Skip to main content

Questions tagged [air-conditioning]

For general questions regarding cooling your home.

196 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
2 votes
0 answers
204 views

Adding return air vents in bedrooms to reduce return air noise and increase total return air capacity

I did my homework here the best I could and I hope someone can help by checking my work. In an attempt to make things as clear as possible, I made the following diagram. This is my existing system ...
deefofum's user avatar
2 votes
2 answers
271 views

External furnace fan switch energizes AC

2010 house and thermostat. White Rogers 1F80-361 controlling a lennox furnace. We have a fan switch located above our Tstat that will turn the furnace blower on and will also energize a make up air ...
Dan's user avatar
  • 29
2 votes
0 answers
62 views

Is there something wrong with heat pump + Empire furnace?

I've been asked to look into A/C for a 1600 square foot building at our lodge. The gas furnace is old and tired, and on its last legs. There is a top floor that is 2 rooms subdivided, and a well ...
Harper - Reinstate Monica's user avatar
2 votes
0 answers
123 views

Wall A/C unit runs partially after turning off and eventually trips breaker. Is it a stuck relay?

I have an in-wall A/C unit that has been getting a workout in this 90 degree weather. It's a Kenmore Model No. 580.74124400. 115v 11.5A on a 15A dedicated circuit. I've now had two instances of the ...
Logarr's user avatar
  • 352
2 votes
0 answers
164 views

Why would a wall-mounted AC unit with a digital thermostat seem to be reading outside temperature when the fan isn't running?

My apartment has a wall-mounted AC unit with a digital temperature setting, which works great, but it has a consistent problem where its thermostat appears to read much differently than the actual ...
Mejwell's user avatar
  • 121
2 votes
0 answers
91 views

Thermostat wiring for ac

I recently installed a nest thermostat for our AC system. Unfortunately I was short sighted and just assumed all the wires were the color I needed. Since installing the thermostat our system won’t ...
Tim Rozendaal's user avatar
2 votes
0 answers
4k views

Why does my outdoor AC unit make a screeching sound when it shuts off?

MY AC cools just fine. But when it cuts off, the loud screeching sound outside can be heard from far away. This only happens when the AC goes off. There are no other weird sounds, any other time. ...
Georgia's user avatar
  • 21
2 votes
0 answers
874 views

How can I insulate and elevate an A/C line set on a flat rubber roof?

The Scenario An apartment building with a flat black rubber roof. The A/C condenser is on a platform on the roof with an air handler inside the unit. The line set runs across the roof for about 20 ...
EBarr's user avatar
  • 121
2 votes
1 answer
244 views

New thermostat: How to wire it?

My old air conditioner thermostat broke down, so I bought a new one. But when it arrived, I was horrified to discover that the terminal of the wires were not named the same. Both thermostats have ...
Legisey's user avatar
  • 106
1 vote
0 answers
29 views

Insulation and A/C system selection in a metal shed

I've got a 20x30 metal shed that I'm trying to finish out as an ADU. I don't know enough about insulation and A/C to choose what to install. The construction will be as follows from exterior to ...
Skyler Kovacs's user avatar
1 vote
0 answers
29 views

Troubleshooting Samsung AC error code

recently my Samsung AC unit (model AR12RXFPEWQNEU) started throwing error E251 repeatedly and won't start. So I looked up the manual and saw that the issue was related to the temperature sensor in the ...
Warrior's user avatar
  • 111
1 vote
1 answer
31 views

Should I be concerned about possible mold on/near my window ac unit?

https://imgur.com/a/EQEQnQq Hi all, I’m moving into this historic house and see this around the ac unit. I don’t notice mold anywhere else. Does possible mold around the ac indicate a mold problem in ...
fox's user avatar
  • 11
1 vote
1 answer
41 views

Nest Power Connector (C Wire) on A/C unit GMP075-4

I’m trying to use a Nest thermostat on my older Goodman GMP075-4 unit. I have a Y, R, W, and G connector for the thermostat. I’ve read through a few number of the other questions related to this on ...
ariagno's user avatar
  • 111
1 vote
2 answers
289 views

A/C vent not connected to duct?

So I am in the process of doing a light reno to a bathroom in my 1954 ranch style home and I took off the a/c vent to wash it and/or buy a new one. To my surprise (okay not really surprise— there was ...
Olivia's user avatar
  • 11
1 vote
0 answers
49 views

How can I troubleshoot a dehumidifier evaporator which frosts up quickly?

This dehumidifier is about two years old. The evaporator is icing up almost immediately after turning it on. This picture is about 20 seconds after turning it on. After about an hour the bottom ...
jay613's user avatar
  • 40.5k
1 vote
0 answers
192 views

Multi-split Daikin air-conditioner errors and temperature issues

I have two indoor Daikin Perfera FTXM-R units hooked to a 2MXM-N9 outdoor unit. What I noticed is that the indoor unit closer to the outdoor unit (A) will start to report a very low temperature if I ...
Andrei Pietrusel's user avatar
1 vote
1 answer
66 views

Two Identical A/C Units with Different Readings / Pressures not Stabilizing When Off

I have two separate systems with one in the basement servicing the main floor, and the other in the attic servicing the upstairs. The upstairs has been struggling in 90F heat ever since we moved in ...
JSess's user avatar
  • 185
1 vote
0 answers
191 views

Fan motor capacitor replacement

Could I get some help replacing this blown (and very smelly) capacitor from an air conditioner? It's for the fan motor. The part is available here https://rmscomponents.com.au/shop/appliance-spare-...
John M.'s user avatar
  • 249
1 vote
0 answers
245 views

I need assistance converting thermostats from a Honeywell RTH2300B1012 to Honeywell RTH5160D1003

I currently have a home with 3 zones and a central A/C and oil-fired forced hot air. The way the system has always worked in the main stat has to be set to heating or cooling for the others to run ...
ChessClubRebel's user avatar
1 vote
0 answers
167 views

C-Wire Adapter without Y wire on board

I was looking to get our AC thermostat replaced with a smart one. We have an outside unit, upper unit, and the thermostat. I checked it out and no surprise, there was no C-Wire in use or hidden ...
Corey's user avatar
  • 11
1 vote
0 answers
483 views

Mounting external component of split AC on hollow brick wall

I have a small split system (Philco Phs25ha4cpi). The external component weighs 25kg, and I have mounting brackets like these: And a wall made from bricks like these: My question is what kinds of ...
EmmanuelMess's user avatar
1 vote
4 answers
4k views

Musty smell from furnace

When switching from cooling to heating in the fall we get about 2-3 days of musty air and then it's fine all winter. It's like wet sock/sneaker smell. Yesterday, the A/C kicked on because our house ...
MonkeyZeus's user avatar
  • 16.7k
1 vote
0 answers
102 views

How to prevent vents from leaking?

It appears that in my house the cool air from the vents is causing moisture to condense around them and drip down the walls. Is there any way to prevent this? Also, is this in any way potentially ...
Runeaway3's user avatar
  • 193
1 vote
0 answers
159 views

Extra valves on AC lineset?

I'm installing a mini-split system in my shop, but realize I’ll probably need to move the outdoor unit in 6-12 months. Does it make sense to try to add a pair of valves to each line to allow them to ...
Rick's user avatar
  • 525
1 vote
0 answers
54 views

Compatible filter for a Hiyasu HR-24LA HVAC unit?

We bought a house with the A/C installed. We found a lot of dust, and realized that the filter was entirerly missing in the indoor unit. I have found it in the Hiyasu catalog, and I found a manual for ...
Acrofales's user avatar
  • 173
1 vote
0 answers
4k views

Replaced AC Filter and now AC is not turning on

I just changed the filter for my National Comfort model CPG41238-U23 AC unit and now the unit is not turning on. Initially it was turning on but constantly short cycling every 30 seconds. Now the unit ...
Arvisionz's user avatar
1 vote
1 answer
722 views

Should whole house humidifier leak cold air in the summer?

I've recently been learning a lot about sealing our HVAC ducts to improve system efficiency. On my mission to seal every accessible leak, I noticed my air conditioning/furnace cabinet joints were ...
Ocelot20's user avatar
  • 119
1 vote
0 answers
242 views

Any way to reverse engineer split ac inverter compressor speed?

Summer has come and I've got myself an oversized inverter Air Conditioner (1.5 ton for 120sqft room) as suggested by some YouTubers. Details: Outdoor temp day: 43C, Night: 30/35 Relative Humidity: ...
Subrata's user avatar
  • 21
1 vote
0 answers
38 views

Upstairs is getting frigid at night during cool nights

I have a dual zone Lennox system, and it cools well, but for the past few weeks it seems to run away at random cooling the upstairs to several degrees lower than requested. We have EcoBee thermostats ...
Daniel LaRue's user avatar
1 vote
0 answers
2k views

Thermostats with or without variable temperature differential (swing)

I am looking at replacing my thermostat, and don't really need or want one with geosync. I am thinking of the honeywell RTH9585wf. Currently I have a lux that is not wifi but programmable. It ...
Matt's user avatar
  • 51
1 vote
0 answers
92 views

Why is my HVAC system not turning on the A/C compressor?

My AC stop cooling. Here's what I found. Inside blower is working, outside compressor/fan does not turn on. I manually push the contacts in the outside relay and the compressor and fan worked, used ...
Mau Silver's user avatar
1 vote
0 answers
8k views

Carrier Furnace (6-wire) to Honeywell thermostat --> no cooling :-(

Carrier Furnace w/ Honeywell WiFi Thermostat I have a Carrier furnace with the cheapest programmable thermostat (TB-PHP01) that came with my house. The thermostat uses six wires: Y, C, R, G, W, and O. ...
ces's user avatar
  • 11
1 vote
0 answers
133 views

The new AC doesn't cool the house down like old unit, what can be the problem?

I had to replace my old HVAC because it was old and had a freon leak. The new unit doesn't cool down the house like the old system. The ac runs all day and it takes hours to get down to 72 degrees and ...
Sami's user avatar
  • 125
1 vote
0 answers
59 views

Furnace blower cutting in and out during A/C use

Backstory: I fired up my air condition for the first time this season (single family house) and felt lukewarm air coming out of my ducts. When i went outside i saw that the condenser was not turning ...
homediyer's user avatar
1 vote
0 answers
3k views

Does cabling between a mini-split indoor and outdoor unit need conduit?

I am installing a mini-split AC system where there are multiple indoor units connected to a single outdoor unit. For each indoor unit, there is a separate 4-conductor cable that connects to the ...
newothegreat's user avatar
1 vote
0 answers
448 views

Controlling one FCU with two thermostats

I have a chilled water fan coil unit that will feed two areas, living and the bedroom. I want to control the FCU with two thermostats, one in the living and one in the bedroom, (preferably) in a ...
SMA's user avatar
  • 11
1 vote
0 answers
15k views

Carrier Infinity System says "System Malfunction"

On this, the day temperatures reached 95, my AC stopped working. Here are the symptoms: The thermostat says "Infinity System - System Malfunction Call Technician". The condenser outside is spinning, ...
Wynne's user avatar
  • 1,541
1 vote
0 answers
210 views

What is the max MERV or MPR air filter that a 13 SEER HVAC can handle?

I want to determine the maximum MPR (or MERV) rating that our HVAC/furnace can safely handle. We have allergic rhinitis that worsened after moving to this high-pollution, dusty city. There is ...
DoctorWhom's user avatar
1 vote
0 answers
4k views

How would I install a window AC on an awning window?

My house I'm renting was unfortunately made with awning windows. The window I want to place a window AC is a single pane large awning window that winds out. I certainly do not want to go with a ...
dwightmann's user avatar
1 vote
0 answers
78 views

Is this wood the source of the odor?

I moved into a 425 sq ft apartment about a month ago. The AC had a leak for awhile. When I found it, they replaced the AC. I have had the new AC for about 2 weeks. I have a musky old wood odor in my ...
dman's user avatar
  • 283
1 vote
0 answers
2k views

AC Can't keep up with Set Point

After looking here A/C not keeping up and also here Air Conditioner Can't Keep up . I have decided to ask a question that perhaps someone can provide me with more insight. My AC unit was doing ...
Ken's user avatar
  • 5,413
1 vote
0 answers
61 views

Sun control film selection or my bedroom to reduce AC heat load

I have a West facing room with large glass windows (approx. 30 sq ft) in a tropical nation. The summer sun heats up the room considerably. I was thinking of applying sun control film to the windows ...
curious_cat's user avatar
1 vote
0 answers
2k views

Replaced HVAC Transformer, still have no output voltage

My HVAC stopped working, no matter what state the thermostat is in there is no fan, no compressor, no heat, etc. Using a multimeter, I found that the output voltage on the transformer was 0V. ...
DavGarcia's user avatar
  • 263
1 vote
0 answers
1k views

AC fan and Compressor not cycling properly and turning off

AC was not cooling and out side unit fan was turing on intermittently, install the new capicitor, problem stays same, fan and compressor ran, fan stop befor ecompressor, compressor run little longer ...
Hamid's user avatar
  • 11
1 vote
0 answers
3k views

AC capacitor testing with multimeter

When running through my check list to start the AC for the spring/summer I noticed the outdoor fan was not running, hence no cooling. I'm using a basic digital multimeter to test a capacitor with the ...
buck's dad's user avatar
1 vote
0 answers
112 views

Proper A/C BTUs for Apartment

According to this energystar.gov chart, the proper air conditioning BTU capacity for a 500 square foot room is 12,000 BTUs. However, since this is an apartment divided up into several rooms with the ...
fire_water's user avatar
1 vote
0 answers
65 views

How to connect 4 fan coils with one wall control thermostat?

I have 4 fan coils (Sabiana sk-22)and I want to connect them with one wall control thermostat. How can I do?
Nima's user avatar
  • 11
1 vote
0 answers
43 views

Re-locating a split system A/C to a different room

I currently have a split system A/C unit in our living room that is really too small for the room. It runs full blast when it's turned on and whilst it does work at cooling the room, it's not ...
Mark Henderson's user avatar
1 vote
0 answers
87 views

How do I maximize light gain and minimize heat gain for my glass wall?

How to get maximum benefit of daylight while optimizing air-conditioner benefit for a glass wall (currently) of size 11' * 8' (total 88 square feet exposed). Facts: The glass wall never gets direct ...
Optimight's user avatar
  • 187
1 vote
0 answers
125 views

Why doesn't my A/C get power when using the alternate C-wire thermostat hook-up method?

I changed my old Honeywell thermostat for a new Honeywell WiFi thermostat. I installed it just as the directions stated. I used the alternate C-wire method as the old unit did not have one. ...
user13203's user avatar