it was always unsafe

cancunia

Kittie,

I wonder if the tar / creosote problem you have has something to do with your wood pellets? My 15kw stove has no problems with tar buildup in the area inside the door. fwiw, mine uses 'Brites'

On the more general subject of this thread, while I am in no way 100% pleased with the service I've received, I do think that the MCZ stoves offer a good mid range product. The problem seems to have come from a combination of factors, mainly around the guidance given on proper installation which seems particularly critical on the higher performance 22kw stoves. From what I read somewhere else, the installation guidelines have now been revised to emphasise correct flue installation.
Before I bought the MCZ stove, I had some discussions with Windhager UK, who were less than forthcoming about some aspects of their stoves. I think that the Windhager products are good, just the support that I got was bad, just as we see in some aspects of MCZ in the UK.

Looking at the numbers again, 4 reported incidents out of how many thousands? There is a good reason why gas boilers need to be installed by registered engineers, perhaps it is time for a similar thing for biomass? When the stoves are operating at over 90% efficiency, they are in effect practically gas burning appliances.
Personally, I am glad that MCS have taken prompt action to suspend registration of new installations pending investigation and also from what Specflue told me that existing installlations will be reviewed. I just hope that it will be resolved quickly, positively and end up with a better service for us consumers. Putting stickers on boilers and walking away helps no one.

[Deleted User]

my long post vanished, doh

We use brites and sometimes verdo. We had a difficult time re gettng mcz qualified engineers for servicing. Installer went bust, second company went bust but we have been fortunate and found one only a few miles away. They install stoves/boilers/air source and are mcs reg and green deal assessors. He said that 15kw is too high for this house.

I believe the tar build up is down to not burning hot enough for long enough, we only need 1 tonne a year, hence the problem. We are not diving into getting an expensive new stove but will be having a look before long and am hoping that windhager would work with our engineers but we`ll see as we do want to comply properly for the 5 year guarantee

Mcz is good, in the right circumstance but I think was wrong for us here. Last night for example, got to 22 degrees in the living area whilst the top of the hot water tank was only 45

Re the numbers, yes 4 is low but people should be made aware so that they are vigilant

candyflossco

Hi , new to this thread , was wondering has anyone had faulty pellets ? we have a hooper system, last year we got pellets from balcas and there was a lump of wood that got stuck in the auger ( they paid for this to be fixed ) this time round pellets seem to be like dust , and now have caused the motor to burn out , was just wondering has anyone else had any issues , thanks