(Heating, Ventilating, and Air Conditioning) For questions about installing, repairing, and troubleshooting HVAC systems.

learn more… | top users | synonyms

0
votes
1answer
37 views

Allergies and an economizer

I had an economizer added to my HVAC system last fall, which is fantastic for cooling my second floor down in the evenings during the shoulder seasons where the weather is cool in the late afternoon ...
1
vote
0answers
16 views

How to Change Chinese HVAC Thermostat

I am looking to put Nest thermostats in the house, I have now found out my entire house (one in each room, 6 of them) has been wired with HVAC Chinese U12A UNIVERSAL A/C CONTROL SYSTEM urrgh – they ...
2
votes
2answers
103 views

Should I convert from a rooftop to a split HVAC system?

We have a packaged HVAC on the roof and the AC needs to be replaced. It's 23 years old and dying/dead. We were considering buying just an AC and keeping the package unit running for heat. We feel ...
1
vote
2answers
28 views

Is having a branch off the end of main heating HVAC duct bad and if so, why?

Question: Is having a branch off the end of main heating HVAC duct bad and if so, why? Background: A heating and cooling contractor sales representative came to my home today. He saw the situation ...
2
votes
1answer
58 views

Should I be worried if my A/C ran with the cover on?

My wife accidentally switched on the "cool " mode and the a/c was activated, however the cover was still on the unit outside. Ran like this for about 2 hours. I noticed it and turned it off and went ...
1
vote
3answers
55 views

How to hide AC lines up against brick siding

I had this AC system installed, and didn't realize when asked about what location i'd prefer the compressor that it would look so ugly having it off the corner of the building instead of in the middle ...
0
votes
1answer
28 views

Smart Thermostat - No C-Wire - No Controller Board

This one seems to be a little different from previous questions on the subject. Here is the dilemma, I don't see a transformer. I have included a few pics. There are Three wire bundles. For ease ...
1
vote
1answer
23 views

How can I add a C wire with this unusual installation?

I recently got a new Honeywell WiFi thermostat, which requires a C-wire. I have 5-wires going to my current thermostat, with only 4 being used. So I thought adding the 5th as my C-wire was going to ...
1
vote
1answer
49 views

HVAC contactor sparks when AC kicks?

The HVAC and control board is a McQuay Mark IV. I'm not sure if I would like to try and fix this myself yet. Just trying to figure out the issue before deciding where to go. Here's the scenario: ...
1
vote
1answer
34 views

What should I do after a low-voltage wire was cut putting the furnace door back on?

I have the basic Honeywell thermostat that a lot of people have. All the thermostat wires go to the blower in the attic (for the central air). They are spliced with wires that then go to the furnace. ...
0
votes
0answers
32 views

Why would my AC turn on and off randomly?

My AC unit turns on and off randomly regardless of whether the thermostat is set on or off. I've even tried removing the batteries. Does anyone know why this might happen?
1
vote
0answers
38 views

How can I use a portable A/C unit to cool my clean room?

So, I have built a room inside my shop, a clean room for finish and airbrushing. I want to cool this room as I spend more time in it than the rest of my shop (garage) So, I get a portable unit. ...
1
vote
1answer
40 views

Appropriate register for duct size?

So I asked a long-winded version of this question in another thread, but haven't really received any good responses yet. I'm going to condense and try again... There is an 8" duct feeding a 6x12 ...
3
votes
1answer
32 views

Can I replace my draft inducer blower with a model of a slightly different speed?

My furnaces draft inducer blower sounds like a snow blower running, so I set out to replace it. Finding a replacement part proved difficult, but I found a site advertising a compatible part and ...
0
votes
0answers
49 views

Would increasing the size of the A/C duct for my kitchen improve cooling?

As part of an ongoing kitchen project, I'd like to relocate the existing a/c register in the ceiling (which is located next to an interior wall) to the center of the room and upsize the duct (and ...
1
vote
2answers
67 views

On a thermostat, are “R” and “Rh” terminals the same thing?

I have an older thermostat controlling an old ass Trane furnace with A/C. It has an "R" terminal and an "Rc" terminal (they are jumpered - see photo). I see references to an "Rh" terminal online. Are ...
2
votes
1answer
37 views

AC not cooling using heat pump

I just bought a house and this is my first experience with using a heat pump. I have put in several hours of research and understand how it works but I need someone that has experience to give me some ...
2
votes
2answers
52 views

Are there optimal positions for A/C and heat register grills to be facing?

I noticed a while ago that some of my A/C and heat register grills are facing the walls and not the room (the insides of the curves on the grills face the walls) in some rooms but not in others. My ...
1
vote
1answer
82 views

Connected C-Wire to new Smart Thermostat and Furnace board and still no power

I need help. I've been surfing the internet and have had no luck finding answers to my situation so am hoping for some guidance. I've seen other questions here answered but none that suit my ...
0
votes
2answers
65 views

Why do I have to start my furnace manually every morning?

The oil furnace works fine all day and evening, then overnight I have the programmable thermostat lower the temperature at 11pm. But every morning at 5am when the thermostat tries to turn the ...
3
votes
1answer
49 views

Why would my boiler expel steam when it's set at 180F

So, I have recently had some issues with my boiler (hot water - not steam) system. After hiring some guys to stop by and take a look at it, they told me that the boiler pressure reducing valve, ...
1
vote
1answer
177 views

Adding a C/Common wire to HVAC system

So I'm looking for some help in identifying where I can attach a C/Common Wire to my HVAC system, but unfortunately my system doesn't have a control board that I can easily attach a powerkit to. For ...
1
vote
1answer
33 views

Why is it taking so long for my A/C to start?

When I turn my AC thermostat to cool, I can hear it click but the outside unit does not start and no air blows inside. Several hours later everything turns on and it works fine. If it turns off, ...
1
vote
1answer
27 views

Good replacement actuator?

I have 2 Belimo actuators that control dampers for A/C ducts in my house that the motor has gone bad on. I can't find much info about the model "LM24-T US" so I think it has been discontinued. I ...
1
vote
1answer
36 views

Sound proofing HVAC ducts

We have an HVAC system in our house where the duct work is all sheet metal with no insulation on the interior of the ducts as all of it is buried under inches of foam roofing insulation. Works great. ...
1
vote
1answer
60 views

HVAC replacement

we just recently purchased an older home- 1978 - 2200 sqft, 2 stories, 2 14x20 returns - one downstairs, one upstairs, 5 ton 10 seer system, 10yr old goodman air handler but the condensor is unkown ...
2
votes
2answers
17 views

How can I install Air condiitoning timer

want to install a timer on split air conditoning unit to accomadate my energy plan hours, too many people change the thermostat. could another thermostat be used at the pump, controlling one of the ...
2
votes
2answers
102 views

How should I wire a Trane air handler & heat strips?

Looking for validation or correction on my understanding of requirements for wiring 5 ton Trane air handler with 20kw heat strips. Of course, I read the label and identified that there are (2) 240v ...
1
vote
2answers
70 views

How can I use a WeMo controller on a non-standard outlet?

I have an older A/C unit that uses a 6-15p plug. I want to be able to remotely control the unit with a WeMo, but it uses a 5-15r receptacle and plug. The A/C unit says its rated for 208V, and I ...
3
votes
1answer
56 views

Is there a wireless way to cut off the HVAC y wire from my generator transfer switch?

I recently had a Generac Synergy generator installed, which went smoothly, however there was no good way to get the Y wire from my thermostat to the transfer switch and back in order to allow the ...
3
votes
5answers
127 views

How can I vent a portable air conditioner when there's no window?

My shop does not have central air and does not have operable windows. There is a steel door in the back and cinderblock walls. My landlord is against me cutting a venting hole in either the steel ...
2
votes
1answer
33 views

Can I use a power gable fan and ceiling louver vents to pull cool air into my house?

I live in L.A. We only have really hot weather 5-10 days a year and it usually cools off at night (outside). I also have a large Gable vent in my attic. (recently added with addition) I would like ...
1
vote
2answers
99 views

Furnace blower motor won't turn off

I've replaced both limit switches on my Comfortmaker furnace plus the control board. Blower continues to run and the unit will still heat my home. Component changeouts did not make a difference in ...
2
votes
1answer
123 views

Is it possible to add a “C” wire to my electric heater?

I bought a Wifi Thermostat but my old thermostat did not have a Common Wire. I can't use any of the swapping the G for the C solutions because I have an electric heater. I was told by Honeywell that I ...
0
votes
0answers
29 views

What to look for in central air installation?

I'm having an HVAC company install a York central air unit in my house today, and I'm wondering what things I should be looking for in the quality of the installation? Existing York central heating ...
7
votes
1answer
103 views

Decrease dust in an old house, forced air

My house was built in 1940. I have noticed the forced air pushes out a lot of dust. This is evident from lint collecting on the bathroom vanity below a vent. It only collects lint during Summer and ...
4
votes
2answers
48 views

Solution for fiberglass ducts that have collapsed in basement?

I have two furnaces in my house, one for the basement and one for the rest of the house. I noticed that while using the basement furnace this winter that no air was coming out of any of the basement ...
1
vote
1answer
42 views

What should I do with an unused C wire when installing a thermostat?

Replacing a Carrier programmable with a Honeywell RTH6350D1000. Carrier had blue/gray wire in the C connector. Honeywell does not have a C connector. In install book "Advanced" wiring it says to ...
1
vote
1answer
50 views

what is this unused brown wire in my thermostat wiring?

I replaced an existing Honeywell programmable thermostat with a new Z-wave enabled CT101-L thermostat yesterday. All went well, and the C, W, Y, R and G wires found their proper target connectors. The ...
0
votes
1answer
57 views

Fan coil wiring problem with new thermostat

I'm trying to upgrade to a new line voltage thermostat. The new thermostat has many more connections, including three fan speeds. My current system has a manual fan switch on the wall so all I need ...
1
vote
2answers
322 views

HVAC Duct options in floor joists

I will explain what I would "Ideally" want. I would like the HVAC in the basement ceiling to Not require a soffit. Plumbing seems possible because the holes for the most part will be small enough to ...
1
vote
1answer
39 views

alternative to packaged unit downstairs

House built in 1922. Never had central air. Heated with hot water boiler and rads. 2 stories, 1569 sq ft. Salesman recommended split sys upstairs and packaged sys down. Only appx 22 inch clearance in ...
1
vote
4answers
103 views

My house has electric heat, built in 1969. How can I save $. Are solar panels the way to go, or is there something better out there?

I'm not sure which way to go . My electric bill is nuts. I have a fireplace and it helps, but it only heats one room. Are there any good solar panels on the market? I thought about geothermal but I ...
1
vote
1answer
54 views

Is my HVAC system unbalanced?

I bought a home back in August and the previous owner had a new 3-ton HVAC system installed. Basically right now the HVAC is located in the upstairs hallway, and the way the duct is set up is there ...
1
vote
3answers
806 views

How can I heat up my apartment to kill bedbugs in Southeast Asia?

I have a bedbug problem in my apartment and I want to fix it myself with heat. (I do not want chemicals sprayed around.) Apparently, getting a room to 140 degrees for two hours is sufficient to kill ...
0
votes
1answer
47 views

What could be causing a moth ball like smell?

We have a smell like moth balls in bedroom of condo. Moth balls and camphor smell coming from heating unit in bedroom.
5
votes
3answers
293 views

How can I improve second floor HVAC performance?

I have a forced air heating and air conditioning system that performs poorly on the second floor: It is way too warm in the summer and a little too cold in the winter. I live in a 1920s masonry row ...
13
votes
2answers
3k views

Can I run a central air conditioner in the winter?

What happens if you run a central air conditioner when it's below freezing outside? Is this expected to work? I know, it sounds crazy, but that's because you don't live in an overheated New York ...
0
votes
0answers
20 views

Why does the A/C come on downstairs when heat is on?

I just moved in to a 2-story house. It is zoned upstairs and downstairs. If I turn the downstairs thermostat to OFF and the upstairs to COOL, the HVAC in the attic comes on, the outside compressor ...
0
votes
1answer
90 views

What if my Trane 3 ton 13 seer heat pump is unable to generate enough heat to reach the set point on the thermostat?

The unit turns on when thermostat temperature is set higher than room temp. It blows cool air for several minutes and then the emergency heat kicks on and warmer air comes from vent. This lasts for ...