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Vitodens question

S Ebels
S Ebels Member Posts: 2,322
in THE MAIN WALL
Pester your installer for help B4 you get Viessmann involved. If he put it in he should have at least basic knowledge of the programming functions for the Comfortrol.

I didn't understand your reply regarding the day/night temp settings.

Comments

  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    Vitodens question

    Thanks to advice from this forum and several winters of severe discomfort I have junked my entire steam heating system and am installing a new system from scratch at great cost and massive inconvenience. I look forward to many years of comfortable heating and cooling once this is done and I thank everyone for their input to my sporadic postings.

    A Vitodens 200 6-24 has just been installed in my basement with a Vitocell 300 hw indirect. The contractor has a sterling reputation here and elsewhere, but this is their first Viessmann installation. I was not worried about the lack of Viessmann experience because Viessmann has such a strong reputation for standing behind their equipment.

    The boiler has 3 circulating zones, for hw, for heating the 1st floor panel radiators with TRV's, and a dormant zone for a future hydro-air system on the 2nd and 3rd floors. Each radiator has its own pex supply and return.

    The system worked fine for about a week. Another plumber caused problems by first slightly opening the bypass valve to the pressure reducing valve, flooding the boiler, and then by welding through the electrical cable that powers the boiler. As far as I know, the system then worked fine for three days and then exhibited these problems:

    It would shut down completely around 10pm each night and go back on in the morning.
    It would no longer heat the room to 73-74 degrees, as before, but would only get to 68-71 degrees ambient temperature. And this was after increasing the setting on the TRV higher than it had been previously.

    Night reset seems the obvious culprit. Originally, the night reset was set to no change and the same target temperature as daytime. Upon consultation with the rep, the tech changed the night reset time (to 0:00 and 24:00, I think) so that night reset is supposed to be bypassed completely. That was yesterday.

    The rep also had the tech change my shift on the curve from 10C to 0C. I don't see how the shift can affect when the boiler goes on or off, but it was set back to 0C yesterday and today I turned it up to 3C.

    Boiler still went off last night around the same time.

    Does anyone have any idea what can be causing this behvior? The installer wants the rep to look over the boiler, but they have been very slow to come, which surprises me given Viessmann's reputation, and we will have family sleeping over for the holidays.

    Thank in advance.
  • John Jr
    John Jr Member Posts: 210
    Viessmann

    Frank, give James Brown a call from Viessmann 401-732-0667 explain the problem to him and follow his directions. It sounds very much like a programing problem. From taking a shock like you mention you might have to start from scracth on the programing by reseting it.
  • S Ebels
    S Ebels Member Posts: 2,322
    Where are

    Where are the day and night (sun and moon dials set on the front of the boiler programmer?
  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    Where are

    at 12 o'clock.
  • joel_19
    joel_19 Member Posts: 933
    program

    Go through the program and take a look it's pretty easy as it's all on the screen . Your installer should do this for you . He should go through the manual . With all do respect i don't see how it's the reps problem this should be done by the contractor.
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928


    If the boiler goes "off" again, look at the display. If you see a little crescent moon, the boiler is in reduced temp mode. Since you say that the reduced temp mode timer is set for "no time" you should see a little sun. If you set the moon and sun dials to the same temperature, reduced temp mode is effectively cancelled regardless of the timer settings.

  • ALH_4
    ALH_4 Member Posts: 1,790
    Coding

    Verify all of the coding. Follow the "Quick Startup Guide" if you have it. In particular the 000 and 0B8 codes should be verified. Your installer should know all of this after having set the coding originally. If a non-combi boiler is set to combi, it does strange things. Who knows what might have happened when the wire was melted.

    -Andrew

    P.S...Brown-outs and other power supply problems (similar to what might have happened when the wire was melted) can cause the Vitodens to "lose" its settings.
  • John Felciano
    John Felciano Member Posts: 411
    Sounds

    Like a control program error.Check the timer function 0:00-24:00 should be for "ALL days",it's a seven day function so the setback needs to be set accordingly.

  • heatboy
    heatboy Member Posts: 1,468
    The control...

    defaults to night setback at 10 PM

    There was an error rendering this rich post.

  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    Status report

    Installer came Wednesday before Thanksgiving. He studied this thread ("These people really know their stuff.") and was on the phone with the rep for quite some time down at the boiler.

    He said that if the 10pm shutdown happened again to let him know and he would come in the morning to bipass the controls either with a thermostat (in the unheated basement) or just jumping the wires.

    The boiler shut down around 10pm. The compute displayed a sun symbol, so I guess that means it was not on night reset.

    I left a message. At 2am my son, who was playing computer games with his sister back from college, woke us up to ask if we were expecting the heating person. By the time I got down to the basement, the installer had already left and told my kid that he had fixed the problem.

    Surely the installer deserves an award for coming at 2 in the morning of a major holiday.

    I suspect he has not found a permanent fix, but I'll post what I know after the holiday, which I hope everyone enjoys with familiy and loved ones.
  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    The envelope please...

    Turns out the installer solved the going off at 10pm problem when he came at 2am on Thanksgiving.

    The problem was not with the night setback, but something that sounded like "domestic recycler." Apparently there is a separate setting for the timing of each circulating pump. This was turning the circulator off each night and on each morning.

    The other question, why I can't get room temperature above 70 or 71 degrees, in the absense of any inside thermostat and with panel radiators deliberately oversized, remains. the family wants 74 degrees.

    I have set the shift for plus 6 centrigrade and changed the normal room temperature nob from 68 to 75 yesterday. This has only gotten me to 71.1. Today I have turned the TRV's to maximum. Turning up the TRV's is illogical, because two weeks ago they gave me a temp of 74 at a much lower setting, but I want to make sure I can eliminate them as a variable.
  • ALH_4
    ALH_4 Member Posts: 1,790
    DHW Circulation

    The expansion board installed in the power module can be used to power a domestic hot water circulation pump or the heating system circulator depending on the coding. There are a lot of possibilities for reasons why you cannot heat the rooms to 74. There is a 167F high limit on the boiler. Also is the circulator properly sized? I assume the low loss header was used. What circulator is on the system side? If it's a 3-speed is it on speed three? Where is the differential pressure bypass valve set? What is the slope of the heating curve? How hot is the boiler when the rooms are 71F? Do you have digital photos of the mechanical room?

    -Andrew

  • S Ebels
    S Ebels Member Posts: 2,322
    Not heating sufficiently?

    You need to look at the boiler temperature when you get into the "not hot enough" condition. If the boiler is at 160*+ it's doing all it is designed to do. period. If this is the case your rads were not sized to provide the needed heat output at that water temp. Or you have a circulation problem.

    If the boiler is running 120-140 or so, you have some room to move your shift and or slope up a notch or two. Do it gradually, one point at a time until you can leave the TRV's at a normal setting, about 3, and still have sufficient heat.

    You could also check to see what the actual water temp is, going out to the rads with a thermometer. This would tell you if you have some unwanted "blending" of return and supply water which would need to be remedied.

    What exactly is your shift and slope set at right now? What was the outdoor temp when the heat was OK and what was it when the house was cool?
  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    DHW Circulation

    Digital photos attached.
    Labels on photo 648 A-to radiators, B-for future hydro-air, C-to Vitocell 300 in next room, E-temporary fresh air source, F-temporary condensate container.

    The switch on the circulator pump is to the left of the three positions, which I believe is the highest setting.

    Boiler water temperature - 151F. At that water temperature, assuming it got to the radiators, the radiators should be outputting somewhat more BTU's than the heat loss for the space at design temperature (8F). Since I set the TRV's for maxiumu temperature, several hours ago, the indoor temperature has gone up from 71.1 to 72.0. The system should be perkier than that.
  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    Not heating sufficiently?

    Slope 1.6
    Shift 6
    Max 180

    As I said in a previous post, at 151 boiler water temp, unless the installer and I miscalculated horribly, the boiler is putting out enough BTU's.

    There may be a problem with the layout of the radiators. We only have 4 radiators at the moment, and they are in pairs. Each radiator in the pair has its own TRV's. The radiators are less than a foot apart. If both TRV's in the pair are set at the same setting, one radiator does not get hot. I just turned down a pair of the largest standard size Myson Eclipse's to 4, and one stayed real hot and the other one went cold. Even by the boiler, the supply pex line went cold.

    The way the rads are set up, the TRV's are on the right and the furthest radiator from the boiler is on the right (see photo). It is the boiler on the right that stops working. The TRV on the rad that is not working is pretty far 7-8 feet from the one that is hot, so I don't see why it would turn off while the TRV on the first radiator, which is less than a foot from the second radiator works fine.

    I had forgotten about this issue because I had learned to turn the second TRV a quarter or a half notch higher than the first, but this clearly is not normal.
  • ALH_4
    ALH_4 Member Posts: 1,790
    Piping

    Those pex lines look like 1/2" nominal diameter tubing. How much radiator is connected to one of those branches? What is the heat load for the radiator zones total? The Vitodens is limited to 167F at the highest. Also, not to nit pick, but the Viessmann fittings are for 87 degrees. The seal on the exhaust pipe might be compromised at that angle.

    -Andrew
  • [Deleted User]
    [Deleted User] Posts: 1,160
    Sounds like...

    the radiators are in series. Supposed to be in parallel.

    ME
  • mph
    mph Member Posts: 77
    Other things to look at

    Two more things to consider:

    The max rotation on the heating circuit pump is set to 65% on high fire and 45% on low-fire (coding address 045 and 046). You may be getting too large a dt at that low speed.

    The max boiler temp can be also be raised to 180 F (coding address 042). This should only come into play if the boiler temp is maxing out at 167 now.

    In either case, it looks like your boiler won't be operating in condensing mode for much of the year.

    Jeff
  • Joel_3
    Joel_3 Member Posts: 166
    ?

    Why is there no lowloss header and what kind of flue pipe is that? and where does it go ? it does not look like the Viessmann vent pipe and that angle does not look correct .

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  • [Deleted User]
    [Deleted User] Posts: 82
    definitely not according to the installation manual

    Check your installation instructions, call your rep, consult with a professional, PLEASE
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928


    Must agree--DEFINITELY not according to the instruction manual.

    You don't necessarily need a low-loss header if you have TRVs/FHVs on EVERY emitter, but in that case there won't be other circulating pumps lurking around...

    The slope of the horizontal part of the vent looks so extreme that you can't install the outside of the venting slip coupling. I know the venting is expensive but you need some more vertical vent pipe!

    That sure doesn't look like a Viessmann terminal either.

    If this was professionally installed I think you might have legitimate grounds for a lawsuit!

    A true pity to see such a fine boiler so ignorantly installed!
  • Paul Pollets
    Paul Pollets Member Posts: 3,666
    I'd agree...

    parallel piping only for WPRads...the boiler installation looks "compromised", to say the least. Sealed combustion is the purpose. Leaving out the last piece will result in dirst and dust entering the combustion chamber. Shoving the vent into a 6" or 8" sleeve....How does the vent terminate? I'd be contacting the local Viessmann rep for a checkup to make sure it's going to work properly.

    BTW, Viessmann requires the LLH if flow rates exceed 7gpm. Did the contractor do the math??

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  • Mark Hunt
    Mark Hunt Member Posts: 4,908
    Paul


    Please post a picture of one of your installs for this gentleman.

    So he can see what they are supposed to look like.

    Mark H

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  • Mark Hunt
    Mark Hunt Member Posts: 4,908
    Paul


    Please post a picture of one of your installs for this gentleman.

    So he can see what they are supposed to look like with ALL of the components.

    Mark H

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  • Joel_3
    Joel_3 Member Posts: 166
    instal

    That would never pass code in Mass . Makes you wonder why the manufacters don't demand that people get certifies by them to do an instal......

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  • Paul Pollets
    Paul Pollets Member Posts: 3,666
    Vitodens....

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  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928


    My own Vitodens install isn't pretty by "The Wall" standards but it follows the instructions to the letter. Of course it's damned easy to connect a Vitodens to a TRVd system with zero head loss in the piping...

    Now I just have to figure out how to make "super simple" radiant designed for a cast iron boiler and plenty of available pump head work when the Vitodens heating curve is optimized for fuel efficiency.
  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    What I know

    I will answer questions as best I can:

    Largest radiator served by 1/2" pex -- 19,795 at 81F temp differential, 28,278 at 108F differential.

    The radiators are installed in parallel, not series. They come off a manifold and each has a TRV (as can be seen in the photos.) One possibility the installer has come up is that the TRV's, if they are manufactured as other, lesser TRV's are made, may be imprecise. That is going to be easy to check by switching the TRV's between boilers on each pair. If different radiators are cold when the TRV's are at the same setting, then that is the problem. If not, we'll need new ideas.

    The radiator sizing is no doubt impacted by the fact that the radiators for the basement have not yet been installed (basement is not too cold, tho, and the floor has a good R value) and by the fact that the hydro-air for the 2nd and 3rd floor is not in yet (tho there are electric radiators plugged in there.) So they may be compensating for the parts of the system that are not installed yet --but there has only been one day below freezing here in NYC. The basement radiators should go in the end of next week, the hydro air in 3 to 4 weeks. The boiler is not on very much, even in colder days, and the return water is much cooler than the supply, so maybe the radiators are mismatched to their (hopefully) temporary loads.

    The Viessmann rep has supposed to be coming to look at the venting for about 5 weeks now. Obviously, I am not party to the conversations betweent the rep and the installer. Sometimes, I know, people outside the city hate to come to Manhattan, but, as I said, I do not know the story. I am a little surprised it has taken this long for a luxury product to be seen to, whatever the reason. The installer knows he needs help on the venting and says he is waiting on the rep (again, I am just a second-hand source.) Since this is a row house, I have had to vent through the chimney. The horizontal vent pipe in the photo enters a chimney chase and goes up 45-50' to the roof. Installing through a chimney is allowed in the Technical Data Manual, as a third method. The PVC you see is a sleeve for the metal vent pipe. The unit is in a 700SF basement and is next to a source of outside air, so fresh air, whether indoor or outside should not be a problem once the installer is instructed how to proceed. I can't say anything about the angle, but know that in photographs angles are subject to distortion, so I'll check that with the rep and the installer. In fact, I'm not even sure I know which angle should be 87 degrees.

    As far as the LLH, all I know is that there are 3 zones, if you will. One is the Vitocell 300. One, which is not set up yet, will be for a hydro-air system, and the third consists of radiators, each with its own TRV. The circulator for the radiators will be on constantly during the heating season. The hydro-air will have a thermostat, I believe, to make sure it receives adequate hot water and only when needed. This will affect the reset curve and compromise the efficiency of the boiler, but I am putting central air in two floors and this seemed like a way to simplify the installation bother, save installation cost and increase usable wall space by eliminating radiators.

    I would love to refer to installation instructions, but Viessmann only posts the Technical Data Manual on the Web site, so the other manuals are unavailable to me. I understand if they don't want technical information misused by mere owners. But the same embrace of technology and learning that led me to the Viessmann makes me want to have access to all technical information. If it is profitable to people to have access to the same medical research as physicians, sometimes with life-saving results, boiler companies should realize that users want access to technical information and should be trusted with it. I do feel a little frustrated to see a fault code and not even know what it represents. I am not interested in installing or repairing my own boiler, and I can't imagine anyone who can afford a Viessmann (and is not a pro) wanting to do so. But I do know that no one cares as much about my house as I do, and that is why web sites like The Wall are not only valuable, but indispensable, and having access to the same information as the installer is part of the same package.

    The person who installed the boiler plans to go to Viessmann school at the earliest opportunity. I must take responsibility for knowingly hiring an installer who had never installed a Viessmann before, but I have had good experience with the company doing the job, and the have an excellent reputation (at least according to Dan Holohan.) So I was relying on the sterling reputation of both the installer and Viessmann to see the project through. The installer presumably took into account that it would have glitches that are a normal part of the learning curve, but that hit would be more than repaid in applying its knowledge to future Viessmann jobs they hope to get.

    I must say on the positive side that I am getting literally gallons of condensation, even on warm days. And I love the sound of the boiler when it fires. After having had tons of conventional infernos, the Viessmann flame sounds so precise and measured, like it knows where it is going and what it is doing.
  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    What the rep said

    Thanks everyone for your suggestions.

    The distributor sent two techs, one very senior who normally does not look at residential installs, last Thursday. They did an excellent job, answering all questions and explaining things clearly even for me, the ignorant homeowner.

    There is no need for a LLH. There are 3 notional zones. The internal pump in the boiler handles 1 --the Vitocell 300 indirect. Zone 2 is a hydro-air system that will be installed in a week or so for the 2nd and 3rd floors. This zone will control the boiler temperature, in effect. Zone 3 consists of 6 myson panel radiators for the 1st floor and basement. Each radiator has its own TRV. Viessmann might like LLH's, according to the rep, but one is not needed in my setup.

    The venting, however, explains Viessmann's lack of support. The installer vented through the chimney, which is ok. But he completely disregarded two of Viessmann's requirements. Installer wanted fresh air to come through the chimney chase. Viessmann said absolutely not. And it did not work. Installer also ran flexible ducting through the chimney. Viessman will not allow that. So, until the venting is brought into compliance with the manufacturer's specs, manufacturer will not even answere questions about the system. First installer will use the recommended ductwork for the chimney as spec'd by the rep and proceed from there.
    Once the boiler is brought into compliance, suppport and warranty service from manufacturer will be restored.

    One change I will have to make is to seal off the boiler from air circulation with the rest of the house. It's in a kind of niche now, so I just have to build a sheetrock wall and tightish door to close it in.

    It was really nice of Paul to post a picture of one of his installations. It's a neat job, but, except for the two admittedly unfinished areas of venting and condensate drain, I do not see how it differs from my job? (The installer was concerned that Paul's gas line might be undersized, but that depends on the specific model and whether he's using propane, apparently.) If there are other points to learn from it, I would be glad for the knowledge.

    One of the radiators was not working, it turns out, because the TRV was not seated properly.

    There are still problems, I believe, with the settings. This is reflected in the fact that I cannot get the boiler temperature above 158°, even though the max is set at 180° and, once or twice the radiators have been cool in the morning, although that problem is not as it once was.
  • Frank Dobbs
    Frank Dobbs Member Posts: 27
    What the rep said

    Thanks everyone for your suggestions.

    The distributor sent two techs, one very senior who normally does not look at residential installs, last Thursday. They did an excellent job, answering all questions and explaining things clearly even for me, the ignorant homeowner.

    There is no need for a LLH. There are 3 notional zones. The internal pump in the boiler handles 1 --the Vitocell 300 indirect. Zone 2 is a hydro-air system that will be installed in a week or so for the 2nd and 3rd floors. This zone will control the boiler temperature, in effect. Zone 3 consists of 6 myson panel radiators for the 1st floor and basement. Each radiator has its own TRV. Viessmann might like LLH's, according to the rep, but one is not needed in my setup.

    The venting, however, explains Viessmann's lack of support. The installer vented through the chimney, which is ok. But he completely disregarded two of Viessmann's requirements. Installer wanted fresh air to come through the chimney chase. Viessmann said absolutely not. And it did not work. Installer also ran flexible ducting through the chimney. Viessman will not allow that. So, until the venting is brought into compliance with the manufacturer's specs, manufacturer will not even answere questions about the system. First installer will use the recommended ductwork for the chimney as spec'd by the rep and proceed from there. Once the boiler is brought into compliance, suppport and warranty service from manufacturer will be restored.

    One change I will have to make is to seal off the boiler from air circulation with the rest of the house. It's in a kind of niche now, so I just have to build a sheetrock wall and tightish door to close it in.

    It was really nice of Paul to post a picture of one of his installations. It's a neat job, but, except for the two admittedly unfinished areas of venting and condensate drain, I do not see how it differs from my job? (The installer was concerned that Paul's gas line might be undersized, but that depends on the specific model and whether he's using propane, apparently.) If there are other points to learn from it, I would be glad for the knowledge.

    One of the radiators was not working, it turns out, because the TRV was not seated properly.

    There are still problems, I believe, with the settings. This is reflected in the fact that I cannot get the boiler temperature above 158°, even though the max is set at 180° and, once or twice the radiators have been cool in the morning, although that problem is not as it once was.
  • ALH_4
    ALH_4 Member Posts: 1,790
    LLH

    Whether or not you need a LLH is based on the flow rate required to deliver enough heat to your home from the boiler. If the required flow rate is much over 4gpm (approx 40,000 btu @ 20F dT and based on standard piping practices), you likely need a LLH and secondary pump. In general the indirect hot water heater does not count as a zone, as it is prioritized over the heating circuits. Viessmann always recommends a Low Loss Header (with the exception of the 6-24 Combi). I believe this is because of the tendency of installers to treat them as they would a traditional low-head-loss boiler. There are instances where the Low Loss Header is not necessarily needed. It takes some design in order to be sure whether or not it is needed.

    You will never get a Vitodens to 180F. They cannot go beyond 167F. It sounds as if the settings and coding are still questionable. It takes some time to become comfortable with the way the Vitodens works. The information is in the manuals, but it is not always easily found.

    -Andrew
  • David Van Wickler_3
    David Van Wickler_3 Member Posts: 63
    There are a few issues here

    and can be addressed systematically as soon as the venting is corrected. We will be back at the site as soon as the venting is corrected and at that time we'll look at the piping of the radiators and other issues, regardless of who did what when or why. The end result is the customers satisfaction.

    It would also be helpful to visit the heat loss and the literature for the panel radiators (i.e. the output of the radiators versus water supply temperature).

    The boiler codes can all be adjusted. There have been two occasions that I simply reset the codes back to factory settings since there were so many "fingers" pressing the buttons.

    Also - all of the radiators need to be installed and plumbed.

    Wales Darby Inc. stands behind their products.
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