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14

There are two very different issues here: Power to the Thermostat I flipped off all the circuits in the fuse box, and the thermostat on the first floor powered off. However, the thermostat on the second floor still had power. A thermostat is typically powered primarily by a transformer. However, many thermostats include battery backup. There are a ...


6

Thermostats get power from a low-voltage transformer that is either inside your air handler or very close to it. That same transformer also powers the circuit boards and controls of the air handler. That transformer, along with every other electrical device in the house will be connected to a breaker. If you turned off all the breakers and one thermostat ...


5

This is probably a matter of not knowing where your service panels are. Plural! Find the meter and follow You need to "follow it from the meter" as it were. Find the meter; easy. Then you'll have one of three things: Additional compartments in the meter cabinet that open up (do not break any seals). Very obvious conduit to another equipment box ...


3

You could get some flexible HVAC duct and install it up there. It's only for one register so it shouldn't affect the cooling or heating.


3

Drain pipes have P-traps in them that hold water to seal the drain from sewer gasses that would otherwise waft up out of the drain. Check your drains (sink and floor) to see if they have water in the traps. (the smell is probably being moved around by the fan in the heater)


2

Remove the silicone pieces and trim the grey rubber back and then use Great Stuff to fill in the voids and insulate the pipes. You've got a pretty good opening there and you don't want any critters crawling in there.


2

My advice is to gently pull straight out. I did it but I was not sure due to the difficulty of the release. Secondly, I would not ever buy an AC system that would only work with a special Thermostat! A replacement for my Infinity by Carrier is $960.00 (not customer friendly). The only reason my Thermostat is a problem is that the AC button broke. Otherwise ...


2

Thanks guys, I had a pro check it out. The furnace is working fine. He found too much air restriction on the return side, and corrected it. There was too much of a temperature difference between the cold return and the hot side. The heat exchanger was fine.


1

The most common way that two thermostats work with one HVAC system is through the use of a zone controller like one of these. They can be installed near the air handler, but it could also be in a nearby closet so it can be monitored or adjusted without going in the attic. The zone controller makes all the decisions about controlling dampers and calling for ...


1

To troubleshoot this, you can remove the Nest and use a jumper wire to touch the red and green wires together. The fan should come on. If the fan does not come on, then the system is not wired correctly on the other end. You'll have to take a look at the air handler side of the wires to see what happens to the green wire. If the wire was broken or if ...


1

It's unlikely that going from a larger pipe to a smaller pipe (which is essentially what the flex hose is) would cause that. However, the repair man may have meant that the flex hose was undersized for the gas line inside the furnace, which would make more sense. Expanding flow could certainly cause the noise, but to really figure out what's causing it you'...


1

The transformer(s) that power hvac systems have a primary winding that is 120v in most U.S. cases (some are 240). These are controlled from the service panel or a sub panel. The secondary side of the transformer is normally 24vac I have seen 6v to 32v systems all considered low voltage on the secondary the transformer primary is powered in most systems If ...


1

I agree with ThreePhaseEel, no. If the unit is not in use, then there should be no reason to preventively treat the condensate drain-line. However, you may benefit from adding water alone to the condensate drain-line monthly, if it's connected directly into the building's sewage system. If the condensate dumps outside or into a sump-pit or sink, then not ...


1

I would possibly use 1 layer of tape sticky side out then coat with silicone to fully seal. You really won’t have any real efficiency losses but that opening is large enough for rodents to enter, so I would want to seal it up for that reason. I cases where I don’t want the tape to stick to things I will put it on sticky side out and over lap it on itself, ...


1

The catch about these new units is that they are sometimes condensing units. I had two installed. One has a direct feed to the drain, while the other has a pump that pipes it to the same place. We had a super-hard freeze (uncommon where I live) and the pump line froze up. That, in turn, tripped the failsafe switch, which cut power to the unit (required by ...


1

Another consideration is installing the unit on vibration isolators. When the fan turns on, it will cause the unit to move (slightly). Likewise, when it’s running, the fan will cause some vibration in the unit. Make sure the unit is isolated from the framing. I prefer hanging the unit from the roof rafters rather than sitting it on the ceiling framing. ...


1

Since you have some space in your attic, and you seem set on installing the furnace up there, I think it would be easy enough to make a small room just for the furnace. I did that in our new addition, as the dedicated furnace for the addition was an afterthought after running ductwork over from the original furnace location turned out to be impractical. We ...


1

Yes you can put a high efficiency furnace in an attic hose if allowed by your local code. I use self regulating heat tape if there is any chance of the condensate line freezing. Have you considered a mini split system? I have installed high efficiency furnaces in attics in the past but you would still need a separate compressor unit outside for AC. The ...


1

You might try a register end boot. But your tap into the rectangular duct may need to be closer to the end to get the rise to miss the TJI.


1

Sounds a lot like my son's new house. Since you already have an HVAC duct that runs through the crawl space just add a register to that duct. My guess is that unless you're actually going to seal the crawl space and make it air tight relative to the rest of the basement, you'll have enough leakage around the access door so that no additional return is ...


1

You already have a C wire, it's just not called by that name From a close examination of your furnace's wiring diagram, the fat brown wire it supplies in the thermostat wiring compartment is the C-wire feed from the transformer. The way your system is wired connects the brown wire in the outdoor-unit cable and the brown wire in the thermostat cable to that ...


1

Go for it Any modern furnace will have enough capacity on the C wire to support a "smart" thermostat as well as powering the control board and the compressor contactor, so I would simply take the coiled-up blue wire ends at the splice, nut them together, install your new thermostat, and enjoy!


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