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-   -   Changed dip switches but air handler blower still on high (https://www.askmehelpdesk.com/showthread.php?t=187217)

  • Feb 23, 2008, 03:18 AM
    marfidky
    Changed dip switches but air handler blower still on high
    We bought our house in December, 03; first electric bill was over $400! We now have a 3.5ton Trane heat pump (new in 1/04) and a 4 ton Tempstar Varible Speed (EBV4800A) air handler (new in 6/04); the house is a 2000 sq ft ranch. Air conditioner works fine but have not been satisfied with the heating for the past 3 winters - really high heating bills! We did change out the Hunter Programmable Thermostat for a Honeywell Programmable Thermostat, RTH 7500, this week, and the auxiliary heat is not coming on as it was.

    Yesterday we finally had the HVAC man change the dip switches to reduce the heat air flow, which has been on high speed since the unit was installed. He said he lowered the speed, but I could tell there was no change, so he went back and lowered it again, down a total of 600. He said, "it is down to 1400 now", and left. The air flow was still on high. After they left I read in the air handler installation book that "the system had to be turned off to adjust the dip switches or the changes would not take effect". The system had not been turned off. So I figured that if I turned the system off for awhile and then turned it back on, the change in the dip switches might take effect; that did not work. The air flow is still on high. Why aren't the dip switches responding to the changes? Thank you for your help!
  • Feb 23, 2008, 06:27 AM
    hvac1000
    ((Why aren't the dip switches responding to the changes? Thank you for your help!))

    They should respond if adjusted correctly but looks like the service person who was there did not know how to do it.

    Your best bet is to call the company and complain about the situation and have them send a different person to make corrections.

    BTW the lower blower speeds will not have much of a effect on your utility bill to start with so if you were thinking you will save big $$$ by lowering the speed you will not be happy with the results.

    You have 2000 SqFT to take care of and 1400 CFm is not too much for that area especially since it is a ranch style.
  • Feb 23, 2008, 08:23 AM
    acetc
    Just to add to the clarification, the more the aux. heat operates to maintain your desired room temperature the higher your electric bills. If you can maintain room temperature with only the heat pump as much as possible you can save on operating costs, this may be accomplished with the addition of an outdoor thermostat to keep the aux. heat from coming on until it gets to a point where the heat pump will no longer keep up with the interior heat demands, usually around 32 degrees.Heat pumps are slow to recover and should be left at the same temperature constantly without going into a night setback. Good luck, Mike
  • Feb 23, 2008, 09:04 AM
    marfidky
    To HVAC 1000: When the fan is blowing on high, the house actually cools down, then gradually the heat pump has to bring the temperature back up. In the literature it says the heat fan should be set at low to med: it is blowing on high now (either 1800 or 2000, I'm not sure) and that is just too strong. I want the velocity of the fan cut back, not because that would save on our heating bill, but it would make it easier for the heat pump to keep the house at the set temperature (which actually would save on the heating bill). When the HVAC man said it was set at 1400 he was mistaken, the changes he had just made to lower the fan speed did not take effect. Thank you for your help.
  • Feb 23, 2008, 10:38 PM
    T-Top
    Is your new thermostat set up for variable speed. The control board will realise if you have a call from Y(first stage heat) or W (seconde stage heat)with out a G call (blower). A service tech can reset the control board from just pulling the low voltage fuse on the control board for a few seconds.What do you set your thermostat temp at? The more you play with a heatpump thermostat (temp swing) the more it will cost you.
  • Feb 24, 2008, 01:01 AM
    marfidky
    To T-Top: The new thermostat does have the connections you refer to. We keep our day temperature at 69; night time temperature at 65. After the air handler installation in 6/04, nothing was ever done re: the air speed (it has taken me three winters to convince my husband that the air flow was too strong) until we called in a HVAC person in January. He found that the "dip switches" were all "OFF". He then set them according to our installation instructions. We could not tell any difference in the air flow after he set the switches. (He also left the "door" off the filter slot and I did not find it until I changed the filter almost three weeks later). So we decided that it might be best to get the actual installers back in here to get the air flow regulated; they were here Friday afternoon; they said they lowered the speed to 1400, but right now it actually feels like the air is blowing stronger! It is much more comfortable in a cold house than it is when the blower is on. The question I'm raising this time is: could the blower still blow the same when: the dip switches are all "OFF"; when they are set according to the instructions AND when the blower is set at 1400?? Thank you for your help!
  • Feb 24, 2008, 01:22 AM
    hvac1000
    Is this your first house with a heat pump?

    Heat pumps always blow cooler air to start with than a gas or oil furnace.

    I just mention this because many people think a heat pump will put out warm air that feels warm to the touch and that is just not so. Heat pumps deliver heat but at a much lower temperature than a fossil fuel furnace.

    This has caused much confusion with new home owners and first time heat pump users.

    What is you temperature of the discharge air at the closest register?

    What is the temperature of the air going into the return register?

    Make sure the heat pump is running for 5 minutes before taking sample temperatures.

    You have more of a temperature problem than a speed problem. This may also tell if the heat pump is working properly
  • Feb 24, 2008, 11:59 AM
    acetc
    It is possible on some furnaces to change the blower speed on air conditioning and a different speed on heating, the new furnaces have many variations of air flow. Good luck, Mike
  • Feb 24, 2008, 06:44 PM
    marfidky
    acetc: Yes, this one has that capability; the AC works fine on full speed; it is only the fan speed on heat that needs to be lowered. Thank you for your response.

    Hvac: No, this isn't our first home with a heat pump, and I do realize that the initial air is not warm air. As you suggested, I just checked the temperature coming out of the register: 80 degrees; temperature going into return register was 70. We have the thermostat set at 70 today; it is 33 degrees outside.
    A small amount of coolant was added to the heat pump in January. Previously it was checked in the winter of 2006. Coolant has been added twice, I believe, since the new heat pump was installed in 1/04. Thanks for your response.
  • Feb 24, 2008, 09:34 PM
    hvac1000
    ((Coolant has been added twice, I believe, since the new heat pump was installed in 1/04. Thanks for your response.))

    Coolant is known as refrigerant. If refrigerant has to be added to a system there is a leak. If there is a leak then it should be fixed or you will continue to have a problem.

    While I realise this is a different subject it would be very interesting to have a REAL professional service person who really knows heat pumps take a look at your units. The reason I say this is because a 10 degree differential is not much to talk about with a properly operating heat pump and this may be contributing to your utility usage usage.Also while the real professional is there they can look into the dip switch problem and test the controlling factors to bring that blower under control .

    If the service man cannot set the dip switches correctly or find out the problem then I would be real concerned if he or one of his associates added refrigerant to the system.

    One other small note. The pressures outside will change a bit when the speed of the indoor motor is changed. How could the company set the correct refrigerant charge in the outside unit with the inside unit operating at the highest speed since that is usually reserved for the air conditioner operation and in many cases high speed is not used at all.
  • Feb 25, 2008, 01:13 PM
    marfidky
    To: hvac1000
    When you say "a 10 degree differential is not much to talk about with a properly operating heat pump", are you saying that this "differential" is not good? Is the difference too much, or not enough? Yes, in "researching" this problem I find that the high speed is seldom used and then only for A/C. That's why I think it is important that the speed of the blower be lowered when heating! Thank you for responding.
  • Feb 25, 2008, 01:29 PM
    hvac1000
    Is the difference too much, or not enough

    Not enough in my opinion but that also depends upon the outside air temperature. You really need to have your system checked by a true professional. Playing with the dip switches will get you no where as you are finding out.

    Posting here with your type of problem can be a large guessing game because we do not have access to unit pressure readings, exact temp readings for both outside intake and discharge temps and also the inside unit for the same. A amprobe reading for unit draw and other information is all necessary to determine proper operation of your equipment.

    Something is not allowing your motor to reduce its speed. Playing with the dip switches have proven not to help the situation.

    Here are a few facts for you. All new homes have very cheap HVAC equipment for the most part and the installers and service men are not the brightest of the bunch unless you pay a bunch extra for a better unit, proper instillation and checkout.
    How do I know this? The builders are a cheap lot that usually use the lowest bidder and naturally the homeowner gets a shoddy job. These are just the facts and that is why I am telling you to have the system checked by a real professional and not the people who installed the unit to start with.

    There are many aspects to a properly operating heat pump system and the fan speed is just a minor one. If your bills are high in your opinion I would be getting that unit serviced by a true professional so you get all the energy savings possible.

    I have been around to many years and the story is always the same.
  • Feb 25, 2008, 02:12 PM
    marfidky
    hvac1000: When you say "a 10 degree differential is not much to talk about with a properly operating heat pump...", are you saying that 10 degrees is not satisfactory? Is 10 degrees difference too much, or is 10 degrees not enough difference? Thank you for responding.
  • Feb 25, 2008, 02:17 PM
    marfidky
    hvac1000: Sorry for the duplicate - your answer was not posted when I got online.
    Thank you so much for your help. This is what I believe we should have done all along. We live out in the country, 45 miles from a true professional; I have called and the fees are prohibitive, but it may be necessary to get this problem solved. I do appreciate your time.
  • Feb 26, 2008, 06:27 PM
    T-Top
    Your average supply temp should be in the mid to upper 90s. Something is wrong if you only get a 10 degree split.
  • Feb 26, 2008, 06:36 PM
    marfidky
    T-Top: Would the "supply temp in the upper 90's" hold true even when it is 30 - 35 degrees outside? Thanks for responding.

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