MCZ Musa Hydro 15kw - thoughts

Swampy2

After mine went wrong a week later the letter came. My stove was inspected by Specflue and condemned for not having a draught stabliser, mine was fitted before spec flue took over the uk rights. My installer has gone bust so I can't chase them. It ran fine for over a year them it all seemed to go wrong. Thing that did annoy me is they saw no draught stabiliser and refused to look any further.

I'm committed to heating the house on pellets but I've partly lost confidence in MCZ products, also fed up with the endless cleanIng and filling of the hopper. I'm going to have a froling boiler put in next year. Not sure what I'll do with the MCZ.

cancunia

Swampy, from what you've written it does seem that Specflue have been less than reasonable, your stove blew some seals after the pellets failed to light initially?
I cannot recall seeing anything in the MCZ or Specflue documentation that specifies or mandates the installation of a draught regulator, maybe I missed those pages. In an earlier post, you wrote that after a lot of chasing, MCZ put you in touch with someone to put your stove right, is it working again now / do you have a record of what they did?


My understanding is that purpose of the draught stabiliser (regulator) is to allow more air into the flue after the boiler when the flue draw is above a certain level, doing so manages down the amount of air being drawn through the boiler. Assuming that we're referring to the same item, I cannot see how a draught regulator can do anything but reduce the flow of air through the boiler, I don't see how it can increase air flow other than when it's closed which is the same as not having one.
Maybe I've got the wrong end of the stick, I'm not a heating engineer and maybe fitting a regulator to decrease the flow in cases where the draw is high helps the ignition process.

[Deleted User]

The compressed hot gases would have been under high pressure and they should have been released safely via a pressure release valve in the stove. A design fault and I cannot see how that would be retro fitted. The seals were the weak point, A draught regulator would not solve the problem

Swampy2

Specflue say a draft stabliser is mandatory stops the flue pulling to much air through and it burning to quickly/ hot I understand. I've since had one fitted.

Person who came out gave the stove a good clean etc running ok now not as good as before pellets are not burning right still semi solid pellets left not ash and glass turns brown very quickly.

Seems to me no one wants to be fully responsible. My installer went bust before signing it all off properly soon one will commit to fixing only ripping out and starting again. Can't blame anybody really just a bad situation. My installer bought it direct from Italy. Lots of people I've spoke to have said they probably went bust trying to fix MCZ boilers!

I'm going to get rid of it and put a more advanced boiler in with a big hopper that auto cleans itself. Hopefully someone will buy the MCZ for spares or MCZ will decide to give everyone their money back!

cancunia

Swampy, it may be worth getting the people that fitted the draught regulator back in to check the adjustments now it's had a chance to settle in. They can use a flue gas analyser to measure the boiler efficiency and check that you're getting the correct flow through under all conditions.

http://www.mcz.it/download/8901137200.pdf

I had another look through the MCZ installation book, although the section on flue design is quite large there's no mention of a flapper valve or draught reglator that I can see, nor could I find any reference to it on the Specflue website. There may be something that I missed, so if anyone gets a definitive answer from Specflue with some references, please post it.

dotherightthingnow

I had another look through the MCZ installation book, although the section on flue design is quite large there's no mention of a flapper valve or draught reglator that I can see, nor could I find any reference to it on the Specflue website.

Hoist by ones own petard ?

Swampy2

Latest on mine is the circulation pump won't turn off. Tried turning the unit off and on and resetting temp sensors as if it had overheated. It's happened before then just stopped after about three weeks on the day someone came to look at it. When I told spec flue guess what, they said it must be related to an install error!

It slowly cools my thermal store overnight I have to remember to turn it off before I go to bed and on in the morning before the heating comes on.

Burnardo

captainhindsight wrote: »

To the person who said their stove actually blew up, if specflue didn't blame the boiler but the installer what part of the installation did the blame? Did you Have a draft stabiliser fitted, was it set up correctly?

They blamed me for moving the CO alarm, and my installer for not putting a registration plate on the wall. Neither of these things were in any way connected to the boiler and could not have caused it to malfunction.

cancunia

Swampy, I came across a post about the pump a while ago. It's on a German site but you can easily use Google translate to translate the whole thread. I will paste the link in asap.

Specflue

I’m responding on behalf of Specflue to the growing number of views aired on this thread. As Head of Technical Support, I hope I can shed some light on some of the issues that have been raised.

Installing a biomass appliance requires thorough compliance with building regulations and inall cases that have been visited to date, this has not been the case, contributing to the external factors that can result in explosive ignition situations. Biomass appliances are more technical in design and nature than both gas and oil boilers and therefore the commissioning and overall design of the system is extremely important.

Specflue is assessing every installation visited to the current MIS3004 MCS biomass installation standards, Approved Doc J for the flue requirements and also PartF for ventilation, as well as best practice guidance as provided by CIBSE. If no CO alarm or data plate has been fitted, this will therefore be noted on the report as non-conformity for the homeowner’s safety, as we have a duty of care to show this. It is not intended to suggest an impact on the boiler’s performance. However these items are a requirement under building regulations and in ALL cases your installer should be fitting these for the home owner’s safety.

The incident Burnardo refers to is interesting, as the perception may be that the installation met all current standards and the installer had done a good job and therefore cannot be deemed as a contributing factor to the incident. However, the installation in question had 6 contraventions to building regulations that directly affected the wiring, ventilation and flue effectiveness of the appliance. The installation also had a further 3 items which were highlighted as not being present in line with best practice as outlined in the CIBSE best practice guide. This has had the effect of chocking the appliance and reducing the efficiency of the flue.

There was also no point for a flue gas analysis to take place or in order to balance the flue draft stabiliser and this would indicate the appliance could not have been commissioned in line with MIS3004. In addition, there was also no record of receiving any commissioning paperwork back for the appliance.

The pictures taken of this installation and the report were also forwarded to BRE and MCS. We have notified the relevant Competent Person Schemes providers and we will also be writing to local building control due to the number of concerns identified and the frequency of these issues with this installer.

Specflue visited this installation within 24hrs of being notified. On arrival we were surprised to find that the installing company had already started to remove the appliance prior to it being assessed in position. Despite this, the faults were still visible as the appliance still had the incorrect size ventilation, incorrect flue configuration and the position of the flue draft stabiliser was still able to be ascertained. This could be why the inspector in Burnardo’sview “did not inspect the appliance” as it had already been taken out and was not under fire or connected to any heating circuit or flue system, but rather was sat in the middle of the kitchen floor. Nevertheless all the run time and data from the appliance menu system had been recorded, indicating that the engineer did check the appliance in this instance, as this can only be obtained by querying the appliance menu system.

I think it is important to add that the appliance model has recently undergone independent inspection and testing by KIWA. The outcome of the report and tests have clearly indicated that the issues with this appliance are directly related to poor installation practice and the regime adopted to clean the appliance and the frequency, also repeatedly overriding failed ignition warnings. More guidance to the homeowners and improved documentation will be implemented by MCZ following the report. Also a new safety feature to compensate for possible poor installation and maintenance will be added to ensure the stove cannot suffer failure with the glass.

Specflue is happy to discuss these issues directly and would respectfully request that thorough due diligence is undertaken when considering why these incidents occur. MCZ is Europe’s largest domestic biomass provider and has sold thousands of products across many countries. The current investigation of explosive ignitions equates to less than 1/5th of a percent of those installed.

The incidents in the UK have common installation issues around ventilation and flue and noncompliance with MIS3004, approved Doc J and ventilation requirements and sizing. To try and explain this situation, it could be compared to a car (as previously mentioned in this thread) If you were to restrict the exhaust so it did not work properly and then restrict the air flow in to the engine, and then kept adding fuel and a spark for ignition, expecting it to be ok, what would happen to the engine eventually? It is paramount that homeowners fully understand the required standard these stoves and any biomass boiler should be fitted to and to be in aposition to challenge any poor installation practise. Independent help and advice on this can be provided by HETAS and also MCS.

Specflue has represented itself on this forum, not hiding behind any user name. It is unfortunate that on forums people can be anonymous or profess to be someone else and utilise that to influence others. If any homeowners have any complaints or would like more details please feel free to contact us and we will be happy to share what we know, as we know it, on behalf of MCZ.

We would also welcome any feedback in relation to the behaviour and thoroughness of any site visits conducted as soon as it is experienced. Only then will we have the opportunity to manage and improve our service, in particular around these difficult situations.

Specflue will continue to conduct thorough assessments of these installations and provide feedback to the industry and homeowners alike, in an effort to continually raise the standards in this newly emerging sector.