Ontario Electrical Usage for Waterfurnace Premier Seems Way Too High

Discussion in 'Maintenance and Troubleshooting' started by Andrew Kulin, Mar 6, 2016.

  1. Andrew Kulin

    Andrew Kulin Member

    We purchased a cottage in early December with a geothermal heating and cooling system. The place has been generally empty most of the time and we have turned down the heat to between 50 & 55F when we are not up there, all lights are off, and there is for the time being no electronics or anything of the sort brought up. Total Electrical use was 1672 kWh in December (33 days, CDN$354) and 1824 kWh in January (29 days, CDN$407). We spent 3 nights up at the cottage during this time period.

    So besides the furnace, only things plugged in or running are the refrigerator, oven (clock timer only!), a dehumidifier in a cool crawl space (with sump pump which I don’t think has tripped on at all), an HRV, a heated water line to the well, and the hot water tank (which is also tied in to the geothermal furnace). All of these other uses use about 0.34 kW/hour usage based on my review of our hourly electrical use (we have hourly time of use “Smart” meters up here). I left the thermostat at 68F when we left last weekend to let me collect additional data with the house being heated at around room temperature without us being there.

    I think there is something seriously wrong with our system (Y/N?). We have arranged for a technician to come out early next week and look at our system (I understand this fellow is the original installer of the system from 2004). I’d like to know what things could possibly be causing our electrical use to be so high before he is on site so that he can check for those issues and what questions I should be asking him, what should be checked, etc..

    And here are my answers to the 10 questions from the troubleshooting checklist:

    1. Cottage – Haliburton, Ontario (purchased December 2015) – House is a Viceroy cottage built in 2004, 1911 sq.ft. main level (lots of panoramic windows facing south), basement (walkout) is 1568 sq. ft – about 2/3 of that is finished plus a 320 sq.ft. unheated crawlspace.
    2. Heat loss/gains – No idea at the moment – we have someone coming out next week to do an energy audit with blower test.
      1. We do have these observations to offer. We can tell how long it takes for the furnace to start back up again to heat after we have left the cottage and had turned down the thermostat. Took 29 hours to cool from 70 F to 50F with average outside temperature of 3 C (~37F). Took 10 hours to cool from 70F to 55F with average outside temperature of -10.7C (~13F).
    3. Waterfurnace Premier (circa 2004), Model No. P070TL111NBDSSA – understand this to be a 2 stage, 70,000 BTU unit, think it is about 6 tons for cooling
    4. Closed loop, goes out into the lake, about 400 or 500 feet out into the lake or so I was told. Lake is on average 28 feet deep to a maximum of about 90 feet deep
    5. Average cost = CDN$0.22/Kwh (includes electricity, delivery and other add-on charges and 13% taxes), Monthly Electrical Consumption:
      1. Dec 5 – Jan 6 = 1672 kWh (avg = 49.2 kWh/d when we are not there), 611.6 degree days (deg. Celsius) – CDN$354
      2. Jan 7 – Feb 4 =1824 kWh (avg = 56.6 kWh/d when we are not there), 717.6 degree days (deg. Celsius) – CDN$407
      3. Feb 5 - 28 = 1695 kWh (avg = 52.3 kWh/d when we are not there), 676.7 degree days (deg. Celsius)
      4. Feb 29 – March 5 = 639 kWh (avg = 106.5 kWh/d with thermostat set at 68F), degree days not available
    6. Fan running low speed: EAT = 62F, LAT = 82-83F. Fan running at high speed: EAT = 68F, LAT = 87F
    7. Fan running low speed: EWT = 27F, LWT = 24F. Fan running at high speed: EWT = 31F, LWT = 26-27F
    8. Percent of load to be covered and balance point – No idea at the moment
    9. Installers assessment of the system - To be determined when a technician is on site during March Break
    10. Projected operating costs, actual operating cost and previous heating and cooling costs
      1. Projected costs no good idea yet as we have no history of usage
      2. Actual costs – I have my costs above for ~ 2.5 months (winter) and previous owner left me with spreadsheet with about 11 years data (2004-2015) on kWH usage (they lived at place full time). The following is a summary of the previous owners’ data:
        1. Dec-Jan ranged between 72.5 and 145.6 kW/d (average = 118.2 kWh/d) (all 3 numbers are daily monthly averages over these months)
        2. June – Sept ranged between 17.1 and 54.9 kW/d (average = 35.2 kWh/d
    11. Other information:
      1. A single hot water tank is connected to the geothermal furnace
      2. Thermostat indicates Aux. Heat when we first get up there and set heat up to 70F from lowered setting of 50 or 55F. After temperatures have stabilized inside, I have checked thermostat randomly thorough the day and do not see the Aux. Heat icon turned on
      3. Aux. Heat must be electric – we don’t have gas/propane
      4. Electrostatic Filter is clean. I washed it about 3 weeks ago when we were up there (it was fairly clean when I washed it)
      5. I have attached a chart that plots electrical use of the furnace system against outdoor air temperature with the thermostat set at 50F, 55F and 68 F and no one present at the property. It only includes data from between 7 PM and 7 AM (night) so that effects from daytime heating are not present.

    Thanks,



    Andrew Kulin
    kWh vs Temp.JPG
     
  2. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    Cold ambient temperatures effect refrigerant pressures in the equipment. The usual minimum is 50F (10C) for equipment operations. If the unit is exposed to less, it can lock out under low pressure and you are now using emergency heat to do all the work.

    Is your unit in the unheated crawlspace and exposed to cold temperatures?
     
  3. Andrew Kulin

    Andrew Kulin Member

    No, it is in the basement which is heated.
     
  4. mrrxtech

    mrrxtech Member

    If I bought your cottage, I would 1) turn off the dehumidifier in the winter, 2) put a timer on the 220 supply to the water heater to allow it to come on a few times a day prior to when you normally get up in the morning, and other high hot water use periods, 3) check the water heater element thermostats for 122 to 125 degrees, 4) Open the breaker to the water heater when not using the cottage, 5) pull the fuses or open the switch if you have one for the hot water heater desuperheater pump to stop heating the hot water except in the summer when you want to reject the heat from the house into the hot water tank, 6) Turn off the strip heat to the well in the spring through first fall frost, 7) I don't recognize the HRV, but I would deenergize it when not needed, 8) I would evaluate why the water line is heat traced and figure out a way to bury it below the frost line and route it into the house 4 feet below ground level.

    Next deal with the geothermal unit when the technician shows up, or by using this site. As Earthbuoy said, the electric emergency/auxiliary heat is expensive, and uses every Watt of power that enters it as a 100% Resistive device, while a geothermal unit at a minimum uses 40% less electricity entering due to being made up of all motor/inductive reactance devices. 40% of the power goes back toward the grid saving you money.

    Your geothermal air differential temperatures are low at 20 degrees when they should be closer to a 30 degree differential. These guys will fix you up.
     
  5. Andrew Kulin

    Andrew Kulin Member

    1. Dehumidifier is in the unheated crawl space area, not the heated part of the basement. Do you still think it should be turned off?
    2. okay - will look into it
    3. hot water tank is factory set at 140F, there is no thermostat I can adjust temperature. A warning label says get trained technician to adjust, which hopefully the fellow next week can do for us (that was on my list of things to do already)
    4. Okay will look into that
    5. there are only 2 breakers on my panel for the furnace and so I do not think I can do this. One is labelled furnace compressor, the second is labeled furnace elements. I tried turning off power to the second one last weekend, and the fans shut down as well, so I left it turned on.
    6. Yes, definitely
    7. Heat Recovery Ventilator Unit. It is supposed to allow for air exchanges in a tight home, and takes heat from the outgoing air to warm up the cooler incoming air (I think)
    8. The basement crawl space is a crawlspace because of exposed, shallow granite that they probably did not want to blast during the build. The well is about 8 feet in front of the wall, and the rock is maybe 2 feet below grade here (you can see water line in photo, leaves house near the corner).
    When heating the place when we first get there (say from 55 to 70F), the Aux. Heat definitely comes on, and my electrical usage in the first hour has been in the range of 17 to 23 kWh (in the first hour) and around 8 to 15 kWh in the second hour, dropping off as the temperature in the place gets to 70F (between typically 5 - 8 kWh/hour while we are occupying the place with temp set at 70F).

    Thanks,

    Andrew
    crawlspace.JPG
     
  6. geoxne

    geoxne Active Member Forum Leader

    If you subtract out a conservative 20 kwh/day base load from your figures above you are using 1/3 to 1/2 the energy to heat unoccupied compared to previous owners occupied heat energy usage.
     
  7. mrrxtech

    mrrxtech Member

    1) Humidity in the air (that could condense on structural materials) is low in the winter, it's a summer problem only.

    2) Go on YouTube and watch how to adjust a water heater: https://www.youtube.com/results?earch_query=Water+Heater+Temperature+Adjustment. After watching if you feel this is out of your skill level, then ask a friend or Neighbor to help you with it. Some people replace their own heater elements & element thermostats when they go bad.

    3) Ask your Geo Technician to show you how to disable desuperheater pump in the winter months. My Trane has a fuse on the side of the pull out drawer that holds all the controls. I de-energize the 220vac to the Unit at the breaker, then twist the cap off and the fuse comes out with it.

    4) Heat Recovery Ventillator - You're right, it uses a heat exchanger to allow preheating/precooling incoming air to reduce the cost of changing out the air in your cottage. Do a check for Radon in the basement with an inexpensive test kit sold at Walmart or on ebay. If Radon is within government specifications on the test kit with the HRV off for the 3 or 4 day test period the HRV is for home air breathability only.
    The HVAC test you requested may include an inleakage test. If it shows excess inleakage then you don't need the ventilator fan. If you like using the fan, turn it off when you leave the cottage for extended periods. It won't take long to change out the air in the cottage when you arrive & put it back in service. Also it's not needed when the house is open.

    5) Tough break on the granite being at 2 feet below the surface, that would make trenching an issue. On the bright side, you won't have problems with the foundation/footer shifting on that kind of base material.

    6) To avoid the use of resistive heat in the aux mode, you can raise the thermostat setting 2 or 3 degrees staying below the Aux Heat mode, and slowly raise the temperature over a few hours. I know people who don't want to do anything but live in a house. They pay the electric company. I prefer to save money which will be needed elsewhere.

    7) It would be wise to get an estimate on this HVAC work you requested, then get 2 more estimates and some referrals. When I invite someone to my property, I need to have in writing what they are doing to do and for how much. If not, the Contractor scopes out how much money he thinks I have and makes like a thief at time to pay him.
    This is a real issue. That backhoe job I hired my Wife's friend to do, went from $35 an hour to $125 per hour 17 hours later when time to pay up. I paid him then nailed him (used the laws, State Departments, IRS and threat of court) and got my money back.

    Excuses for theft: "I need money to pay for my recent open heart surgery bill", "I have to make my money in the summer months", "Freon is real expensive". The truth is they are greedy and can put a lien on your property if you don't pay what they want, so you will have to pay then go on the offensive to recover your money. The Sheriff said I shouldn't have paid the bill. He was wrong, a lien is hard to remove from a deed when placed by a contractor, and it requires no evidence on their part.
     
  8. Andrew Kulin

    Andrew Kulin Member

    Does anyone have any thoughts about why my geo furnace is using so much electricity and what things could be at play and looked at when I meet the technician up there on Tuesday? And any specific, techical questions to ask the fellow when I have the opportunity to meet face to face?

    Thanks so much.
     
  9. mrrxtech

    mrrxtech Member

    I'll let the Pros answer your question, but something to consider, since the lake probably has a granite bottom and is a huge heat sink.

    If the law allows in your area, I would think converting to a once through water side supply, drawing from the bottom of the lake with filtering at the supply pipe suction and Geothermal Unit, would provide water closer to the earth's temperature giving you more BTUs to draw from when heating.

    I've experienced how a closed loop supplied Unit vs a once through water source operate the winter. The once through water source is much more efficient, but has heat exchanger fouling/dirt/corrosion issues the closed loop doesn't have.

    I would think the money savings would more than pay for a water coil replacement, a new car, a college fund and several replacement units over the years.

    What do the Pros here think about closed loop vs open loop water source?
     
  10. Andrew Kulin

    Andrew Kulin Member

    Received my bill for February and it is the highest so far, just under 2,500 kWh for $540. On average, my electrical rate is just under $0.22/kWh with rates in Ontario scheduled to increase by a further 29% in the next 5 years. I have attached plots of hourly usage for the home and hourly outside temperatures from a nearby weather station. We have been at the place for a total of about 11 days over our 1st 3 months of ownership (green arrows). Otherwise the place is not in use, and everything that can be powered off is powered off.

    We had the HVAC tech out last week and he did some measurements. Found line pressure was low (about 10 psi incoming) and topped it up so that pressure was about 30 psi. Loop piping is 1.25-inch diameter, using methanol.

    He took the following measurements after topping up the line pressure:

    Incoming Pressure = 30 psi
    Outgoing Pressure = 20 psi
    Delta P = 10 psi

    EWT = 38.5F
    LWT = 33.1F
    Delta T = 5.4F

    EAT = 74.6F
    LAT = 94.5F
    Delta T = 19.9F

    Electrical:
    Furnace Compressor Circuit:
    - not running = 3.08A (678W) - ????
    - 1st stage = 14.4A (3,384W)
    - 2nd stage = 27.2A to 27.9A (5,984W to 6,138W)

    Furnace Elements, Fan, Transformers Circuit:
    - fan on (I don't recall what stage this was at) = 3.65A (803W)
    - fan off = 0.75A to 0.80A (165W to 176W)- he said that is because there are things like transformers, circuitry inside the unit that are always drawing power (???)

    He did not seem to think these measurements were out of whack.

    There is also a short stretch where the incoming/outgoing loop lines are exposed at ground surface along our shoreline. In an area that has a steep slope (30 degrees by eye) and looked to be too far for a backhoe to have safely reached to excavate. Could also have been due to shallow bedrock. I will look at this over the summer, check with a shovel if rock is shallow and if not try to hand dig and bury the lines a foot or two, plus build an enclosure with rigid foam insulation. Can't add fill to the natural shoreline and the slope is too steep that any material added obver the exposed lines will just erode off anyway.

    Lastly we had an energy audit done last week. The blower test indicated 2.2 air changes per hour and FLIR identified some cold areas on ceilings as well as a few points of air leakage here and there which are in the process of being addressed (next week with roofing work and additional attic insulation being applied).

    The important question to me, that I have not yet received any opinion or answer about, is does our electrical usage, with this furnace system, seem normal to you guys who sell, install, service these things? Is this what you would tell a client they should be expecting for a fairly new home of about 3,500 sq.ft. of heated space?

    If this is what should be expected then I can stop fretting over this and maybe look into converting the property from geothermal to propane heating.

    Thanks,

    bills.JPG plot01.JPG plot02.JPG plot03.JPG plot04.JPG
     
  11. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    Your Premier unit is single stage. At least I don't know of a two stage premier unit.

    So your second stage reading, the one with the big amp draw, is with electric heat on.
     
  12. mrrxtech

    mrrxtech Member

    Andrew,
    Check you performance using the Waterfurnace manual for you unit:

    http://www.waterfurnace.com/literature/premier/IM1555.pdf Page 37 and 38 have performance tables. You can also check you fan set up by comparing the "dip switch" settings to the tables in the manual.
    I believe your unit air temperature difference should be closer to 27 degrees, rather than less than 20 degrees.

    On my exposed lines at the house where the loop comes out of the ground and up to the Band Joist of the house, I used a selastic foam insulation that wraps around the pipe and has a glue joint along its length that seals the foam by removing a cellophane glue protector. This would insulate your pipe at the shoreline without building an enclosure.

    If you don't have ceiling fans, and you have a Cathedral Ceiling, the heat will be up on the 2nd floor. I notice this when heating and I go to the 2nd floor, it can get hot up there while the 1st floor is cool. I use a ceiling fan on high speed to equalize room temperatures. I have a long pole with a metal hook that I use to change fan speeds from the first floor. I don't like using remote controls which are available for ceiling fans.

    From what earthbouy said about the 2nd stage being electric heat, you would want to avoid changing the thermostat temperature to the point where the electric heat turns on. Determine the number of degrees above current house temperature that turns on the electric heat, and avoid that delta temperature by moving the thermostat up slowly.

    Another strategy would be to determine if the electric heat has it's own breaker and open it. Use the geothermal unit to bring the house temperature up to a the temperature you want then close the electric heat breaker for back up in case the unit can't keep up when it gets too cold outside. If the thermostat turns off the geothermal unit when the electric back up turns on, then this won't work. I'm sure the thermostat has an option to run both the geothermal and electric heat together if you read the thermostat manual and make wiring changes.
     
  13. Andrew Kulin

    Andrew Kulin Member

    I have put my concerns about the geothermal on hold for the past couple of months or so as we had a basement flood at the end of March and so we have been a little bit preoccupied with other issues. In the interim, I caved in to the demands of the kids and signed up for internet at the cottage and so with that in place, I recently replaced the original water furnace thermostat with an Ecobee 3 in late May. We have essentially not needed to heat the place for the last month or so but I had to go up to the place Tuesday night to be at the cottage on Wednesday as a contractor was beginning work on putting in some interior weepers and a second sump pump to reduce risk of repeat flood event. Weather up there Tuesday and Wednesday was unseasonably cool so I set the thermostat for 20C heat (68F). I have attached graphical output from the Ecobee web-site for the operation of the system while I had the heat turned on.

    The internal cottage temperature was 17C when I first raised the temperature setting to 20C so I was not surprised to see Aux. Heat kick in on the initial heating cycle. What I found disconcerting however was that under Stage 1 and Stage 2 heating modes, over 9 heating cycles with one exception, the geothermal heating at best kept the temperature stable or declined slightly but did not initiate a rise in temperature. Aux. Heat was therefore needed to maintain temperature at around 20C throughout the evening and night! I am at a loss to understand this. My take on this is I have an electric furnace with no geothermal benefit.

    Help?

    Andrew
     

    Attached Files:

  14. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    At first look it seems that the ecobee is turning the aux heat on when it should not. It seems that it is set up like an air source heat pump or a duel fuel system, which turns off the heat pump when aux heat engages. It appears after a certain run time (Y1 and Y2) times are always similar it engages aux heat and turns off the Y1/Y2 signal.
    Seems like a simple setup problem.
     
  15. mrrxtech

    mrrxtech Member

    Andrew,
    You're right, the geothermal unit isn't carrying the load.

    I'll take a look back at your posts later and let you know what I think.

    You either have a loop problem or a Freon side problem.
     
  16. mrrxtech

    mrrxtech Member

    Andrew,
    Using the Tables on Page 37 of your Unit manual, the 10 psi differential pressure across your loop water supply, the Technician measured with a 38 degree water temperature, is slightly higher than 16 gpm shown as a 9.3 d/p on the table. You can add another 1 gpm for the additional 0.7 pisd that indicates you have roughly 17 gpm of water flowing through the loop.

    With 3 gpm of water flow per ton required on the table on page 37, you would need 18 gpm, so your flow is only 1 gpm low at 17 gpm.

    The heat rise across your Unit should be 20 to 35 degrees for your Unit so I would expect a 30 degree heat increase at a minimum (with a 17 gpm flow) from Entering Air Temp to Exiting Air Temp. You show 20 degrees.

    In my opinion your unit is not operating per specifications with close to normal water flow in the loop. Before moving on to another heat source, have a Technician take a look at your Freon side performance/pressures and weigh the Freon if the pressures are low. You may have heard that the Freon can be removed, weighed and another charge of the correct weight can be put back into the unit to correct an undercharge of Freon.
     
  17. mrrxtech

    mrrxtech Member

    Mark,
    I found a Brass T in the Water Furnace manual below that can be used as the Outlet side of the desuperheater connection to the water heater drain valve connection. See page 12. The Inlet side of the desuperheater is piped from a T inserted into the cold water supply line to the water heater.

     
  18. Andrew Kulin

    Andrew Kulin Member

    We are at cottage now. I turned on system to get some heat (around 11:00 PM) as it is cool again up here and to check air temperature differentials. Nothing happened. So went to bed. Heard unit come on at around 12:30 Am. Went down to the basement and did the monitoring. Air temp differntials were between 23 and 23.5 F.

    Checked the Ecobee on-line monitoring this morning. It indicated that Stage 1 and 2 geothermal had been running to around 12:30, then Aux heat kicked in. There was no indications whatsover that the geothermal had been running at teh furnace (pumps not ciculating, no fan on, etc.).

    Therefore I am concluding that there is either an issue with the way the Ecobee is set up (I will be calling their Tech Line), or worse, the furnace was damaged during the flood.

    This probably explains the data shown in the graph yesterday.
     
  19. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    I might be wired incorrectly. When the thermostat gives a Y1 and later a Y2 signal (compressor stage 1 and 2) no heat is going into your space according to your log. Only when Aux signal comes on. Ecobee log only shows what signal goes out to the heat pump, not what is actually turned on at the heat pump.
    So if the heat pump compressor turned on 1.5 hours (12:30 am) when aux turned on, that would indicate an incorrect wiring.
    Make sure that the delta T you measure on the air side is not due to the electric aux running.
     
  20. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Your comments here are getting silly and display how little you understand about geothermal heat pump systems.

    The delta T on the air side on any geothermal heat pump is independent of source flow. It depends on unit capacity and air side airflow, both which have nothing to do with source side flow.
    The heat extraction is 44,523 BTU (17 gpm x 5.4 delta T x 485) which is right on target for a 6 ton unit at 38F EWT.

    In other words the refrigerant circuit is operating correctly, and no gauges should be attached since the performance is right on target.


    The Ecobee log clearly shows no heat going into the space with a Y1 (first stage) or Y2 (second stage) signal but with a aux signal, indicating either a mis-wire of the thermostat, or a heat pump lockout.
     

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