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Outdoor Reset Setup - Am I on the right track??

HeatingHelpHeatingHelp Posts: 361
edited October 21 in THE MAIN WALL
This discussion was created from comments split from: Outdoor reset and homeowners.


    So here is a post for what I am kind of dealing with. First my contractor didn't want to put the ODS on. Tells me it isn't needed. Then he doesn't set it . Because he doesn't know how. from what I gather. Here is the manual read it and figure it out. Now I have a Navian NCB-240E. It actually isn't cold enough but for 2 days. That my heat was able to be used. Until 3 weeks ago. I didn't even know the ODS wasn't turned on.
    So into the manual I go and onto all these sites and reading whatever I can. I was a Automotive design engineer with a degree in Mechanical engineering. Before I switched professions. My life started with slide rulers and gradually progressed into a calculator.
    So I have this boiler put into my High Ranch house. Which was raised 10 ft due to hurricane Sandy and still not finished. I was living in a trailer in my backyard for almost 5 yrs. When they finally started the lift on my house. My boiler was just changed from a Quietside 120a. Because of the last storm. Hurricane Asiasis dropped a tree on the power lines and sent a stray current through my house. Destroying every GFI, Along with my Boiler, Handicap lift, Microwave A/C and Dishwasher. Plus the tree falling on my 2 month old used 2011 Ram 1500 that I only drove 125 miles. Since it sat in my driveway from March till July. Since the corona virus started and I couldn't register it till July.

    Back to my house My home is a split level high Ranch. Is still being elevated due to Sandy. I used Fox Blocks for the foundation and the house is elevated about 10 ft to the floor that was ground level. I have a 2 zone system with the first floor 120 sq/ft. Plus the boiler room about 80 sqft. Which has a sink, washing machine and dryer in it. Using a Slant fin 12 ft base board in the 120sqft room. There is a sliding rear door in that room. That is zone 2. The rest of the house is zone one which is 3 floors Living room, Dining Room, Kitchen and front door entrance with small hall. This is where a mechanical thermostat which is going to be changed to digital or a Nest in the hallway leading upstairs. Next floor is 2 bedrooms and bath with Jacuzzi tub and shower. Top floor is Master bedroom with walk in shower. Total convection radiator's, length is about 48' mono flow system. But my Bathrooms are a 2' and 3' slant fin base board instead of radiators. My Garage was heated with a slant fin 18' ft baseboard. Before it was raised, but I cut that out of the zone 2.
    I am going to put Little Giant Gas operated ceiling unit's or Modines at about 30,000 or 45,00 BTU to heat what is the garage. Which is about 20x24 sqft. Also now a 20'x 24' storage space with a 18 FT high Ceiling. The garage ceiling is now almost 22' high. The storage space use to be a unheated 20'x24' 3 ft crawl space. Raising the house added 1,100sq/ft. So my whole house is 2,2oo sq/ft with a not so well insulated unusable attic. But the rest of the house has all been redone with R-38 fiberglass with paper for exterior walls 12" thick. Then new siding with 3/4 Polystyrene insulation and Certainteed Cedar impressions vinyl siding. Outside of the foxblocks have acrylic stucco. Also my ceiling in the storage room has R-38 in the ceiling with 1/2 pink board and then 3/4" drywall. I have smart flood vents which 4 are solid insulated, and 4 are vented to open and close depending on temp. So I could see where my heat loss is going to be. Besides from the garage door like usual. I also have a full pressurized fire sprinkler system through the whole house. Not my idea but the towns requirements. So I must heat the garage and storage space, or I might have problems if it is a very cold winter. Some windows have been replace some have not but they are dual pane argon filled double hung. some are Anderson windows. The Garage has new 6ft window. The storage space has 2 new 6ft windows.

    That's the story in a nut shell besides asking the question about the outdoor sensor setup. I do not think I am over sized from what I have gone through with winters out here. I just want to start with default settings on the outside sensor. Till I really understand this boiler, and setting it up for custom needs if I have to. So I finally got around after reading and re reading the manual. Went and activated the ODS..

    Next part of thread coming up
    Never forget 09-11-01 FDNY/EMS/NYPD/PAPD/PENTAGON and those still dying.
    I am on pg64 at 11.5 setting the parameters. and hold Diag button for 5 seconds to enter Special Parameter mode.
    2. press + or - buttons to move to "1.PARand enter password. 1234.
    3. just tells you press Mode to enter the 4 digit code
    4. Press Mode when done. 5,6,7,8 just tells you how to move the buttons to move between modes. how to save settings and what happens how to exit by pressing the Reset button twice.

    Then the guts of the setting programs
    A. Config the outdoor Reset Control Mode
    Box shows A.o.R.C for enabled

    B. setting heat Load for the Outdoor Reset Control Mode.
    I have convection Radiators on the zone for the Outdoor sensor. So do I use 1. Finned Tube Baseboard or 6 for Radiators?
    This is where I get really confused Cause are the rest of these settings for #7 Custom Mode? Or do I have to mess with these. I know some say for custom settings.

    C. Setting lowest Outdoor Temp Default is 14*F . I know it might get that cold or colder come Jan-March

    D. Setting Highest Outdoor Temp. I figure that should stay at 70*F

    E. Setting Boost Interval Time. This I am not sure about. OFF is (0), then it says 1-120 min
    F. Setting the Max Heat Capacity for Space Heating. It says 100 is default. Setting Range 50-100%. I figure 100% might be to high for condensing and to may cycles?

    G. Setting Pump Freeze Protection Temp. Default is 50*F. Setting Range 43-50*F

    H. Setting the Anti-Fast Cycling Time. Default is 3 min. Setting Range 0-20 min.

    I. Setting Pump Overrun Time. Default 40 min. Settings 3-40min.

    J. Setting the DHW Max Heat Capacity. Default is 100%. Setting Range is 50-100%. I figure leave it at Default.

    K. Setting the DHW Wait time. Default is 5 min. Setting is 0-20 min. (I was told to set this to stay on longer. So the 3 way valve doesn't operate back to Space Heat to fast when using domestic water. That is saves wear on the 3 way valve?)

    L. Setting the Burner off Temp. 4*F is default. Range is 0-54*F.

    M. Setting Burner-On Temp. 5*f is Default. Range is 5-54*F

    N. Setting Supply Absolute Max Temp/ 180*F is Default. Range is Min set-point +36*F to 194*F (It says this for custom mode use only)

    O. Setting Supply Absolute Min Temp. Default 104*F is Default. But it says 77*f to [MAX Set-point - 36*F]? How can this range be less the the Default. (Again Custom Mode?)

    P. Setting Return Absolute Max Temp 149*F is Default Range [MIN Set-Point + 18*F] ~ 158*F (Custom Mode)

    Q. Setting the Return Absolute MIN Temp. Default 86*F. Range 68*f ~ [Max Set-point - 18*F (Custom Mode)

    R. Setting automatic Make-up Water Feeder Pressure/ AWS Default is 12 PSI. Setting Range 12-30PSI ( I figure 12 PSI is ok)

    S. Setting Initial Start-up #. Default:0 (Auto setting: Total installation #/ 2, Max 3). Setting Range 0-16 ( This is if you have more then one Unit?)

    T. Is for Cascade Protocol. Which I don't have since I only have one unit.

    U. I think is if you have a remote control. Setting Zone Controller Communication. So that stays off for Smart Zone +Controller connected by ready link.

    V. Setting Minimum Heat Capacity for Space heating. Is Default just says (%) but setting range is Minimum - 40% (Is this part of Smart Zone set-up or Custom Mode?)

    W. Setting Minimum Heat Capacity for DHW says same thing has V.

    X. I guess are for Navi-Link Connection which I don't have, So set to No

    The main question is. If I set A to 1 or 6. Do I need to mess with the rest of these. Except which say are for Custom or the Link setup ? Or Does 1 or 6 automatically set up defaults for the rest of the settings?

    So about 4 days ago it went down to about 45*F. Had zone 1 tstat set at about 70*F, My zone 2 down at 65*F. I had the door between those rooms open. It was about 67*F down there. Also 67*F through the rest of the house. But my daughter had one of her windows opened about 2" when I looked. Because I felt the draft coming from under her door.

    I didn't set the ODS at that time yet, and I didn't stay down stairs long enough to see if the boiler was modulating. I do know it was holding the inlet at about 138*F, and return was about 141-149*F. They were both set at the default. That is if I was looking at it right. The PSI was holding at about 30.2PSI. I was only down there for about 10 min and the Space heating Icon was on and the Combustion light stayed on also. But both zones were not on together. The zone 1 was operating.

    So the next day I got the guts to set the ODS and I put B at 1 for now. I left all other things stay at the default for the Finned Tube Baseboard. Supposed to get about the same temp, and I will spend some more time downstairs. If I get up at 3am again. At least I feel comfortable using the settings. It didn't make much of a difference. The inlet temp was still about 138 and outlet went to 145.
    The next thing I did was set B to #4 which is low Mass Radiant. My inlet went to 100 and my outlet down to 138. Then I made setting F which is Max Heat capacity from 100% to 70%. My my inlet went to 85 and my outlet went to 120*F. It modulated and sounded like it was doing what it is supposed to. It cycled the tstat switches but the flame stayed on through the night. out side temp about the same. Today it is 12:30am and it says it is 61*F on the ODS for outside temp. My windows are opened n heat coming on t'nit. Or the rest of the week. According to the weather forecast.

    I am sorry this is so long But am I on the right track? I know it is nowhere near Jan-March temps around here So I know I am going to have to play with the settings. Without doing a custom setting and first using defaults. Am I doing the right thing until I learn about setting Burner off temp setting, Supply absolute Max and Min and Return Max and Min temp settings. Then if I pit 2 digitals or Nest Tstats on am I going to be re thinking these curves?
    Never forget 09-11-01 FDNY/EMS/NYPD/PAPD/PENTAGON and those still dying.
    So I found this article maybe if someone else is having problems it might help. Seems to help me understand some of what I need to know
    Never forget 09-11-01 FDNY/EMS/NYPD/PAPD/PENTAGON and those still dying.
    I was wrong my B setting on #4 only allowed my supply return water temp go to 102-107*F. That was with a 49*F night temp. I put B to #6 for radiators and my water outlet temp went up to 138-149*F with one zone and seemed to normalize at 135*F. When zone 2 kicked in outlet water supply temp was 131*F. The problem was It never turned off at all. I am not only talking about the gas but also the zone pump. I am sure it is supposed to cycle at least 3 times in a 24hr period. Also the zone pump should turn on and off. If I am explaining it right.

    It got so hot I had to open windows. But if I put my tstats below the running point of 70*F. For a zone to cut off. The house gets to cold before they turn the zones on again.
    Then it seems if zone 1 does not turn on at all, my zone 2 will not run either. I know the ODS only controls one zone, but all the tstat's operation is like a switch. So even if zone 1 isn't on once the zone 2 tstat closes the boiler and the zone pump should run?

    I hope to have a Navien tech come and look to see if I just need custom use and the other stuff tweeked / Or I need to reallt replace my old Tstats with digital or Nest which s what I was going to do once I had the money.
    Never forget 09-11-01 FDNY/EMS/NYPD/PAPD/PENTAGON and those still dying.
    So yesterday and the day before It was 32*F here the last 2 days 11-17-20 with the wind blowing it showed 29 to 30*F. I had the upstairs zone 1 set at 72*F on the Nest E and the downstairs set at 69*F on the other Nest. Neither stat in Eco mode, and I had short cycle problems. With the Heat load set to the default #1.
    So I did a custom setting.
    L: left at 4
    M: left at 5
    N: 138*F supply Max Temp,
    O: 102*F Supply Min Temp,
    P:120*F Return Max Temp,
    Q:102*F Return Min Temp,
    F:60% for the Max heating capacity. I started at the 80% but I was still going to high on my supply and return temps. At 60% I was sitting at 130*F to 133*F on the Supply. But it did go up to 138*F a couple of times but didn't stay there. On Return 120-126 and was pretty constant. I was able to get to 75*F while I was allowing it to run and see if it would short cycle. But it was hard to stay there. But It didn't cycle but modulated for 10 hrs that I let it run it stayed on. Except for 2 times the burner went off. I had condensation fill up and pump out of my neutralizer. So I figured I am in a pretty good zone.

    I then lower my stats on both zones to 71*F and zone 1 cuts off after a while. Now here is my problem. On Zone 2 the stat stayed on at 71*F and all of a sudden I am cycling about 5-7 times in 45 min. With the Supply water temp staying within 136-138*F, But my Return water temp kept going above 127*F. It would come on when return water went to the 120*F mark. Zone 2 has a 12ft slant/fin fine/line 30 baseboard against the exterior insulated wall. I figured I need 1,632BTUs for the 1,016 cuft room?

    With zone 1 on and zone 2 off, no problem Supply 130-132*F and Return is staying at about 122*F. No cycle problems. What can I do to have zone 2 not cycle. Also it says I should be able to get my Supply Max water temp between 36*F to 194*F. Why cant I get it below 138*F. Do you think if I went to 50% on my Max heat capacity setting this would help? Been messing with it almost all day and its 28*F outside now. I take that back it started to really short cycle on 3 min off 5 min. If zone one or zone two was on.

    To get my house heated comfortably, it seems I can't use low temp heating water. Or the reality is this unit is way over kill even at 50% Heat Capacity. For now I put it back to what the tech put it at. It was in the 40's* and when it ran I didn't have short cycle. But more then I want it cycling anyway. It is doing about 168 *F supply and about 148*F return. So I have a 20* deltaT if I am saying it right. My T-Stats are in Eco mode and the house is comfortable. Upstairs 69*F and Downstairs 66*F. Outside temp is 47*F. Last time the unit ran was 4 hrs ago for 20min. upstairs. Downstairs last time it ran was 11AM for about the same time.

    Maybe I should have gone with a smaller unit and I would not be having this problem. Maybe if I put the Modine Lodronic Hydronic heaters one in the Garage and one storage area which is also my shop. It will allow me to run at a water return of 120*F without short cycling and a lower water supply long enough to heat the house. Or I am setting myself up for different problems. I need to heat an extra 8,934 cuft since my house was elevated after Sandy.
    Never forget 09-11-01 FDNY/EMS/NYPD/PAPD/PENTAGON and those still dying.
  • GilmorrieGilmorrie Member Posts: 127
    This thread has gotten a bit out of hand. Can you just ask one question at a time? And only provide the details required for that question.
    edited November 20
    ok sorry tell me what info you would like to figure out my reset curve?
    Never forget 09-11-01 FDNY/EMS/NYPD/PAPD/PENTAGON and those still dying.
  • Steve MinnichSteve Minnich Member Posts: 2,617
    edited November 21
    Outdoor design T
    Indoor design T
    Supply water T @ ODT high
    Supply water T @ ODT low
    Author - Hard Knocks: My Life Inside Boiler Rooms
    PHC News Columnist
    Minnich Hydronic Consulting & Design, LLC
  • Steve MinnichSteve Minnich Member Posts: 2,617
    edited November 21
    Outdoor reset parameters/curve is usually a moving target. You may not get it right the first time. Much of it depends on who’s living in the building. 

    Some prefer as much energy savings as possible while others require a trade-off between savings and comfort. 

    If you want to be aggressive and shooting for max. energy savings, set your outdoor design temp. a little higher than the standard ODT. Or, lower your supply water temp at ODT. Or, do both and adjust accordingly. 
    Author - Hard Knocks: My Life Inside Boiler Rooms
    PHC News Columnist
    Minnich Hydronic Consulting & Design, LLC

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