New answers tagged hvac
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Can I have a separate thermostat for a wood boiler?
I Have an outside wood boiler. The circulating pump runs 24-7. I just replaced my old furnace last August with a new furnace that has a Lennox circuit board. With my old furnace, I added a White ...
2
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Why would part of my second floor not have any HVAC airflow?
So finally figure it out.
One vendor removed 1 Zone dampers (top floor) ( which was not the issue ) , then he said "I don't know". SO I kick him out and then study whole system and figure ...
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Bathroom Fan switch ground vs Neutral
Neutral is a separate system altogether. It comes from the utility transformer, to your panel, to your outlets. It is the normal path of power.
Ground comes from the ground rod, to your panel, to ...
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Bathroom Fan switch ground vs Neutral
The code (NEC) was changed in 2011 so all new switch boxes must have a neutral wire to them, so smart switches can be used. Many jurisdictions are regularly several years behind the latest NEC. Right ...
- 17.1k
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What is this thin steel wire connected to the ungrounded side of a two-wire cable in my basement ceiling?
It looks like simple half of the bipolar antenna (horizontal antenna) used in CB radio communication.
It operates in 27 Mhz range.
Since its total length is 11+11 feet it is difficult to hide outside.....
- 11.2k
15
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What is this thin steel wire connected to the ungrounded side of a two-wire cable in my basement ceiling?
Appears most likely to be an old long-wire Radio Antenna. Likely run through the duct to get to where the receiver was. Unlikely to have been a transmitting antenna.
Typical of "crystal" ...
- 166k
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How bad is it to have low spots in a mini-split line set?
Think about this from a physics point of view.
A siphon does not care about anything but the relative height difference between the inlet and outlet.
Imagine a scenario where a heat pump line has to ...
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Find replacement HVAC transformer
The single red wire makes no sense. It may be a leftover from a previous configuration - along with a black or white wire that was removed.
As far as a replacement, the main consideration is voltage. ...
5
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Find replacement HVAC transformer
Any 24 Volt transformer will do.
The higher the wattage rating, the better to prevent overload. A wattage should be in the range of 30, 40, 50 watts, and is measured/labelled in VA or W.
Do not ...
- 11.2k
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In practice, is it problematic to vent a gas-fired boiler under a bay window?
Generally speaking...
The exhaust from a power-vented appliance usually exits at high enough velocity to clear that distance.
The exit termination is probably nearly the 17" anyway.
Moisture is ...
- 115k
0
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How to waterproof foam and pipes coming up through concrete ground
It's closed cell foam (or should be) - so water getting into it should not be an issue - worry more about the gnawed-off sections and get to replacing them, perhaps with a metallic over-wrap to slow ...
- 166k
4
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Which breaker controls the HVAC unit?
In a rental unit you need permission from the landlord to do any work. Legally the landlord can make claim to any appliance you install on the building.
To place a smart thermostat, you need to ...
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Which breaker controls the HVAC unit?
5/7 is labeled heat, but heat is actually a furnace of some sort which includes an air handler. That air handler is also used by the air conditioning on 2/4. To play it safe, turn both 2/4 and 5/7 off....
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Inducer motor is not spinning
The problem was my control board. It had at least one burnt-out relay. After changing the board, everything started working.
Thank you.
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Gas furnace takes like 2-5 minutes from ignition to blower start. flame also burning yellow/orange
I found the manual for that furnace here. It says:
Observing Burner Operation
1.Observe burner to make sure it ignites. Observe color of flame. On natural gas the flame will burn blue with ...
- 600
11
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Gas furnace takes like 2-5 minutes from ignition to blower start. flame also burning yellow/orange
The flame should be blue with some orange tips, if not it is more than likely a serious problem.
From your description it does not have enough oxygen - thereby depositing a lot of carbon on the inside,...
- 5,583
4
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Gas furnace takes like 2-5 minutes from ignition to blower start. flame also burning yellow/orange
It may be that this behavior completely normal. Most forced-air furnaces have a thermostat inside the furnace that, when it detects that the gas is burning, turns on the blower. And it continues to ...
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Zone 2 smart thermostat c wire voltage question
In order for the zone controllers to work both have to be on to distribute air flow between them. With only one zone on, you have no zone controller. That is why the zone 1 controller has to be on all ...
- 11.2k
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blower moter on my hvac dosent work after changing both capacitors
Could it be that you reversed which capacitor goes where.
They capacitance are not the same.
As you pointed out you have two capacitors.
One is for the motor start (the larger capacitance one) the ...
- 11.2k
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blower moter on my hvac dosent work after changing both capacitors
Despite a world full of people who are sure the only possible problem with a motor must be a capacitor, there are other things that can fail. Control systems, starter switches, insulation failure, bad ...
- 166k
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AC Condensor Motor Wiring
The wiring diagram on the motor pictured calls for a capacitor (7.5 µF and 370 VAC rated) between brown and brown/white.
Line goes to black (so line 1 and line 2 if 240V, or line and neutral if 120V) ...
- 166k
2
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Can I use rigid metal 90s with flex duct?
As RMDman noted you probably don't need to do this at all.
If, however, you are bound and determined to replace the flex bends with metal ones, each metal corner will take two pieces:
An appropriate ...
- 37.2k
5
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Can I use rigid metal 90s with flex duct?
I have seen hundreds of homes here in FLa. with the duct-board and flex ducts you describe. None have ever had metal 90 degree parts for bends.
They are not pulled tight so as to allow adjustment and ...
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Why does hooking voltmeter to two transformers show 0 voltage?
To measure voltage, you need a complete circuit.
Connect a voltage meter between a hot 120V wire anywhere in your house and a neutral wire anywhere in your house and you will get 120V because the ...
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Why does hooking voltmeter to two transformers show 0 voltage?
In a nutshell, the secondary voltage is a result of the field created in the windings around the core of the transformer. If you leave the core, you lose the voltage.
- 68.9k
4
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Why does hooking voltmeter to two transformers show 0 voltage?
Transformers are magnetic devices. There is no electrical connection between the secondaries (the low voltage side), so what you are seeing makes sense.
- 20.7k
3
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Why would a plug-in radiator appear to be much more effective than a PTAC unit?
There are a number of issues here, some of which have already been mentioned in comments but I will try to summarize and explain a bit more.
TL;DR Way too many unknowns, but it is likely that the PTAC ...
5
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Should an inverter heat pump be sized according to the conventional AC unit it replaces?
"The ability to throttle the compressor speed" typically (in a good unit) means it can run from rated capacity to about 1/4 rated capacity (so 48K-12K in this case) and below 12K it will ...
- 166k
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What would cause a furnace to randomly fail to light roughly once a week?
Is your water heater on the same gas pipe as the furnace?
It's possible that your gas pressure at the furnace is marginal due to inadequate pipe size or excessive distance, and if the water heater ...
- 7,616
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What would cause a furnace to randomly fail to light roughly once a week?
There are two classes of problems here; you'll have to figure out which one you're facing.
Flame proving failure
This means that the gas does ignite reliably but the furnace controls aren't able to ...
- 23.5k
3
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Heat pump for additional heating capacity in downstairs of house
Your heat pump plan is solid, but to some degree, this is a bit of an XY problem. Your existing central system is performing poorly, but instead of asking how to make it work better, you're reaching ...
- 23.5k
3
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Heat pump for additional heating capacity in downstairs of house
First: all electric resistance heat will have a COP of 1.0. It's the nature of using electricity to directly make heat.
Second: given everything you've laid out, adding a heat pump to the basement ...
- 4,319
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Heat pump for additional heating capacity in downstairs of house
Naturally the upstairs will be hotter than downstairs.
Hot air rises.
Limit or stop hot airflow from downstairs to upstairs, by closing the doors ect. The more you insulate the less hot air will be ...
- 11.2k
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How is a "Split" Air Conditioner Heat Pump System different from a garden variety Heat Pump?
In America, the air conditioning business was a huge thing for at least 60 years. The vast majority of American homes have A/C, while it is rare in Europe with similar per-capita GDP. The production ...
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