New answers tagged

1

Put a drop of super glue on the bare shaft, then slide the impeller fully into place. Put the nut on without gluing it. Leave it for an hour so the glue can set up. You could also use a threadlocker liquid on the shaft. I have repaired loose impellers for combustion air fans inhigh efficiency furnaces. I also use this repair for bath fans and rangehoods.


1

After speaking to a service tech, I've confirmed that the design of the Taco valves is that the boiler contact is not energized when in manual override. However, he also stated that he's seen cases where they failed with the contact energized, so I'm planning to disconnect that wire if I have a similar situation in the future.


0

That may vary by compressor. As such, the matter is decided by the labeling, instructions and data sheet for that particular compressor. If it connects to mains power, this is called out in NEC 110.3(B) and obviously, misapplication will void the warranty.


3

No, a typical fixed-use AC compressor will NOT work properly in any orientation but upright. Most designed have a sealed can containing the compressor itself with an electric motor driving a crankshaft to which a connecting rod is attached which drives the pump. The bottom of the can is filled with lubricating oil for the bearings on the shaft and ...


-1

That will also depend on the design of the compressor - on my car the compressor is the lowest point...


0

Add inlet area /with filter to the furnace. This permits more air to flow over the furnace tubes. The furnace will be putting out about the same amount of heat but it will have a larger amount of air so the air temperature will not be as high. And as commented , make certain all dampers are open ; there may be dampers in the ducts not just at the outlet ...


0

This isn't so hard after all Old bimetal thermostats used extra contacts on the mode select (heat/off/cool/e-heat) switch to determine whether O or B was energized, so as a result, your old thermostat provided both an O and a B terminal, in order to be compatible with all heat pump systems, as some require an O wire while others require a B wire. However, ...


3

This veers towards being "a matter of opinion" but you would seem to be of a mindset where a "heat pump waterheater" and perhaps "yet another minisplit for the family room" would be most suited to your direction of progress. An oil boiler which is not heating much of anything but your hot water has a lot of "standby losses" - i.e. keeping itself warm while ...


2

Six Things to Consider: Electrical - Generally easy to move Natural Gas (if it is a natural gas furnace) Output Air - might require one big duct between old and new but there may be alternatives. Return Air - similar to Output Air Combustion Exhaust Connection to air conditioner (if you have one) - typically a couple of pipes for input and output. Except ...


0

The smallest split I have seen is 12000 btu the issue may be drilling the 2” hole through the wall for the condensate and Refrigerant lines. There are even diy models out there that come precharged just have to hook up the power. I posted some info on this a while back if interested I will find the info several screws to hang the inside unit and the hole I ...


4

To check this yourself you will need an anemometer. Your furnace/AC system will have airflow requirements listed in the manual. Using an anemometer you can verify that the draw from your returns is providing sufficient flow for the requirements of the system. Typically you would make this measurement near the furnace intake by inserting the anemometer ...


7

Yes you should be concerned. When we size the duct work it is usually the minimum size needed. By reducing this opening you are affecting the furnace. Depending on the type you can cause enough excess heat to cause the safety’s to trip. Even if the safety’s do not trip the reduced flow can cause the fire box heat exchanger to run hotter (gas or electric) and ...


0

My suggestion is to record the sound , if using your phone take a video move the phone slowly to knee height , up to head height , move over a couple of feet and repeat. It may be a piece of flashing in the air handler that is not sealing well any that can make a heck of a racket , as far as the smell again it could be a seal. Take note of the outside ...


1

Since there is not any option to vent without extending the length of the vent hose I would try using a variable speed duct booster fan. You want to be sure you are not restricting the flow of warm air at all. To help ensure this check the temperature of the vented air on a hot day before adding any length. Then add your extension and booster. Adjust the ...


1

In most cases, you would have both a supply and return in the crawl. If the crawl is properly air sealed/encapsulated, then the air in the crawl should be the "same" as what is circulated in the home, so no issue with a return in there. If it's not properly encapsulated, then I would take the steps necessary to do so before adding a return as you may ...


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 ...


0

If the brackets are lag screwed into plywood, I wouldn't trust it. There isn't much meat for threads to work with in 1/2" plywood, and there is going to be some vibration from the compressor. If it's held in with toggle bolts, it will be very strong, I would not be worried about it pulling out. But I'd still rather not have a vibrating piece of ...


0

If you’re hearing the noise when the fan kicks on, it could be that too restrictive a filter is installed.


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 ...


0

I had the whistle in my last home ,, actually in my shop , the corrugated flex whistled when it was at full blast. Last try for tonight connect or ? Problems. I upsized from 3/4 to 1” flex and the whistle was gone, it’s the flow and the ripples that make the whistle, upsize the flex 1 size you double the area and noise gone, ok last time . ok this worked ...


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'...


0

The models I have installed have flow or pressure sensors that shutdown the fire box if an obstruction is detected. The control board may have some LED’s that show an abnormal condition. Usually to access the board an access cover needs to be opened, this has a switch that kills power, normally pulling out the plunger will energize the electronics, run the ...


0

I just installed a nest on an oldish furnace. If you read the documentation from Nest its says "it draws power from the leads leading to the furnace by briefly turning the furnace ON and OFF faster than the furnace is capable of registering. .... In most cases. However, in my case I had to run additional wires so I could hook it to a 24v transformer ...


0

Two points. First, be sure you are using a humidistat and not a dehumidistat. With a humidifier you need a control (humidistat) that shuts off the unit when the humidity gets too high. When you have a dehumidifier or HRV you need a control (dehumidistat) that shuts off the unit when the humidity gets too low. From your description your control just keeps the ...


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 ...


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 ...


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 ...


0

Don't over think it, it's simple. Bottom open during winter, top open during summer. My top ones don't even close. If the bottom ones are open that's where the majority of the air is drawn from Adjust Return Registers for Winter It’s important to remember that hot air rises and cold air falls. In the winter you want the cold air to be drawn ...


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 ...


0

Looks like your floor joists are manufactured I-joists, like this: https://www.fp-supply.com/st-louis-trusjoist-tji-i-joists.html If that's the case, they usually allow significant cutouts in the web (the thinner wood that connects the upper and lower flanges). You might be able come out the side of the rectangular duct up and through the joist, then over ...


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.


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

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

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 ...


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

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 ...


0

Great question and thank you for asking, but you clearly don't know much more about furnaces than I do and you really MUST call-in a Technician. Air-flow, filters nor flame dectection have anything to do with your problem and you could be risking the entire furnace with continued use. This/these sensors are vitally important and may simply need replacement ...


0

The reason chemicals are added is to prevent mold growth the mold can plug the drains and some kinds are hazardous. If the air handler is not being used you don’t need to continue adding. Just a note I would not use vinegar it is a weak acid and acids will shorten the life of the coils and etch zinc galvanized coating on the sheet metal. But if the system is ...


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 ...


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