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Viessmann rubber hose problems

dr911
dr911 Member Posts: 20
edited December 2021 in Gas Heating
Are the rubber hoses (flow and return hoses connected to the heat exchanger) known to fail on the 2016-2019 Viessmann Vitodens 100W?

I've been dealing with circulation issues inside the boiler and I've found some anecdotal reports online of "crunchy hose syndrome" aka black granules or flakes.





Images from various youtube videos showing this issue

Viessmann auth service wants to replace the entire heat exchanger on a 5 year old boiler.... Shady. I don't have rads, only underfloor heating. The rubber hose in the back is annoying to replace as the whole heat exchange has to be removed on the 100W. I found out about this on my own as three heating service companies already have looked at the boiler and didn't even mention this as a possibility despite having found flakes in the heating water and in the plate heat exchanger.

Any suggestion of the best method to get rid of these?

- drain entire heating system and boiler
- change hoses
- flush boiler and UFH loops with clean water
- maybe install a filter on the return to catch other remaining flakes
- add inhibitor ?

Comments

  • Derheatmeister
    Derheatmeister Member Posts: 1,524
    From the pictures you posted it looks like you may have some sort of Rubberhose for your heat distribution.
    It most likely does not have a O2 barrier which Viessmann rightfully will Void any warranty on this boiler..
    We have seen issues when these kinds of materials used in hydronic heating systems....
    It does not matter which Brand is hooked up to it..
    IMO Rubberhoses should not be used in Heating systems
    IMO this is Not Viessmanns issue
    Alan (California Radiant) Forbes
  • Derheatmeister
    Derheatmeister Member Posts: 1,524
    edited December 2021

    From the pictures you posted it looks like you may have some sort of Rubberhose for your heat distribution.
    It most likely does not have a O2 barrier which Viessmann rightfully will Void any warranty on this boiler..
    We have seen issues when these kinds of materials used in hydronic heating systems....
    It does not matter which Brand is hooked up to it..
    IMO Rubberhoses should not be used in Heating systems
    IMO this is Not Viessmanns issue

    1. You should repipe the system using an O2 barrier type Pex
    2. Change the HX on the Viessmann
    3. Protect your investment by using a inhibitor/Glycol or use deionized water as per VDI 2035..
  • GW
    GW Member Posts: 4,691
    No way that’s the boiler causing that- that yuk is from something else 
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
    DerheatmeisterAlan (California Radiant) Forbes
  • Derheatmeister
    Derheatmeister Member Posts: 1,524
    GW said:

    No way that’s the boiler causing that- that yuk is from something else 

    Gary. IMO he should have called this thread "Rubber hose Problems" Vs. Viessmann rubber hose problems.. :s
    GW
  • dr911
    dr911 Member Posts: 20
    edited December 2021
    Those hoses are the flow and return hoses inside the Viessmann 100. They are connected from the hydraulics to the hear exchanger. That’s how Viessmann manufactured the 100-W. These aren’t hoses in my heating system. I just have pex UFH pipes and a manifold, no rads. 
  • Derheatmeister
    Derheatmeister Member Posts: 1,524
    dr911 said:

    Those hoses are the flow and return hoses inside the Viessmann 100. They are connected from the hydraulics to the hear exchanger. That’s how Viessmann manufactured the 100-W. These aren’t hoses in my heating system. I just have pex UFH pipes and a manifold, no rads. 

    I have never seen any rubber hoses inside any 100 series boilers..
    Can you post some pictures of the rubber hose that is installed INSIDE of the Viessmann boiler cabinet...BTW are you in GB ?
  • dr911
    dr911 Member Posts: 20
    edited December 2021
    This is how the inside of a 100-W is. This isn't my boiler, I have a combi version but the hoses are the same.


    The long flow tube starting at the top of the HE. 2017 100-W. I'm in Europe.
  • GW
    GW Member Posts: 4,691
    So, the Germans make poo for their own population and send the Americans the better-built boilers—-got it 😀
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
    Alan (California Radiant) ForbesSolid_Fuel_Man
  • kcopp
    kcopp Member Posts: 4,418
    Makes me wonder if it an open vented system. They do still have those over there.
    Derheatmeister
  • Derheatmeister
    Derheatmeister Member Posts: 1,524
    dr911 said:

    This is how the inside of a 100-W is. This isn't my boiler, I have a combi version but the hoses are the same.


    The long flow tube starting at the top of the HE. 2017 100-W. I'm in Europe.

    As you said...Rubber hoses,
    The US version of this boiler has Copper.
    I have never seen any Viessmann boilers from the WB2A..WB2B..HA.. all the way up to the CU series boilers that have Rubber hose..
    I personally like hard pipe.
    Looking at the pictures it seems that you may have some larger problem with O2 ingest and ferrous materials.
    As kcopp said some of the european systems have a open expansion tank
    In my trade years in Germany i have seen some of these open tanks that where located in the attic and vented on the roof.
    Is the redish debrie magnetic/ferrous material/Magnetite?..Take a magnet to it !
    I would sample the fluid and check it for PH..EC..TDS..SAL..CU..Iron..Hardness.
    What brand is your infloor tubing, and does it have a O2 barrier ?
    Can you post more pictures of your heat distribution/manifolds/Tubing and the mechanical room ?

  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 3,976
    edited December 2021
    @Derheatmeister:
    I didn’t think Europe ever used non-barrier tubing. 
    I remember on one of my jobs I tried to re- use the existing expansion tank in the attic that was vented through the roof, but soon realized that the roof wasn’t high enough to allow enough pressure to satisfy the boiler’s pressure switch. 
    Curious about where all that debris is coming from. Can you take a picture of your manifold so we can see the tubing?
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • Derheatmeister
    Derheatmeister Member Posts: 1,524

    @Derheatmeister:
    I didn’t think Europe ever used non-barrier tubing. 

    I remember on one of my jobs I tried to re- use the existing expansion tank in the attic that was vented through the roof, but soon realized that the roof wasn’t high enough to allow enough pressure to satisfy the boiler’s pressure switch. 
    Curious about where all that debris is coming from. Can you take a picture of your manifold so we can see the tubing?
    Alan,
    Before the VDI 4726 which only allows 0.1mg of O2/Liter/Day the Europeans also had their share of issues associated with none O2 barrier tube..
    Some companies are now specializing in restorations of this type of tubing/Adding a O2 barrier after the fact.

    To the Roof expansion tank: 2.31 feet of water in a colum will give you 1 PSI...
    If your Open expansion tank was approx. 23 feet higher than a 10 PSI LWCO Switch it would be on the edge..
    IMO Open Expansion tanks need to be eliminated since they allow a constant oxygen ingest.

    I agree..Looking at some of the cut up tubing it seems that the system has large amounts of Iron debrie (the magnet in the lower left side of the picture has ferrous material on it).
    Viessmanns 100 series boilers are made of Stainless Steel (316 TI)
    Where is this Iron debrie coming from if the dr911 states the he only has UFH "Under Floor Heat" ?
    Something else is going on here !
    kcoppAlan (California Radiant) Forbes
  • dr911
    dr911 Member Posts: 20
    edited December 2021
    Flow: copper
    Return: copper
    Manifold: brass
    Underflood heating: PERT-AL-PERT (Raised Temperature Polyethylene) tubes with oxygen barrier.

    Flakes seem to be coming from the tubes themselves, possibly porous? Not magnetic.
    Multiple people having similar issues on various UK/EU forums.
    Viessmann does not acknowledge problem.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Viessmann knows that any rubber hose in a boiler wouldnt fly here in North America. We already went down the EPDM rubber tubing path in the 1990s. It didnt end well.  
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Derheatmeister
    Derheatmeister Member Posts: 1,524
    dr911 said:

    Flow: copper
    Return: copper
    Manifold: brass
    Underflood heating: PERT-AL-PERT (Raised Temperature Polyethylene) tubes with oxygen barrier.

    Flakes seem to be coming from the tubes themselves, possibly porous? Not magnetic.
    Multiple people having similar issues on various UK/EU forums.
    Viessmann does not acknowledge problem.

    The Picture that you posted are from an other system >>NOT YOURS<<
    The Youtube Video does not reveal everything This system may have had iron componets and other issues......
    Can you please post pictures of you own situation.
    How much none magnetic flakes are coming out of Your system.
    I sugest a full system flush followed by installing a system cleaner such as Fernox F3
    which is to be flushed after it made full contact with all the tubing
    Then you can deside if you want to go the Chemical or None Chemical route in conjuction with a Filter such as the Fernox TF1 or a sacrificial anode setup..
    IMO You need to first check your system fluid as mentioned above PH,EC,TDS.SAL,CU,FE,Hardness...
    Again...Even with the Rubber tube in the boiler ,I Do not think this is a Viessmann Issue !
  • dr911
    dr911 Member Posts: 20

    dr911 said:

    Flow: copper
    Return: copper
    Manifold: brass
    Underflood heating: PERT-AL-PERT (Raised Temperature Polyethylene) tubes with oxygen barrier.

    Flakes seem to be coming from the tubes themselves, possibly porous? Not magnetic.
    Multiple people having similar issues on various UK/EU forums.
    Viessmann does not acknowledge problem.

    The Picture that you posted are from an other system >>NOT YOURS<<
    The Youtube Video does not reveal everything This system may have had iron componets and other issues......
    Can you please post pictures of you own situation.
    How much none magnetic flakes are coming out of Your system.
    I sugest a full system flush followed by installing a system cleaner such as Fernox F3
    which is to be flushed after it made full contact with all the tubing
    Then you can deside if you want to go the Chemical or None Chemical route in conjuction with a Filter such as the Fernox TF1 or a sacrificial anode setup..
    IMO You need to first check your system fluid as mentioned above PH,EC,TDS.SAL,CU,FE,Hardness...
    Again...Even with the Rubber tube in the boiler ,I Do not think this is a Viessmann Issue !</p>

    Yes I wrote in my original post those are photos from youtube vids similar to my situation. I couldn't take a photo or video when the service guys were there.

    Did system flush with ADEY MC3+ (similar to F3) for 1 month then flushed.
    Did power flushing for 2h with chemical/acid from flow/return of main heat exchanger by Viessmann tech.
    Filter of course will be installed now that I have seen what was inside.
    Thing about inhibitors is that apparently Viessmann doesn't recommend inhibitors in the heating water. OK but then why do they blame the water? Am I supposed to go out and buy 120L/30gal. of deminteralized water and a pump to get it in in the floor heating? I'm no boiler tech/plumber just a customer..
  • Derheatmeister
    Derheatmeister Member Posts: 1,524
    dr911 said:

    dr911 said:

    Flow: copper
    Return: copper
    Manifold: brass
    Underflood heating: PERT-AL-PERT (Raised Temperature Polyethylene) tubes with oxygen barrier.

    Flakes seem to be coming from the tubes themselves, possibly porous? Not magnetic.
    Multiple people having similar issues on various UK/EU forums.
    Viessmann does not acknowledge problem.

    The Picture that you posted are from an other system >>NOT YOURS<<
    The Youtube Video does not reveal everything This system may have had iron componets and other issues......
    Can you please post pictures of you own situation.
    How much none magnetic flakes are coming out of Your system.
    I sugest a full system flush followed by installing a system cleaner such as Fernox F3
    which is to be flushed after it made full contact with all the tubing
    Then you can deside if you want to go the Chemical or None Chemical route in conjuction with a Filter such as the Fernox TF1 or a sacrificial anode setup..
    IMO You need to first check your system fluid as mentioned above PH,EC,TDS.SAL,CU,FE,Hardness...
    Again...Even with the Rubber tube in the boiler ,I Do not think this is a Viessmann Issue !</p>

    Yes I wrote in my original post those are photos from youtube vids similar to my situation. I couldn't take a photo or video when the service guys were there.

    Did system flush with ADEY MC3+ (similar to F3) for 1 month then flushed.
    Did power flushing for 2h with chemical/acid from flow/return of main heat exchanger by Viessmann tech.
    Filter of course will be installed now that I have seen what was inside.
    Thing about inhibitors is that apparently Viessmann doesn't recommend inhibitors in the heating water. OK but then why do they blame the water? Am I supposed to go out and buy 120L/30gal. of deminteralized water and a pump to get it in in the floor heating? I'm no boiler tech/plumber just a customer..
    dr911 said:

    dr911 said:

    Flow: copper
    Return: copper
    Manifold: brass
    Underflood heating: PERT-AL-PERT (Raised Temperature Polyethylene) tubes with oxygen barrier.

    Flakes seem to be coming from the tubes themselves, possibly porous? Not magnetic.
    Multiple people having similar issues on various UK/EU forums.
    Viessmann does not acknowledge problem.

    The Picture that you posted are from an other system >>NOT YOURS<<
    The Youtube Video does not reveal everything This system may have had iron componets and other issues......
    Can you please post pictures of you own situation.
    How much none magnetic flakes are coming out of Your system.
    I sugest a full system flush followed by installing a system cleaner such as Fernox F3
    which is to be flushed after it made full contact with all the tubing
    Then you can deside if you want to go the Chemical or None Chemical route in conjuction with a Filter such as the Fernox TF1 or a sacrificial anode setup..
    IMO You need to first check your system fluid as mentioned above PH,EC,TDS.SAL,CU,FE,Hardness...
    Again...Even with the Rubber tube in the boiler ,I Do not think this is a Viessmann Issue !</p>

    Yes I wrote in my original post those are photos from youtube vids similar to my situation. I couldn't take a photo or video when the service guys were there.

    Did system flush with ADEY MC3+ (similar to F3) for 1 month then flushed.
    Did power flushing for 2h with chemical/acid from flow/return of main heat exchanger by Viessmann tech.
    Filter of course will be installed now that I have seen what was inside.
    Thing about inhibitors is that apparently Viessmann doesn't recommend inhibitors in the heating water. OK but then why do they blame the water? Am I supposed to go out and buy 120L/30gal. of deminteralized water and a pump to get it in in the floor heating? I'm no boiler tech/plumber just a customer..

    Leaving the cleaner in the system for 1 month seems a little excessive and i do not know if it could cause a Issue..
    At 8.33 LBS per Gallon that could be a lot of Schlepping>>250LBS<< :s one would also have to recycle of a bunch of plastic containers, o:)
    I recommed using a Mixed resin bed filter such as the Puropal 300 from Elysator or VEP 300 from Magnetic to fill your system via a Hose.
    Check out the Caleffi Idronics #18 for more information.
    Are you in Great Britain ? If so i could Link you to a distributer that can probably help.
    Richard.
  • kcopp
    kcopp Member Posts: 4,418
    Typically Fernox/ Adey is only supposed to be left in for 1 week/ 10 days.. After that the cleaner loses it effectiveness... the ability to bring the junk back into suspension weakens.
    Derheatmeister
  • Derheatmeister
    Derheatmeister Member Posts: 1,524
    Okay... I am going to go out on the limb ..
    If you are in England one of the companies you could talk to is Zerochem
    Again For England https://www.zerochem.co.uk/
    If you are in Germany i would contact https://www.magnetic-online.de/
    If you were in the USA i would check out https://www.innovativehydronics.net/
    dr911
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Rubber (EPDM) hose is for cars....not heating. Worse than non barrier PEX. 
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • MassiveG
    MassiveG Member Posts: 1
    edited February 1
    Same problem this week. So it appears Wiessman don’t use inhibitor in Germany and tell you not to in the manual. But in the UK you have to if you don’t want to void insurance or have oxidisation in your heating system. Big problem because the inhibitor seems to disintegrate the rubber hoses in the Vitodens 100. I had one tiny bit of crud keeping the pressure release valve open, and more affecting the pumps in both Vitodens. Removed and worked fine. But don’t know the solution because the system needs inhibitor again. Unhelpful to say in US copper is used - even in other UK Vitodens models before and after copper is used, but we can hardly retrofit that now. Wiessman need to acknowledge this issue and supply hoses that don’t disintegrate.