+ Reply to Thread
Page 1 of 2 12 LastLast
Results 1 to 10 of 11
  1. #1
    Join Date
    May 2008
    Location
    New England
    Posts
    113

    Default regulating heat w/Buderus gas boiler

    We're @ our wits end with our Buderus natural gas boiler and logomatic computer - hoping someone here can explain why this 4 year old boiler can't seem to keep a 20' x 24' family room (on a separate zone) at 68 degrees. We have a Cape with 3 separate heating zones - the main house, the basement rec room, and the family room. The heating in main house and rec room zones "stay" wherever the thermostat is set. Can hear them click off and on when temperature drops or reaches the desired temps (main house is set @ 65, and rec room is set @ 60).

    The family room thermostat is set @ 68 because this room can easily drop to 66, 65, even 63 in the course of a day. At 6 a.m. today, the family room was a very comfy 68, however by the time we left for work the room was down to 65. We've just returned home from work and the room is down to 63. Why isn't it @ 68??????

    There is heat coming from the 4 baseboards in family room - baseboards are located on 4 walls of the family room - not nearly as hot as they were this a.m. when room was 68. Its beyond us how this space drops 5 degrees when the thermostat is set @ 68. And at other times is 68.

    We've had the HVAC folks out here a number of times - they've suggested not touching the thermostats (which we don't). They've also said its normal for a room's temp to drop 2 degrees (which would mean 66 is the norm when thermostat is set @ 68?). The family room is on a concrete slab. but the addition is well insulated.

    I maintain that if the other thermostats/zone can "heat" the other spaces to whatever the temp is set to, so should the family room.

    Any ideas or suggestions. I'm thinking we're wasting a lot of gas when the system "runs" non stop trying to reach 68, but can't get past 63, or 65 or 66. We've taken to heating this space with an electric space heater in the evenings cuz the space is "cold". It seems to "hit" 68 at times no one is in the space.

  2. #2
    Join Date
    Feb 2010
    Location
    South*East
    Posts
    1,183

    Default Re: regulating heat w/Buderus gas boiler

    Sound like there isn't enough baseboard in the room to overcome the heat loss.

    John

  3. #3
    Join Date
    Sep 2012
    Location
    Boston
    Posts
    888

    Default Re: regulating heat w/Buderus gas boiler

    the first two things that come to mind are the concrete slab acting as a cooler for the room. and the second thing is the location of the thermostat. is it close to an exterior wall, is it on an unusually warm interior wall?

  4. #4
    Join Date
    Feb 2010
    Location
    South*East
    Posts
    1,183

    Default Re: regulating heat w/Buderus gas boiler

    Quote Originally Posted by MLB Construction View Post
    the first two things that come to mind are the concrete slab acting as a cooler for the room. and the second thing is the location of the thermostat. is it close to an exterior wall, is it on an unusually warm interior wall?
    When the heat loss was done to determine the amount of baseboard needed to heat the room the loss from the slab should have been part of the calculation. There is not enough baseboard in the room.

    John

  5. #5
    Join Date
    May 2008
    Location
    New England
    Posts
    113

    Default Re: regulating heat w/Buderus gas boiler

    There's baseboard on every wall possible - cuz there's also a fireplace (there's baseboard next to fireplace), sliders (there are baseboards on either side), the main door & a window (baseboard below window), and the open entry to main house. Thermostat is on "interior" wall near entry to main house. Room is wall to wall carpeting.

    When the room reaches 68, the baseboards are super duper hot (why too hot to touch). And this generally happens on the coldest of days (temps in teens), & during the wee hours of a.m. But when outdoor temps are in 30-40, the room temp drops to 63-66 and the baseboards remain luke warm.

  6. #6
    Join Date
    Jan 2012
    Posts
    5

    Default Re: regulating heat w/Buderus gas boiler

    I'm not a heating spe******t but had similar issues after our oil to gas conversion. If we went away for extended trips and set the house to 50-55 it sometimes took all day to raise the temp to 65 on our return. The radiators were sometimes just luke warm like yours.
    Learned that there is a "smart" controller that adjusts the water temp in the radiators depending on the outdoor temp. On a mild day the system only pumps warm water thru the radiators and then very hot on very cold days. If we came home on a 50 degree day the system didn't care that we wanted fast heat, it just moved warm water. If we happen to bump up the thermostat on a very cold day the house warmed up fast as you would expect.
    We had a service tech out (on a mild day by chance) and he temporarily disconnected the outside temp sensor. The system pushed piping hot water through the radiators which raised the house temp immediately.
    You may have an issue with your sensor. If it is located in a sunny warm corner outside it may cause your system to lower the radiator temp enough that it won't compensate for normal heat loss. See if a service tech can make an adjustment.
    I was ready to put in a cut off switch to the outside sensor to disable it when we needed full blast heat. We have since sold the house so I never tried it though. Good luck.
    Last edited by DIYPeter; 01-18-2013 at 11:57 PM.

  7. #7
    Join Date
    May 2008
    Location
    New England
    Posts
    113

    Default Re: regulating heat w/Buderus gas boiler

    The logomatic computer's outdoor sensor is located on the northeast side of the house. So it gets the early a.m. sun (if sun happens to be out).

    We're unable to "force" the temperature to rise in this space. We never ever ever had to leave a thermostat set @ 68 before (have owned other houses w/other heating systems), but found if we left this room set @ say, 64 during the night/daytime, we'd come home from work and it may be 59 in the room. Brrrrrrrrrrrrrr. And we were told by HVAC guys never to "bump it up" more than 2 degrees. Bumping up the thermostat doesn't have any impact.

    So to compensate for the "as much as 5 degree drop", we decided to set @ 68 and leave it. Again, seems like a tremendous waste of gas when we set @ 68, and the system never reaches 68 for hours/days/weeks. Then again, we've never seen the kind of savings we were told this unit would save.

    This a.m. the room is 65.

    I just don't understand why when the room does reach 68 (and why at the most inconvenient times - like middle of the night or wee hours of the a.m.) and the baseboards are super duper hot when it does reach 68, why doesn't it maintain it on a regular basis. Do I have to set the thermostat for 74, to allow for a drop to 68?

  8. #8
    Join Date
    Jul 2009
    Posts
    143

    Default Re: regulating heat w/Buderus gas boiler

    crylakel:

    I would recommend you contact Buderus directly at 1-800-283-3787 in Londonderry, N.H., explain the problems you're having with the logamatic system and ask to speak to a member of the technical staff, and ask them to intervene directly by sending a knowledgeable logamatic technician to your home, or sending one out from your locality at no expense to you; when you speak to Buderus, have ready for them the model # of your boiler and the model # of your Logamatic Set-Back control.

    Clearly, the tech you had over the house is without a clue---you have every right after the expense you expended to expect an expensive heating system to perform a lot better than it's doing now.

    As DIYPeter noted, you may have a "basic version" of the logamatic that is narrowly (and mindlessly) programmed to read whatever is the outside temperature, and order the boiler to produce a low boiler water result of approx 120-130 degrees---while your boiler is capable of producing 180-200 degrees hot water, which is often needed for an individual room in a home situation like a family room, the logamatic outdoor control won't allow the boiler to produce that temperature hot water unless the outdoor temp is below zero---as noted below, there should be a way of resetting the BASE POINT of your Logamatic to increase the boiler water temp to 140 degrees, so hotter boiler water will be allowed to flow thru the family room baseboards.

    The only solution may be to have an offset module, or a cut-off switch that can modify the outdoor reset logomatic & send 170-180 degree hot water to the family room baseboards when needed, and leave the rest of the house set at the lower temps; there is a note in the Buderus literature below that the BASE POINT of the Logamatic (AM10) can be reset up to 140 degrees--if you have this model Logamatic, this could be a simple fix in itself without adding any additional modules.

    If you have the Logamatic 2107, check the 3rd site below & scroll down to Section 6.2 "Insufficient Heat" call to see if you can reset the water temp BASE POINT higher on your system.

    Also Google "logamatic problems" for numerous other cases of problems with the logamatic outdoor reset system.

    Thus your present logamatic may be able to be reset, or you may have to add a logamatic ROOM SENSOR---see 1st site below.

    There are several downloads at the site below explaining the Logimatic controls and Room Sensor Modules.

    Please let us know how you make out with Buderus and subsequent tech support on this issue.


    http://www.buderus.us/products/contr...atic-2107.html
    http://www.buderus.us/support/downlo...upport-t4.html
    http://www.buderus.us/files/20100623..._06%202010.pdf
    Last edited by Pelton; 01-20-2013 at 12:15 AM.

  9. #9
    Join Date
    May 2008
    Location
    New England
    Posts
    113

    Default Re: regulating heat w/Buderus gas boiler

    The logomatic model is R2107.

    We know its a rather "complex" system. Have seen techs come out (from HVAC that installed), unsure what to do when they hear the problem. One told us the family room thermostat is also controlling the heat in one of the upstairs bedrooms (which makes no sense @ all since the two upstairs bedrooms are part of the "main house" zone).

  10. #10
    Join Date
    May 2008
    Location
    New England
    Posts
    113

    Default Re: regulating heat w/Buderus gas boiler

    To follow up on heating issue w/Buderus, was advised to contact the HVAC installers since the system was still under warranty. But I was prepared this time with the info shared here. As soon as HVAC arrived, could tell they really didn't believe "heat" wasn't heating sufficiently in this one zone. Tried to explain how we were tracking the temperature for months - how room only reached 68 in Jan (and then only in middle of night & early a.m. - after that, room temp would drop off as outdoor temp increased). I said we thought the problem was w/base point - how it needed to be reset, but they quickly dismissed.

    About 1/2 hr into visit, HVAC came up to increase t-stat in main house zone (always set @ 64), but I told him what's not the solution cuz I knew sometimes that would force the other zone to "match", but it also meant we'd be heating two zones when we only wanted one zone @ 68. So he returned t-stat to 64.

    Finally they said it was the "power head" problem - it wasn't working, and they needed to have part delivered. Not sure what a power head is - something about when other zones called for heat, the family room zone wasn't able to get what it needed to heat up just that space. something wasn't opening.

    So because this system is under warranty, they did replace for free (did try to charge a dispatch fee, but I had it waived).

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •