The IAQ is a communicating thermostat. The thermostat sends and receives serial data over a three wire interface. It can communicate with many different devices, one of which is the Equipment Interface Module (EIM). At a minimum, you need an EIM. There are other optional devices that may be of interest, including an outdoor temperature sensor. The EIM is located wherever the air handler is located. You will hear the EIM relays click if you are next to the air handler, but you will not hear them in your living room. The thermostat itself is silent.

I had a new pool company close my pool last year and open it this spring, and have had nothing but trouble. The final straw is that my filter pump no longer kicks up to high speed in auto mode. This was never a problem before. In service mode, the 2-speed function works fine, but in auto, the heater, cleaner deck jets and spa circuits no longer trigger high speed. I have checked the programming and see all 4 circuits listed under the 2-speed function. I have looked at the wiring and it appears to be in order, other than the fact that the outside terminals of the 2-speed relay are not wired to the inside terminals as shown on the panel. The upper inside terminals appear to connect to the correct terminal on the pump relay. The lower inside terminals are color coded and appear to run to the pump (see below). The low voltage wire correctly connects to the proper terminal on the personality board. I did have my pump rebuilt this winter so there could be a change to the wiring at the pump. However it seems to me that if the high and low speed wires were incorrectly connected at the pump, I wouldn't be able to switch between high and low in service mode. Likewise, I assume that if there were a wiring fault between the load center and the personality board, I would not be able to switch to high speed in service mode from the personality board. Therefore, I conclude that it must be a programming problem, but I can't seem to track it down. Also, I am using a whisperflo pump, so all intelliflo circuits are set to "none." Any thoughts or suggestions? Thanks in advance.

Thanks Scott. The simple fix is just to swap the heater wires with the pump wires on the relay so that the pump is directly connected and the heater is under relay control. But I can move them both off the relay. It's not that hard. The 4 wire control cable is there but I'm thinking the pump speed has been working in manual mode for the last year and a half and not being controlled by the easytouch. See photo below (I go a bit overboard with these photos but it helps me when others provide them in their posts so maybe it will help others in the future). The 240V lines from the breaker are the 2 lighter blue wires. The red wires got to the heater direct from the 240V line (pre-relay). The yellow wires go to the IntelliPro pump (post relay but not for long). The blue and brown wires go to the EMI filter for the Intelchlor transformer (post relay).

Just my two cents, on heat transfer in a dynamic environment. I.e. fluid as opposed to a solid block of anything. There is a lot of opposing theory here. First lets try and apples and apples it. If the surface area and thermal dynamic properties of the heat exchanger are the same i.e. one is aluminum a one is copper. And the only variable is the speed at which the water flows through the pipe. You first have to understand the effects of laminar flow on the xsfer of heat (energy) from the walls of the heat exchanger to the fluid in the center of the pipe. Due to the increase of friction at the edges of the water Colum inside the pipe , the water in the center of the pipe flows faster, with me so far? The statement "heat xsfer is greatest when the deference between the bodies is greatest" is in a way correct when you look at percentage of transfer. What you fail to take into account is that the transfer works both ways. At the same time you are heating the water , you are cooling the pipe. Thus requiring more energy to heat the pipe. Since the energy to heat the pipe is limited i.e. the amperage of your wiring in a heat pump or flow of gas in a furnace, You must stick to real world. Another fact is heat transfer has momentum. Once you pass a point of the curve you see a ramping effect called thermal momentum. Soooo if the gauge is how fast you raise a body of water outside the exchanger i.e. a pool or spa the question is simple the longer a molecule is in proximity to a heat source the more energy it will adsorb. So the two options are 1. to run that "piece" of water quickly through the exchanger so it can deposit its heat into the body of water and go back and get more? Or , 2. to allow that "piece" of water more time in the exchanger to gather more energy to deposit it in to the water. The end result is the same, Hot. The deference is the curve. We use this formula every day in controlling chemical reactions through temperature. The slower moving fluid reaches the steeper part of the curve faster, thus gaining Thermal momentum fasterÂ.. ending up with the body of water reaching a desired temperature faster. DamÂ.. I need a beer!