New answers tagged hvac
2
The contactor is probably stuck closed. You should shut the breaker off immediately to prevent a fire. There's a high limit switch but that won't do any good if the contactor is mechanically stuck closed.
-1
Without nameplate data it's hard to give you an accurate answer. But 100 amps is enough to power most average size households so I'm guessing you'll be fine adding the additional circuit.
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See that tee fitting at the lower red arrow? That's the condensate output from the furnace. Burning gas in the winter produces liquid condensate in the furnace exhaust pipe; the condensate drains back into the furnace and out through this point.
The burner condensate drain is the lowest of the three water sources shown here. If you can re-arrange the drain ...
3
The feeder needs to be correctly breakered at the supply end.
That is 2 AWG (33.6 mm2) aluminum AA-8000 feeder. It is only good for 90 amps.* If the supply breaker is 100A, that's a common blunder due to misreading NEC. Change the breaker to 90A.
Determining whether you have the amps to spare
And adding a 20A to this subpanel is fine given that it's ...
2
The datasheet for your panel says it is a 6 slot, 12 circuit panel, which means it should be compatible with tandem breakers. A tandem breaker is two small breakers that take up the same slot as one full sized breaker.
But you have all double-pole breakers... Well, they make a solution for that too which is two tandem breakers joined together. The middle ...
0
Most minis that I have installed use TC cable.
The compressor and controls are 240v but the voltage on the inside unit can be different.
If the unit is listed by UL / or another 3rd party agency and they specify the SJOW it is legal to use the cable/cord.
The W in sjow is for water resistance water will not be a problem with this cable.
Last make sure you ...
2
I can think of nothing in the national electrical code prohibiting such an installation.
0
I would recommend cold weather foil tape. That stuff sticks to everything. You could also use epoxy resin tape (Tuck Tape) uses on Tyvek on exterior walls. Both stick to just about everything.
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The C wire is one side of the transformer and the R wire is the other. The R wire feeds the signal into the thermostat where relays connect that voltage to G (fan), Y (cool) and W (heat). In the furnace control board, G, Y and W are sinks not sources, so you should get a small voltage reading or zero, depending on your meter from R to any of those three. You ...
4
if you have a clamp meter you can check the current draw of the compressor.
A too high current indicates either a stalled compressor or the compressor spinning freely not doing any compressing.
It is also possible that an internal part of the compressor failed which would also need replacement of the compressor.
Replacing a compressor requires both ...
2
The insulation the contractor is referring to, is the insulation on the heat pump refrigerant lines. *
This is not the fiberglass or rockwool insulation that homes have to keep out the outside cold/hot. That would not normally exist between interior spaces, anyway.
It's a tubular pipe insulation that goes around the pipes. It works best if it is a vapor ...
answered Sep 14 at 19:26
Harper - Reinstate Monica
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2
The only thing that could be happening in this case is a broken wire, or a bad splice. A solid, continuous wire will have voltage on the other end, even if its partially damaged. A damaged wire will not have the current carrying capacity (amps) that a good wire does, but it will show voltage. Also, since this is alternating current, the 2 volts you're ...
2
Today's heat pumps blow gas out of the water for you, especially given how awful your new furnace is
Given your location, the current rates your utility provider (KUB) charges of $1.0189/therm for all therms of gas over the first 30 (and higher for the first 30 therms) and $0.09186/kWh for residential electricity (or lower for offpeak), 23°F for your ...
1
There is not. They're pretty easy to pop off, so I just pull mine off and plug the back into a standard USB charger.
0
Vents are best as big as possible. It is easy to reduce the flow of a vent, but difficult to increase it.
An 8" round = 4x4x3=36 square inches for air to flow through.
A 4x12 square = 4x12=48 square inches for air to flow through.
A 6x10 square = 6x10=60 square inches for air to flow through.
A square duct does not pass quite as much air as a round duct....
2
It's most likely to be an induction motor. Its speed depends on the frequency of the AC supply, not the voltage. To reduce its speed you'll need a lower frequency. A variable frequency drive is the "normal" way of achieving that, but you might be able to hack it by, for example, adjusting the governor on a portable electric generator to reduce ...
5
Problem #1: It can kill you
If you have a modern, competently built house, you have a very tight house that does not like to leak air from outside. That is for heating/cooling efficiency. Air is a thing, it's not just magic. If you push air out of a well-sealed house, it will draw a vacuum on the house, just like charging an air compressor tank, but in ...
answered Sep 9 at 19:29
Harper - Reinstate Monica
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6
Are you sure that contractor is not secretly a hitman? I give him props for creativity, that's for sure!
On a serious note, furnaces with efficiency of less than 90% must be vented via metal pipe above your roof line. The exhaust is hot and extremely gaseous. You don't want the gases creeping into your house through your eaves/soffit nor an open window/door. ...
0
Oxygen is burned during heating process. If air circulating in closed volume, after time oxygen percentage is down. It causes lower efficiency of gas heater.
28
HELL NO
Whichever joker is installing an 80% furnace with a PVC pipe for the exhaust needs their license revoked pronto, because that's a patent CO hazard. Non-condensing appliances operate at flue temperatures well above the safe working temperatures of PVC or any other plastic, and thus need to be vented using a metal B-vent. (Conversely, condensing ...
0
For the A/C zones -- Nests need the C wire from the cooling side
One downside of the Nest in a two-transformer application is that it requires that the C wire come from the same transformer that is powering the cooling side of the house (Rc, Y, G, O/B). Fortunately, this works for the two Nests you have that are controlling both heating and cooling, so you ...
0
Condition, as I understand:
Your furnace is in the basement.
You want an intake in the basement.
You have a 12 inch metal duct to go from the furnace to the return.
You have a 14 inch by 14 inch grill.
You want to give the basement enough return air.
Is the intake grill large enough?
...also...
You have four 5 inch flex exhausts.
You used the larger 10x4 ...
1
What is your end-goal exactly, get new refrigerant for next to nil?
He indicated that he may be able to reuse the same refrigerant if he finds that it hasn't been too contaminated once he recovers it and the pipes look clean (if the compressor oil didn't mix with it).
Sounds like this person is trying to be nice and looking to save you a few bucks.
I ...
4
Replacing the ductwork shouldn't be extremely expensive. Even if it was moderately expensive, I'd still do it.
Mold/sewage/ etc is nasty.
2
Make sure the filters were installed in the unit. They are sometimes left out during construction when the units are tested due to all the dust. they might have forgot to install them. If they are there, clean them or replace them. Not really a good idea to disable ventilation units.
1
If your ventilator is exhausting air from the apartment, then air (and dust) are being drawn in someplace. If the ventilator filters air and discharges it back into the apartment , it is not a problem.
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This is merely a way for them to jack up prices and force you into paying $400 for a job you can do yourself for $20
I have charged my system many times and it's fast and easy using only a $49 set of guages.
1
This is far more serious than secondhand smoke
The issue with your HVAC return is far more serious than getting a load of dank from the downstairs neighbors, as if that can happen, then the smoke from a working fire can also invade your apartment, and that's a much more acute health hazard than anything a bunch of smokers can produce. Note that this threat ...
1
We have sheets of neoprene insulation as thin as 1/8” all you need to do in reality is prevent condensation even spray foam in the hole allowing it to encapsulate the lines will be enough.
Don’t worry about your tape skills you are really just preventing uv exposure as this breaks down the insulation.
Tape also seals from air movement again helping to ...
0
The thing to consider is that each thermostat is getting power from somewhere, and where the C-wire comes from needs to match that. For the furnace thermostats, the C-wire needs to come from the same transformer that the red wire comes from. Its possible that multiple units share a single transformer, but that's not likely. I would assume that each unit ...
2
TL;DR
Check your lease and state regulations for a "Repair and Deduct" clause. You might be within your right to schedule a repair yourself and deduct it from the rent.
Aside from it being vehemently disgusting I would classify indoor second-hand smoke as a fairly serious habitability problem. You might consider reporting it to the health ...
1
Are you planning to purchase an existing home or build your home from the ground up? If building from the ground up it might be interesting to look into geothermal climate control.
0
You could put a "T" there but be sure the stub is long enough to be above the pan, if not water will run out. Also place a cap, not glued or anything on the stub, otherwise cold air will escape. It is best to design it so the vinegar does not run back into the pan. Then when cleaning you remove the cap, pour in the vinegar and replace the ca. Happy ...
1
It's true that a swamp cooler and a humidifier (together with its associated furnace/air handler) both have "blow air around" and "make the air wet" on their lists of features. But the scale at which they do those things is so different that it doesn't make sense to have one piece of equipment do both jobs.
Furnace air flow: about 1000 ...
3
The corrosion/patina on the copper might seem like a bad thing because you're used to rust on steel, but it's not the same process. Rust on steel doesn't form a good bond on the metal, it expands, and it flakes off, exposing more steel that then rusts and flakes off, etc. It's a destructive process.
Copper an aluminum corrode much, much slower because the ...
1
It sounds like flex duct it is soft with a wire to keep its shape insulation and another inside layer of the black plastic.
Make up air ducts can not be in flex there will need to be a hard pipe for a duct to take off. When I put these in they are usually close to the furnace air handler, even on the air handler a simple hole with an adjustable metal cover ...
0
I'm also an HVAC novice, but this article is a good explanation of how air may or may not be drawn in, depending on the design of your HVAC system: https://pharoheating.com/hvac/is-it-bad-to-run-my-furnace-fan-all-the-time/
I would also recommend getting an air quality sensor (e.g. Purple Air, etc.) so that you can directly see whether wildfire smoke is ...
0
Most contractors in my area use “plastic pads” never set a unit on loose gravel
If you are setting the unit on rock it should be compacted shale or crushed quarry! pea gravel will move “FOREVER “ ok just the opinion of a guy that did this for a few weeks over the last few decades.
0
I would use lightweight cinder blocks similar to this.
0
The smaller stone will compact better and you will want to compact it. Depending on the slope of the hillside, You might need to build a small retaining wall to keep the erosion from washing the stone away causing the pad to tilt.
2
Imagine you had a working thermostat and you flipped it to "A/C" and set the temperature to 50F. The thermostat would "call for cooling" so long as the temperature is above 50F. Since I bet your system would never get there, that means it would "call for cooling" continuously. That is fine. If your heat pump unit can't run ...
answered Aug 27 at 20:28
Harper - Reinstate Monica
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1
Consider the options these upgrades unlock
The conversion from tank to instant water heating can free up substantial space on the floor. It might cause you to think about reconfiguring the room (positioning of work bench and other furniture/storage).
Some tankless water heaters use a single concentric type vent. That's an assembly of two pipes; the inner ...
3
After the circuit breaker failed too, I was forced to call out my HVAC guy who installed it last year, so I suppose I have a definitive verdict now.
It was in fact a bad capacitor on the compressor, just like in this question with very similar symptoms to mine. It was still under warranty, so no problem there.
Of course the circuit breaker was probably ...
2
The sensible order of operation is:
Switch to high-efficiency appliances first since their exhaust will be routed via PVC through your rim joist
This will eliminate your appliance dependency on your chimney
I don't know your budget. If you want to do the furnace and water tank at the same time then great or you can stagger them.
Water heaters should be ...
2
Let me start by saying I am not an HVAC professional. But I’ve dealt with this a few times before.
The chimney liner may not be be necessary if you are upgrading both your water heater and furnace as neither will likely vent through the chimney. The tankless definitely will not. If you go with a high efficiency furnace, it cannot use the chimney either.
...
6
If your AC unit was running correctly before the thermostat failed, then it will be OK to run it continuously until the AM when you plan to shut it off. Just don't freeze tonight because it won't be cycling on and off. When weather is extremely hot, AC units can run continuously and many do down here in South Florida. Just replace the thermostat as soon as ...
4
Considering that the unit has a microcontroller-based control board (unless it's really old or really old-tech) then yes, things like brownouts or other transients can cause it to get into an odd state and a "reboot" may help.
It's not the compressor itself but the electronics that are controlling the compressor.
0
The furnace that the A/C is installed on is probably just a heating furnace and not a furnace with a large enough drive (blower). Without knowing the furnace specs, we can only guess as to a solution to your problem. Whoever installed this A/C unit did not do his "home work" before the installation. A 1/5 hp motor is almost never going to provide ...
2
I know this thread is super old but I hope it can help someone else seeking answers. I had the exact same problem, random parts of the house had electricity while other didn't. At some points the lights were flickering, then they stopped. Refrigerator and microwave worked but stove didn't. Checked the box but that wasn't the issue. Shortly after I received a ...
1
Use a twist lock plug and socket. Here you first plug in and then twist it clockwise to lock it in place, and then you have to twist it anticlockwise before you can take it out.
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