Just imagine a career where dealing with a problem like this is common. That's what you are actually paying for when you take your car to a pro to have it repaired. Your NOT just paying for a thermostat (Which while the most common part guessed is not likely to actually be the problem). Your not paying for a radiator, (Remotely possible, but unless the cooling system has been grossly neglected, not likely either). Your not just paying for a water pump and coolant. (There are reasons that this could be the right direction, but undiagnosed accurately should not have parts just thrown at it). My routine for similar reports of trouble is to first ensure that the coolant is full. That may mean removing a heater hose or some other component high on the engine to allow any air collected to get out, or maybe even be forced out with my pressure tester. Then I road test the vehicle with a scan tool connected. That way I can monitor the engine temperature with not only the gage, but with the sending unit that the PCM uses to control the fuel injection. If they both agree and the engine is running hot, then that directs my next step. If there is a discrepancy between the two temperature readings I need to find out why. If both sensors are reporting higher than normal temperatures, I watch to see how much engine load plays a role in both the creation of engine heat, as well as dissipation of the heat once created. I will often stop alongside the road and use my infrared thermometer to measure radiator surface temperatures. This shows me if the coolant in the radiator is flowing smoothly, or if there are restrictions. The temperature of the air going through the radiator also shows me if I might be dealing with restricted airflow. Engine surface temperatures, are also checked to see if the entire engine is evenly heated. Internal restrictions to coolant flow inside an engine can occur. Did you know that leaving a thermostat out completely can in fact leave the temperature gage low, while a portion of an engine badly overheats? I can't tell you how many times I have had to throw away a piece of cardboard that someone stuck between the radiator and the condensor so that they got heat in the winter, and then they forgot to remove it themselves come summer. Of course the reason they do that is the normal failure often associated with a bad thermostat, stuck open, FWIW, they can stick closed, or partially open but it's rare, like one out of fifty. People in a town like Erie Pa. that have a lot of cottonwood poplar trees have to watch for that cotton building up in the condensor cores, which results in limited airflow, and a similar report of overheating. Camaro's, and Firebirds of the 80's and 90's often had plastic ductwork come loose behind the bumper that was supposed to direct air through the radiator. At highway speeds, this would allow the ductwork to deform, and actually block airflow instead of forcing it through the radiator. Even the air dam below the radiator support is an important and often overlooked as a cause of engine overheating on the highway. The most likely cause of your vehicles problem right now is a coolant leak, and you probably have air stuck behind the thermostat. Replacing the stat, people opften then fill the system correctly, and the falsely think they fixed the car, only to have it act up in a week or two (or less). If you really think you cannot afford a pro to fix this, just wait till you blow a head gasket from actually overheating this a few times. If this is the Single Overhead Cam V-6 with two timing chains like mine, the special tool kit that ONLY WORKS ON THAT ENGINE, to set the timing chains is $500. You will find that only the top shops, and dealerships have invested in owning that tool kit. That's what your actually paying for.

And another nut bar hit's this site. You have been given most perfect advice from some of the best boys on this site. Why don't you listen ? 104F is the safest temporary temperature rize for the human body not to excede a 15 minuet time frame. After you alter the thermostat canceling your U.L. approval your tub now become not legal and insurance companies love that. How are you going to alter the high limit after you screw with the stat ? Most of those tubs come with timers. Is that going to be altered ? Do you have any idea how poisonous chlorine gets after it is heated behond safe levels ? And what is that safe level ? Do you have any idea how stupid it is to shut off the pump with over heated water ? I guess not. The water now does not move. You are now in a poaching tub. Sorry, i take that. I know you will leave the tub when you get too hot, but let's say your not feeling well. Had a bad day. Under medication or not up to snuff. Fall asleep, Wake up dead. Then what ? It could happen. I was a power engineer at a holiday inn for years and have pulled many unconscious people from the wet sauna ( and we locked it off at 104F. with an outside manual timer maxed out at 15 minuets. We took the water away because they were flooding the heating elements and shorting them out so they went to the pool and poured chlorinated water from empty beer cans onto the heaters. Chlorine poisoning and burned lungs. Nice vacation. I guess you have already made up your mind and we will not turn you. Good luck and be carefull. Maybe warmer clothing when riding your bike ?

I don't have equipment to measure the pressure differences but I have done some qualitative tests to evaluate the velocity of air that comes through a known opening (small window) for H/M/L blower settings as well as the velocity of air exiting the blower exhaust. What I found is that the pressure difference between the kitchen/dinette/family room space is greatest on the LOW blower setting and less on HIGH and MED settings even though the volume of air exiting the house from the exhaust is H/M/L as you would expect. I attribute this to the lack of MUA on the LOW setting due to the closed MUA damper. The hood flow I am perfectly satisfied with although it bothers me that the low setting is lower than designed because of the lack of MUA. I believe replacing the airflow MUA switch with a simple current sensing switch will be a good solution. We live in the PNW with a fairly mild climate with low temperatures seldom below freezing and never below 0 degree F and our furnace does not seem to have any trouble keeping up with the colder MUA inflow so far (although we have not had many cold days yet). opaone: Our MUA damper is a Broan MD10TU with a motorized damper triggered by a remote flow sensor switch. Thanks for the input on interlocking the MUA with the blower - I had thought that would be a good idea for MUA performance but not considered the static buildup aspect. The 6" MUA damper originally installed with the furnace is interlocked with the blower so I guess I better research how that works. And thanks for the kitchen compliment.

Plotting a route to a particular destination is more efficient if you begin by knowing where you're starting from-- as well as where you'd like to go. To this end, getting "before" sound level measurements is just as important as getting "after" levels. You can purchase a decent sound meter for around $50. If you have an i-phone, you can download the NIOSH Sound Level Meter app for free. Sharing the sound level data for the existing system's operation with your home builder may be sufficient to motivate them to help bring it in line with what can reasonably be expected. If not, the data are still necessary to determine the amount of any improvement achieved. Sound levels in any room of your home are the product of multiple sources; the HVAC system is only one of them. It may not be possible, given the construction of your home and the ambient outdoor noise levels, to get to a 40 dB level. I suggest a more productive approach than threatening non-payment if 40 dB isn't achieved is to work collaboratively with a contractor--ideally your homebuilder on his dime . If it's another contractor, you may need to do so on a time-and-materials basis. Identify changes which have the potential to reduce sound levels. Implement them in a priority order beginning with those which have the best potential versus cost. Work your way down the list until you've achieved your objective or exhausted your resources or exhausted your spouse or your contractor.