HVAC 2.0 Diaries

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March 28 2012


  • 1:45pm- outside air temp 67°, outside RH 36%. Turned off desiccant wheel
  • zone 1 @ 69.9°, 50.5% RH
  • zone 2 @ 69.4°, 52.5% RH
  • zone 3 @ 68.9°, 52.9% RH
  • zone 4 @ 69.6°, 55.0% RH


March 15 2012


  • Dehumidification running at 8AM. Water temp leaving Altherma is 75°F. Earthroom is at 75°. Setting was at 50%, raised to 55%RH with differential of 10%.


March 8 2012


  • Notice Altherma running in cooling (dehumidification mode). Annex side at 50.8%rh. Havent checked when altherma started. Checked temp readings on altherma- not putting out cold water, but hot. Must verify. Checked earthroom temps, not rising as expected when making cold water. Raised setpoint to 55%, stopped cycle.
  • At same time, noticed erv on high- co2 levels at 860ish, meeting in conference room in progress. Still need to check why this is not counter balanced at all by other empty offices.


Feb 9 2012


  • Need to get logic modified on earthroom fan to have fan off if altherma is not running.
  • Need to write logic for operation of damper 2 to avoid coil freezing.
  • Need (adjustable) differential for altherma heating or cooling the tank. Current set point causes Altherma on/off short cycle.


Feb 1 2012


  • 48 degrees out. Shut off Altherma to observe panel affect without altherma running.
  • 4 PM panels off. restarted altherma. Tank temp reading 99.2°
  • second day in a row where panels run but t2 temp reading goes down. Panel water reached a high output somewhere around 120°


Jan 31 2012


  • 50+ degrees out. Shut off Altherma to observe panel affect without altherma running.
  • Checked previously on bypass line taking some of the panel water back to the panels, not to the tanks. With Altherma off, pump 2 does not run at the same time as pump 9. This may be reducing the effect of pulling water through the bypass? Current T2 is 94.3° and T1C is 94.8°.


Dec 29 2011


  • John Fish removed EVRISKO sensors and programmed SpinWave.
  • Changed logic for Valve 25. Rotated motor on valve 90°, verified rotation and orientation of valve. Valve 25 is now open by default and only closes on a dehumidification call with valve 19 opening. The startup delay for the Altherma for heating and cooling the tank was removed, since the valve is already open when the Altherma starts.


Nov 22 2011


  • 6:30AM 4 sensors not communicating with JACE


Nov 21 2011


Notes from LL Catey:

  • 9:15pm - Noticed P-2 was running in unoccupied mode with no apparent call for it and nothing else running. Looked like it "flickered" off then right back on.
  • Looked at trend history, and P-2 was cycling on and off frequently over a few hours in the evening, but Altherma and P-3 were not showing any trend points in the "on" mode, so not sure why P-2 was coming on and off.
  • Trends indicate that the Altherma has not run since November 10, 2011, but it has been known to be on since then, so it appears that perhaps the trend points for the Altherma are no longer being picked up and/or stored in the history?
    • Question: Are Altherma points trending correctly?
  • Observed further and saw that Altherma was actually cycling on. However, when it cycled back off, P-2 only went off for a second then came back on (short cycling).
    • Question: What is the logic for P-2 to start and stop based on Altherma charging tanks?
    • Question: Does that logic have any sort of time delay or a temperature dead band built in to prevent short cycling? If so, how much?
  • On the graphics, the "Altherma HT Enable" point went to "enable" presumably when the Altherma was on, but the "P8 Altherma HP" always indicated "off". I don't believe I have ever seen this point as "on" before.
    • Question: Has P-8 status interface (current sensor or status point) been checked for proper setup and response?
  • 10:40pm - Saw Altherma Heat Enable point on Piping View enable, then disable 2 minutes later.
  • 10:43pm - Saw Altherma Heat Enable point enable, then disable 20 seconds later.
  • 10:47pm - Altherma Heat Enabled, disabled about a minute later.
  • Tank temperature is fluctuating frequently/rapidly around 94.8, 94.9, 95.0 degrees F.
  • It appears that the Altherma is also short cycling, possibly based on trying to maintain tank temperature?
    • Question: What is the logic that enables and disables the Altherma?
    • Question: Does it have a time delay or temperature deadband associated with it? If so, how much?
    • Question: What is the minimum run time and the minimum off time programmed in the Altherma packaged controls when it was started up?
  • L. Catey set the "Tank Low Limit SP" for 97F instead of 95F, and P-2 came on and stayed on immediately; Altherma Heat Enable came on about 1-2 minutes later and stayed on. That does seem to indicate that the deadband or time delays may be missing or inactive.
  • Set tank low limit SP to 94F since next few days temperatures are forecast to be mild with two sunny days and equipment is short cycling so frequently.
  • Pumps and Altherma immediately stopped.
    • Check sequence while on site to see how Altherma reacts to disabled command. Does P-8 run after receiving disable signal until Altherma unloads and shuts down? Shouldn't P-2 also have some short time delay after Altherma disables to collect the residual heat that comes off the Altherma as it is shutting down rather than a hard stop of P-2 right at disable signal?
  • Sent E-mail to Joe and Tom with above observations.


Nov 18 2011


  • 6:30AM- tank at 84°, floor supply at 82°, Altherma enable, but earth room at 53°, earth room fan not enabled, not a good sign.

Got on site at 8AM, altherma in low flow default.

  • Sensors continue to drop off, sensor 4 out around 3PM. Different sensors lost signal Tues, Wed and Thurs this week.


Nov 17 2011


  • Wired tstat reading 71.4° in design studio. Wireless sensors 68.3°. Moved wired unit back to mezzanine at 12 noon.


Nov 9 2011


  • Signal dropped on sensors TH1. TH3, and TH4 around 4PM. Batteries changed in sensors TH1 and TH3, sensor TH4 switched on and off. Batteries changed in TH2 on 11/8.


Nov 2 2011


  • 6:00AM- notice 3 of the room sensors dropped out overnight.
  • Sensors are highlighted yellow on web page. Reset sensors at 8:10AM- no change in status on webpage.


Oct 28 2011


  • 11:36 PUMP 9 STARTED
  • 11:41 tank low water level


Oct 25 2011


  • 6:45AM ventilation erv running mode 5. Schedule calls for 7AM start.
  • Basement exhaust fan operating at 6:45. Altherma is not running, fan should have stopped? Manually turned off power to fan. Turned back on but it did not run. Need to understand deadband.
  • 4:50 PM. Unable to change 'outside air changeover temp'. This was being used to force damper 3 open based on outside air temp.


Oct 24 2011


  • Added water at 11:30AM, to full tank. Panels running with no low water level alarm.
  • Water temp from altherma into heat exchanger- 96°, 79° water going back to altherma. On tank side- 84° water coming from tank to exchanger, 90° water going back to tank.
    • Altherma Side: 500 x 7 gpm x (96 - 79) = 59,500 Btu/hr
    • Tank Side: 500 x 20 gpm x (90 - 84) = 60,000 Btu/hr
  • With the tanks in the 90F - 100F range, it looks like the Altherma by itself is raising the tank temperature approximately 3/4 of a degree per hour, looking at the trend graph.


Oct 23 2011


  • Solar Thermal - Added water to system on Friday, 10/21/11 and low level alarm is on again even though solar system is off.
    • Recommend measuring water added to system (inline garden hose meter could be used).
    • How much evaporation is normal for our system? (Alan?)
    • Could tube where low alarm float enters tank have cover fit around it to reduce evaporation if it is a problem?
    • Are there other openings to the system?
  • Zone 4 Annex radiant floor heating came on for first time in a long time Saturday, 10/22/11 around 8:30 p.m., but it was because the zone stat lost communication. All 4 stats dropped communication between 8 pm - 9 pm. So, zones heating now even though stats are indicating higher temps than unoccupied setpoint.


Oct 17 2011


  • System Setup & Overrides set for large event (Tom Bradley Celebration of Life)
  • Solar array, Zone Controls left in automatic operation with no overrides
  • Ventilation system setup with overrides:
    • Occupied mode by time of day schedule (ERV on, Booster Fan on)
    • Space dehumidify enable setpoint overridden to 90% to prevent Altherma from coming on (still working on low flow tripping of system)
    • Carbon dioxide DCV enable setpoint overridden to 300 ppm to bring in more fresh air prior to people arriving (ERV on high speed)
    • OA changeover temp set for 60F to open D-3 to decouple ERV supply and booster fans until programming change is complete (reheat call)
    • Booster Fan F-3 on high speed for reheat call but commanded back down to 7 volts speed signal to prevent excess noise during event, causing F-3 supply to match ERV supply F-1 essentially; didn't really need reheat, just needed D-3 open
    • One window open throughout event; window at end of corridor by enclosed offices with noticeable breeze
    • Opened front awning window by entry door for a moment, but was too noisy to leave open
  • Outside Air Conditions
    • Temperature Range: 45F - 61F (mean 52F)
    • HDD: 12
    • Dew Point: 35F
    • Humidity Range: 32% - 71% (average 53%)
    • Barometric Pressure: 28.74 in.
    • Wind Speed: 13 mph (WSW)(max 21 mph; gust 31 mph)
  • Observations
    • Trend charts for day are available in the Cx Record under 2011_10_17 Fall Shoulder-Large Event
    • Zone temps and relative humidities remained good throughout the day (approx. 67F - 69.5F and 50% - 64% RH); observed approx. 1F rise in occupied area between 11am-1pm
    • CO2 peaked near 1400 ppm after lunch was served (range approx. 430 ppm - 1387 ppm); started dropping off around 2:15 p.m.; was still around 575 ppm the next morning
    • CO2 related to 200 people being in space and gel burners warming food in the southwest area of the historical building
      • ASHRAE and OSHA standards limit CO2 to 1000 ppm
      • General stuffiness and odors may be experienced from 600 - 1000 ppm
      • General drowsiness may be experienced from 1000 - 2500 ppm
      • Adverse health effects expected from 2500 - 5000 ppm
      • Maximum allowed concentration within an 8-hour working period is 5000 ppm
      • Extreme and dangerous concentration levels start at 30,000 ppm (causes death at 100,000 ppm or higher)
    • General opinion was that the space was very comfortable and did not feel stuffy at all
  • Additional Thoughts for Future
    • Have indoor plants that use up the CO2
    • Open windows on Green Alley side and observe noise; open windows up high on mezzanine
    • See if speed controls on ventilation fans can be tweaked a bit higher for events with more people and/or food warmers


Oct 7 2011


  • water temp from panels at 130° most of day
  • 7PM- forced pump 9 off by increasing solar array dissable setpoint and eliminating cloud delay. T1c had reading of 114°, and T1b had reading of 112°. Logic should turn this off if water entering panels is hotter that water leaving panels.


Oct 7 2011


  • Piping View-
    • T8 and T7 identification is incorrect. The temperature readings are in the correct spot.
  • Zone Control Data-
    • Floor hw supply temperature and floor hw return temperature readings are backwards. the supply is the hotter (T8) number.
    • Zone Heat/Cool scheduled says 'unoccupied' It is in the occupied hours range.


Oct 5 2011


  • 6 AM. pump 3 and 5 ran all night.



Oct 5 2011


  • weather info from nws stopped responding yesterday. Temp reading has remained at 45°.
  • zone heating calendar during occupied hours is reading 'unoccupied' set point, though calendar appears to be correct.
  • 8:37PM- pumps 2, 3 and 5 running. sensor reading not low enough to call for heat. used 'emergency active' on pump 2 to stop. cannot get this control drop down on other pumps. 3 and 5 still running.



Oct 3 2011


  • Zone heating on at 7AM. Water in exchanger started at 107°. Room sensors at 67°.


Oct 2 2011


  • Solar Thermal Collectors
    • Sunny ... somewhat!
    • Tanks = 88F ... why so low? Did heating on Friday that used heat from the tanks.
    • Array Out = 113F ...noticed Core Air temp = 116F...outside air around 54F.
    • Still maintaining a 23F rise from in and out during sunny portion of the day.
    • T3 (at exchanger) reading was low today ... 77F (?) I think I saw. (Tom)


Sept 27 2011


  • Solar Thermal Collectors
    • Sunny ... hooray!
    • Tanks = 92.8F
    • Array Out = 106.9F @ 11:27am...noticed Core Air temp = 86F...because outside air is 54F.
    • Still maintaining a 17F rise from in and out.
    • T2 reading at 93.9 but T3 (at exchanger) reading is 103.8?



Sept 26 2011


  • Heavy rains in AM. Broken clouds later, did get some heating.
  • Noticed zone 3 heat running at 4:30. Changed temperature setting and setback t, did not shut off loop. Changed space heat calendar to Oct, pump 2 and 3 went off, pump 6 continues to run. Noticed while 2 and 3 were running, valve 6 did not modulate to get loop temp to 90°.



Sept 25 2011


2011-09-26 0145 Zone stats temp dropping out.png
2011-09-26 0137 Zone FPT Z2 Unocc Htg.png
2011-09-26 0223 OAT RH Last 7 days B'ham.png
  • Mainly cloudy...small amounts of sun.
  • P5 on at 1:00, there should be no call. P2 and P3 also on, set to 'emergency auto' and they went off. P5 did not. ***[LLC COMMENT] Zone stat temps dropped out to zero degrees a few times, so it appears that pumps came on because they thought the zones required heat when the zone temps went below the unoccupied heating setpoint. Problem appears to be with stat signal, and pump logic for unoccupied heating mode appears to be correct. See images at right.
  • Tanks @ 92.8F
  • Why is the humidity in the building so steady. It's been in the low 60'sRH for some time even though the humidity outdoors has been very high...tonight it's 71RH. It's been 91RH last week. ***[LLC COMMENT] Wondering what you were thinking it should be? Looking at 7-day history, RH fluctuated between 55% and 65% per stats. Three weeks ago, it was 50%, but the indoor temp was also 75F then, and now is around 69F-70F, so about the same moisture content. OA RH doesn't mean too much without also knowing what the temperature is since it is so relative. See history from Birmingham for OA temp/RH to get feel for that magnitude over the last week. Building materials absorb/give up moisture as content in air changes also. So if temp pretty steady, then RH likely to also be steady unless introduce big load in space. Seasonal moisture content change is pretty slow.
  • Annex continues to be 1F higher than the historic building. Assume it is the tanks losing heat.
  • Earth room exhaust fan status point needs to be added to history trending.



Sept 24 2011


  • P9 was not coming on as scheduled...programmed. Determined to be the "mode" it was running in. Joe set it to "emergency auto" to get it running. Need instruction on how to set these parameters on the "Piping Diagram" when logged in as the "Admin".


Sept 23 2011


  • Solar Thermal Collectors (@ 6:34am) RAIN
    • P9 off
    • Array Out = 72F
    • Air Core = 49F
    • Tank 1 = 93.4F
    • BTU Production
      • Daily (Yesterday)
        • Partially Sunny day: 2.4F tank rise * 4800gal * 8.33lbs/gal / 400 sf = 240 BTU/sf/day
  • Ventilation
    • Mode was correct: Unoccupied
    • Booster fan and ERV all OFF
    • Dehumidification Setpoint raised to 70%...to avoid it coming on with doors opening during construction
  • Earth Room
    • 67.1F
  • Altherma
    • Off
  • Zones
    • Annex is slightly high 70.9F vs. 70.1F than the historic zones: reason believed to be heat from tank room.
  • Follow-up Points
    • Need to get trickle loop logic for solar panels defined and working for the cases where the panels are not hot enough for the tanks but could heat the ground.
    • Need blanket for hot water tank.


Sept 22 2011


  • Solar Thermal Collectors (@ 6:20am)
    • P9 went off last night
    • Array Out = 73F
    • Tank 1 = 91F (Passed 90F!!!)
    • BTU Production
      • Weekly
        • This is 880,000 BTU's in a week.
        • This is 314 BTU/sf/day...which is on the low side.
      • Daily (Yesterday)
        • Partially Sunny day: 7F tank rise * 4800gal * 8.33lbs/gal / 400 sf = 700 BTU/sf/day <<== planned 750BTU/sf/day
    • Air Core = 49F
  • Ventilation
    • Booster fan was on all night- this is in mode 7 which calls for dehumidification
    • ERV was off last night
    • Altherma shows On? Trying to dehumidify. unit was off do to low water pressure.
    • 10:43 AM solar panels start- air temp-58, panel air temp 120, tank temp 90.9


Sept 21 2011


2011-09-26 0330 Solar Tanks FPT Fall Htg Up.png
  • Solar (Lunar) Thermal Collectors
    • Ran all night!! ***[LLC COMMENT]Check array inlet/outlet temp sensors when under load. Check array bypass line short circuiting. Check logic that starts pump to see relationship between core temp, array inlet, and array outlet temp and how they were programmed to start/stop array.
    • Tank 1 = 84F (about 85F from graph)
    • Array Out = 88F? (about 93F from graph)
  • Ventilation
    • Dehumidification was on most of the day
      • It produced water in the drain line!!
      • Graphing Indoor RH showed it was slowly going down.
      • Some risk if this can't keep up with very high humidity (91%RH today!)
  • Earth Room
    • Looks like Earth room hits 90F within 30 minutes of running
    • Issue with the exhaust fan turning on and off rapidly because it turns on at 90F and turns off at 89F. ***[LLC COMMENT]Spread out the dead band on heating and cooling end of exhaust fan operation. Also need to match exhaust volume with Earth tube design so incoming air is cooled/heated by ground as designed. Volume may be too high.
    • Not providing value because outdoor temp is 70F and earth room gets to 90F within 30 minutes.
    • Opportunity to do some "thermal pumping" in the shoulder seasons...heating 30 mins, cooling (dehumid) 30 mins, cycles.