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Do you maybe have a steam humidifier on the furnace? If it was wired incorrectly or was damaged it could be trying to heat water when the furnace is not running, or when no water was present in the boiler. How confident are you on the diagnosis of the electrical issues? I've heard of underground feeders upstream of the breaker panel becoming damaged and ...


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Do you happen to have any sort of ozone generator or electrostatic air filter in your heating/cooling system? Sometimes those can give off a burning odor, I believe. Usually it's not very strong, but you seem to have done a whole bunch of reasonable tests to identify the source already.


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You're going to have to go look in the air handler, to determine how the control wiring is connected. The thermostat is nothing but a fancy switch, so it doesn't tell you much about how the system is wired.


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First, thank you to everyone who responded to my post!! Your time and response is very much appreciated. Below is response to the responses we received. We rent and our landlord advised that for the first 7 years he lived here they never had a problem with this smell. Actually, the problem began 2 years after we moved in and has continued for 5 years. ...


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Usually A/C, heat, and fan run the blower at different speeds. It's possible that the speed the A/C uses is dead. Any easy test, is to swap the motor speed wires connected to HEAT and COOL on the board. Then see if the blower starts with the A/C. If it does, that means the speed used by A/C is dead. Depending on the system, you might have to replace the ...


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As it sounds like it's an electronically commutated motor (ECM). My advice is to grab the control board, blower, and transformer out of the furnace. Then connect everything up as it was in the furnace. You should then be able to use the R and G thermostat terminals, to turn the fan on and off. You will have to bypass any limit circuits on the board, but ...


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All things being equal, a shorter vent won't increase the risk of backdrafting unless your vent is designed to rely on the stack effect (e.g., those big black pipes that come out of pit toilets). Ed Beal is right to point out that being below the roof line is relevant but laypeople and contractors often overstate concerns about backdrafting. They do this for ...


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I suspect your water heater is gas and in a utility closet on the ground floor. Check in there to see if the smell is stronger or if a water pipe looks like it may be leaking a little. My thought is damp insulation inside the water heater shell could be producing this odor.


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I would only let the fan run constantly or on manual as you suggest if you have a variable speed fan in the unit that will change based on the call for heat/cool.


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This is the most common problem with the Nest. You need to hook up a "C" wire. Here's the thing. Originally, thermostats were passive devices - nothing more than switches. And so, controls were wired in a "switch loop" similar to how switches in houses were wired before current electrical code. Power went in a functional loop: from the 24V ...


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AAC block is known to have better thermal insulation than brick. Based on my unmeasured observations, a 220 mm brick wall is probably a better sound insulator than a 100 mm AAC block wall. Different materials will absorb/filter different frequencies (thermal energy or sound), so a combination of both brick and block should provide the most comprehensive ...


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Our unit was off level quite a bit which caused damage that first caused it to perform badly before it quit completely and had to be replaced prematurely. It was installed in 2000.


2

You may want to make a trip to the big box store and purchase a piece of high density foam insulation board. You should be able to find materials that are colored pink or blue that comes in 1" or 2" thicknesses. Carefully cut pieces that will fit between the window bottom, side wall and the inward protruding part of the AC unit. If cut correctly you should ...


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The key will be to a) block all air paths, and b) have rigid barriers rather than flexible barriers. So, those pleated plastic barriers must be supplemented, if not replaced. Ideally, you should remove the AC unit (don't drop it out the window!), remove the plastic barriers and frames, and then reinstall the AC unit with 1/2" or thicker plywood on either ...


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It works for sure,especially on metal roofs. When continiously sprinkling a metal roof the roof works like a heat exchanger. You are carrying heat away faster than it comes :)


3

Before you begin, make sure to pull out/turn off the serviceman switch, and/or turn off the breaker, to remove power to the unit. Once you open the unit, you'll want to discharge the capacitor(s). A charged capacitor can store enough energy to kill you, so you want to make sure you discharge them. Test the motor To check the motor, you're going to want to ...


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The electrician that says three separate is most accurate as far as code safety. The other two know it will work but all phases are tied into three ganged breakers. So, if there are separate breakers for each phase it only trips one phase the other two can remain off or unused.


1

There should already be a transformer on the unit. I believe it's on the back of the unit, mounted to a junction box. There should be two exposed terminals on the transformer. One is R, and the other is C. To determine which is which, use a volt/multimeter to measure AC volts between the R wire going to the thermostat and the transformer terminals. One ...


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HVAC Technicians must understand how to take proper measurements for Delta T and ambient temperatures along with the Wet Bulb temperatures. With a little math You really do not have a reason to crack into the refrigerant system. The industry in my area as a whole is quite vocal about moving away from the gauge on every PM approach. It is just time for ...


3

A cheap option, is hanger strap. It's available in both metal and plastic, and in various sizes.


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I like PVC strap tape. You can hang it about anywhere with about anything. It doesn't kink up like metal, and it isn't sharp.


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If you don't care how it looks, just put some screw eyes in the wall above where you want the duct work to be, and loop some wire around the duct work and attach both ends to the screw eye. Quick and easy. As an aside comment, if there is a significant difference in temperatures between the air going through the duct work and the air outside, you may ...


1

I had a furnace guy come in the morning. He saw the furnace and said "Oh my god!" After two hours he decided he couldn't figure it out and they sent another guy later that day. They finally figured it out. Since a guy who works with furnaces for a living couldn't figure it out after two hours I think I never had a chance to begin with. So in the end, the ...


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If you've ever assembled a PC or have any DC electronics knowledge, the AC can make things confusing. It's educational to pretend that the transformer is a 24 volt DC supply, and that R/RC/RH is +24V, and C is GND. (not to be confused with the "equipment grounding conductor" - the bare/green wire in 120V wiring.) +24V "power" goes to the thermostat. GND ...


2

I'll use this gif from my other answer, to try and describe how the system works. I'll focus only on the heating side, just to keep things simple. When the thermostat is not calling for heat, the circuit is open and electricity cannot flow. Once the temperature in the room drops below the set point, the switch in the thermostat closes. When the switch is ...


2

You probably can't do it yourself, but an HVAC technician likely could. Moving the unit likely requires: Evacuating the refrigerant Reconfigure (and potentially rerun) the line sets. Reconfigure (and potentially rerun) electrical. Physically moving the unit. Charging the system back up with refrigerant. You could probably do number 4, and maybe number 2 ...


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According to Trane installation instructions, the technician is correct. They do require 3' of clear space in front of the control box. As for why the technician chose this orientation, I can only speculate. It looks to me like the access panel is on the corner of the unit, which would mean there has to be 3' clear space at the corner. Obviously the ...


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These units are designed to be outside, so there's no reason to cover it. If you're really concerned about it, go ahead and cover it. Just make sure you don't restrict the airflow, as that can impact how well the unit works. The manufacture likely recommends annual cleaning, and maintenance. Which will probably do more good for the unit than the cover.


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Yeah, you can buy covers, and check this one out, too... perfect for urban duck hunting


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The + is yellow, and the- is blue in your case (technically common, or C). The dog could have blown the fuse. There is a 3amp fuse on the furnace control board that protects the low voltage side. If you don't get anything to come one, check that fuse.


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Your dealing with low voltage AC so you don't have to be concerned with getting the + and - backwards. Assuming the yellow and blue wires connect to the coil on the contactor, you can safely connect the two wires from the house to the two wires in the outdoor unit. Prior to doing any work with the wires, verify you have 1) the power off to the furnace/air ...


3

Wire colors with HVAC wiring are non-standardized, so the colors themselves don't help much. Your furance/air handler should have a control board with terminals labelled R, W, Y, G and C. There should be an existing wire that connects to all of these (though maybe not C) that goes to your thermostat. If anything is different in your setup, please update ...


2

I did this, almost exactly as you have drawn (in my mothers home when I was a teenager). You will need to support the back end if you cannot support the bottom "lip" of the AC from sliding forward. In other words, the AC will have torquing-force. The reason I used a shelf for my AC was because I couldn't support the top. But since you are putting the AC ...


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Modifications to the flue are likely to be unwise and may be counterproductive or cause your heater to be dangerous or fail any safety checks. There are fairly strict back pressure requirements for proper function. Even some models from 20 years ago recaptured some of the waste heat into the incoming air (concentric balanced flue).


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It is generally not worth the time and money to try to capture the lost heat through the exhaust system of the vast majority of tankless/on-demand water heaters. The heaters are now so efficient that they can vent the exhaust through plastic (PVC) pipe. Since these heaters also only operate when there is a call for hot water, they do not run very often. ...



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