New Installation in Maryland

Discussion in 'Geothermal Heat Pump Testimonials' started by WhiteRabbit, Dec 11, 2010.

  1. WhiteRabbit

    WhiteRabbit New Member

    Posted by Geome

    OK, I now realize that:
    1. Long run times in Stage 1 are more efficient.
    2. Scroll compressors are designed for long runs.
    3. Setting my Honeywell TH8320U1008 to #1 Less agressive temp control in heat mode [Item # 0680 in the installer setup] should allow the system to actually reach its set temp and cycle off.

    It would seem that I have achieved my goal, however the system cycles back on within 10 minutes and runs for another several hours then repeats. The set temp and actual temp never change from 71 degrees on the screen, but the manual says that it changes internally up and down by + or - 2 degrees. I just can't believe my house looses 2 degrees of heat in 10 minutes. This afternoon I manually shut the heat off, and the house held 71 degrees for over two hours before the thermostat suddenly dropped to 69 degrees. I then turned the heat back on and it only took about 30 minutes in stage 1 to get back up to 71 degrees. The system then continued to run in stage 1 for another 2 hours before automatically shutting down for 10 more minutes.

    The other suggestion was to set the Cycles per hour [Items 0220 and 0230 in the installer setup] both to 2 rather than 3 which is the default. I have not done this yet, but would it also affect the time that the unit is OFF? If so, I will change it tomorrow and see if it allows the system to remain idle longer and still maintain my temps.

    Again, thanks for all of the input. I never thought that a home heating system would be so intricate to manage.

    White Rabbit
  2. Palace GeoThermal

    Palace GeoThermal Well-Known Member Industry Professional Forum Leader

    If you set the CPH to 2 and your heat pump runs twice in the first 20 minutes of the hour, then the heat pump will not come back on until an hour has passed.

    This is not a bad thing unless your house temp drops to the point that you are feeling cold before the hour has passed.

    Hope this helps.
  3. zach

    zach Member Forum Leader

    vision pro

    SInce we are on the topic, may I ask, what are some of the advantages of this thermostat?

    I have a pretty simple White Rodgers which is doing the job fine.

  4. WhiteRabbit

    WhiteRabbit New Member

    Darn if I know Zach.

    I have had a simple mercury on off switch thermostat for 33 years. Having said that, these digital setback thermometers allow much more flexibility and control, therefore they require numerous setting adjustments leading to complexity for the average user. :rolleyes:
  5. geome

    geome Member Forum Leader

    The house may not be loosing 2 degrees in 10 minutes. The +/-2f is the point at which the Displayed indoor temperature will change from the set point temperature. This is not necessarily the point at which the thermostat will engage the equipment.

    CPH can effect off time, but not necessarily. For example, near the system outdoor design temperature, the equipment may run continuously (to try to maintain the thermostat set point) regardless of the CPH setting. So, there would be no off time in this case until the thermostat is satisfied.

    The CPH setting controls the Maximum equipment cycles per hour. It doesn't force the equipment to run the number of CPH that is set. Reducing CPH will reduce the Maximum number of cycles per hour, but at the expense of a larger temperature swing, (which may or may not be reflected on the display of the thermostat per the above explanation.) Go by your comfort, not the displayed temperature.

    From personal experience I know this is difficult to do. You can try placing a digital thermometer very close to the thermostat to see what is happening with the indoor temperature in the real world as opposed to the Honeywell world. :D I did this with a digital meat thermometer balanced on the thermostat until I figured all of this out. It was a pain since it kept shutting off. Perhaps another (temporary) job for the TopFin (thanks for that suggestion BTW.)
  6. zach

    zach Member Forum Leader

    Yes, thanks again for the Top Fin tip. A nice device until I can buy a WEL server.

    Wondering if there is some employee at Petsmart in logistics wondering why all of a sudden the run on digital thermometers?

    Happy Holidays everyone
    Last edited: Dec 21, 2010
  7. WhiteRabbit

    WhiteRabbit New Member


    I do have a bulb thermometer right next to my digital on the wall and it says the "air" temp (where I have my thermostat) is 72 degrees. The rooms in the rest of the house show about 68 degrees on digital room thermometers but I have found that they are low by 2 degrees, so I believe the rest of my house is actually about 70. This is comfortable.

    I am leaving every thing alone right now with the CPH set at 3 rather than reducing them to 2.

    NOTE: Before I found the PetSmart digital thermometers, I ordered four similar units on EBay which are "Only in Centigrade". They have not arrived yet but, if any of you in Canada want these, just PM me and I will send them to you for the price of postage.

    Thanks again for everyone's continued interest.

    White Rabbit
    Salisbury, MD, USA
  8. geome

    geome Member Forum Leader

    Jimmy Carter may like them. :D

    Have a good Holiday too!
  9. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Thank you for the Forum wide Christmas card!:)
  10. geome

    geome Member Forum Leader

    One house appears to have engaged an auxiliary heat source in addition to their geothermal system.
  11. WhiteRabbit

    WhiteRabbit New Member

    I used a wood stove for 15 years along with passive solar heat. I gave up on burning wood about 8 years ago, just too much work. As you can see below the chimney is stll in place, but closed up inside.

    Today is a great day for passive solar. My solar room which faces directly South is 85 degrees and my geo system has been off for several hours. Outside temps are in the mid 30s with no wind. The white sections you can see on the windows are solar curtains which absorb heat during sunny days and block cold at night. The inside floor is brick, now covered with commercial grade carpet, but it still absorbs a lot of heat during sunny days and radiates it back at night. I have contemplated solar roof panels in the past because the house faces South, but the costs and efficiencies did not add up for me.

    White Rabbit
    Salisbury, MD
  12. geome

    geome Member Forum Leader

    With Honeywells, I just remembered 2 additional CPH items that I didn't mention previously.

    1) Making a manual change to the thermostat will engage the equipment, even if the CPH is reached for the given hour (otherwise people would think the system is not working and call for service, rip the thermostat from the wall, etc.)

    2) I recall reading that going into the installer setup resets the CPH counter too.

    If the weather guessers are right, we're looking at a white Christmas here in SW VA.
  13. WhiteRabbit

    WhiteRabbit New Member

    Fellow Canadians, or those who use Centigrade, I have received my digital thermometers over the holiday, but have no use for the centigrade type. :cool:

    [​IMG]I have four of these which you can have for the price of postage which should be less than $5.00 to Canada. Just PM me with your address and I will send them off. They are brand new, never used and are great for checking you water temps EWT and LWT as well as air temps in and out of your unit.

    White Rabbit
    Salisbury MD
  14. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    I'll bite

    I could immediately put these to use. So I'll enter the lottery:).

    Shine Energy Systems Inc.
    1204 Nicola Street
    Kamloops, B.C.
    V2C 2S5

    I'll make sure they go to a good geo home (ours).

    Can send bacon and/or beer in return.
  15. geome

    geome Member Forum Leader

    I'd hold out for a tuque. :D
  16. WhiteRabbit

    WhiteRabbit New Member

    And the Winner is:

    Chris Koch of Kamloops, BC, Canada. :D

    I am going to the Post Office some time today and send the thermometers off to you.

    Hope they are usefull.

    White Rabbit
    W. Deckert
    Salisbury, MD, USA
  17. griffin 6

    griffin 6 New Member

    did you get that running all the time thing resolved.
  18. geome

    geome Member Forum Leader

    Only 32f - 122f? :(
  19. engineer

    engineer Well-Known Member Industry Professional Forum Leader

    32-122F? perhaps not true!

    That pic looks like the very same Top Fin I bought two of on Christmas Eve. I saw the 32-122 range limit and was a tad disappointed, initially.

    In use mine tops out at 70C / 158F or thereabouts, switching to an error mode above that. It passed the ice bath test at 31.5F - more accurate than my Cooper DFP450 which reads 33.5 on the rocks.

    I haven't found Top Fin's bottom range - I stuck the probe into the cold air discharge of the kitchen freezer and it indicated -10F or so.

    I had one with me on a family trip to south Florida and my daughter ran a fever for a dutifully indicated 102.5, which is about what my well-calibrated parental hand-on-forehead "indicated"
  20. geome

    geome Member Forum Leader

    That would be great if the range is wider than the specs listed on the web site. I have seen other thermostats with a range of -58f to 158f. Maybe the guts are shared...

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