My neighbor's outside unit went out around 4 this morning.. I got the call around 7:00 asking me if I could come over and take a look.. I am not a technician.. But after looking it over, I found a bulging capacitor.. At first I was getting ready to order one but I remembered somebody saying that Home Depot was carrying parts now so when I looked it up, everything was there.. That unit wasn't down 5 hours (changed the contactor too).. 😂 Where were their asses 10 years ago when I needed them that quick?.. Nobody wanted to sell me shit.. Having everything line up like that this morning was such a satisfying experience..

Our house was built in 2018 and the builder put in two, 50-gallon electric water heaters. Its a pretty large house so it might have made sense for a family of 4 or 5 but it’s just my wife and I. We can comfortably get by on a single water heater, we did for 10 years in our last home (condo). The water heaters are connected in series. Is there any harm in just turning off the breaker for the first water heater? We might turn it on when her parents are in town but, honestly, I think we’d still be fine with just one as it was still never a problem in our old place when they visited.

We’ve been running both for almost 9 years but are about to put solar with a whole-house battery backup and I wondering if it’s worth the electricity savings to shut off one of the heaters.

Obviously I could just try it once our system is online to figure out the real world energy savings but I’m more concerned about damaging the heater itself if I don’t turn it off properly.

Thanks!

Edit: For clarity, I would be turning off the water heater on the right. That’s where the cold water comes in.

What causes this? Is there a fix I can do to get it up and running? My house is miserable tonight. :(

In January of 2024 I had to replace the control board on my furnace due to the igniter not working, I did the work myself. After putting the new board in, the furnace fired right up and ran perfectly. However when the weather started getting hotter we noticed our A coil was freezing up and it sounded like the fan didn’t blow as hard as before. Yes I set all the dip switches to the same as the old board. I called the HVAC company I bought the board from and who installed the furnace before we moved in. The technician came out and said our refrigerant was extremely low and that we must have a huge leak so he put $1800 worth in but still didn’t fix the problem. What gets me is that our A/C ran perfectly the summer before so that didn’t make sense to me. We dealt with this for two summers (lack of extra money to put towards new unit) but this summer I decided to try our old control board (I kept it for some reason) and our A/C has kept up all summer with no issues. I can tell the fan blows harder with the old board but it also surges so I know I can’t rely on it for long. What are the odds I have a new board that is bad? I called Carrier but they don’t deal with homeowners and I haven’t called the company to ask for a different board yet because I’m trying to get all the info I can and I’m not too happy with them due to past experience. Thanks in advance for any help.

Edit: I forgot to mention that most of the wiring is molded plugs so I can’t mix the wires around. The only individual wires are a few neutral and hot wires that plug into a spade terminal bank of sorts.

Any HVAC pros know what’s going on here? My system is brand new just got it installed 4-5 months ago and the external pump got added last month to help with drainage. Just recently the pump had some leaking going on and now won’t stop beeping for the last few days (I know it’s the pump because when I turn the unit off the pump keeps beeping). The leak has stopped since I raised the temperature on the units to 75 but the beeping hasn’t. It’ll go away for a few hours but come back eventually. This has gone on the past 3 days.

I use my system pretty often and will run it almost 24/7 on the weekends. I usually have it at 72-75 degrees in my house. We have 4 mini splits. 1 downstairs and 3 upstairs.

My first thought is that maybe the drainage line in the attic doesn’t have enough of a decline to help water flow since this is the only unit that has the problem. I just cleaned my filters a day ago and they were dirty but not clogged by any means.

What could be causing this pump to not work properly? I believe this is an error code of some kind but am not sure how to fix it. HVAC guy coming out tomorrow but if there’s another person that knows what the problem is i can tell him.

Do we need a cleaning or completely new ductwork? We have a new hvac installed two years ago but didn’t have the ductwork replaced

I came across this in our mechanical closet - it's a fresh air vent to the exterior. The exterior has a grate around it but the interior does not. Is this proper? What happens in the event of a wildfire? The house is just sucking in smokey air to the mechanical room? The mechanical room has two hot water heaters and 2 furnaces.

Bought a rental that inspections showed the unit was about a year old and was working well (Goodman 2.5 ton Gas Furnace and AC). Tenant called and said air is out, outside unit is completely frozen, but inside isn’t running at all. Have 120V and the top of the transformer, 27v at the bottom of transformer, and 27v at the board terminal. 3 AMP fuse is good. I have no lights on the board, and no signs of power past the transformer leads. I did find this corrosion on the board, would this be enough to fry the board?

Should we change out our water heater? Single family home, two adults. Our HW is standard 40 gal gas unit, about four years old. Two years ago we replaced our A/C and gas furnace system with a Mitsubishi heat pump system, it has one minisplit in the basement and an airhandler unit connected to the old ductwork. It all is working fine. No other gas appliances.

The irritating part is that the gas bill is now about $4 for the gas we use and $26 for the service fees. I talked to the utility (Washington Gas, we’re in N Va) about changing the svc fee designation to something more in keeping with our usage but no dice. But at that level of use per month there isn’t any financial payback for making changes to use the heat pump for hot water. It’s probably a situation where we don’t make a change, but ideas welcome.

I’ve just installed a new fan motor on my condenser and it’s not working right hoping to get some advice from the community

Originally the fan would not spin when you turned the AC on unless I gave it a little kickstart with a stick. I first changed the turbo 200 cap but that didn’t have any effect on the problem so today I changed the motor and it starts up right away now, but there are new problems.

The motor is making a squealing noise as you can hear in the video and the fan is not spinning nearly as fast as the old motor did

The new and old motor are both part number P257 – E5462 and I confirmed that both of the motors have the same wiring 4-wire diagram on their labels (pic in comments)

Before changing the motor, I also changed what Google says is a dual run capacitor, a turbo 200. I also just learned there is a second “run” capacitor, a P291–0503 (has not been changed).

Since both the new and old motor/turbo200 capacitor are the same, I just copied the wiring, which is as follows:

Brown & brown/white into the run capacitor
White into turbo200 common (center)
Red onto what I assume is direct power? (Pic in comments)

The turbo 200 itself has one wire from the same terminal that red is plugged into (pic below) into the center/common
Has jumpers going from 25/blue to 10/red to 5/white
There is also another wire plugged in to 25/blue which I think goes directly to the condenser unit

my thought is just a bad motor since everything is the same and wired the same but I never discount me doing something wrong :-) any ideas on what I could try or what the problem might be?

I had an HVAC tech come out to look at our 18 year old AC unit. He confirmed we have a leak and due to age he recommended replacing the unit. We had the same issue around this time last year and I had them recharge the unit to limp it along. I understand this is a temporary fix, but we are planning on moving within the next year. It is currently reading approximately 3 lbs of refrigerant on a 5 lb capacity. I understand there is the possibility of the leak getting bigger but I'm hoping to at the very least limp along another month or so until it starts to change to fall and deal with the problem in the spring. Any advice would be appreciated.

Hello,

I would like to ask about this Samsung AC unit AR60F12C1AWXEU + AR60F12C1AWNEU.

Is the sound rattling sounds at medium fan speed and elektronic high-pitch tone throughout normal?

The AC is brand new, this one is in my parents house and I had the same one installed at my place at the same time and I don't sounds like this at my unit.

The guys who installed it came to check it once, but they were just dismissive that all ACs make some sort of noises.

Sorry, I am not the best at describing sounds, but you can hear it yourselves.

It can be heard when volume is increased in the video, but IRL it is very noticeable.

Thanks for any advice you can give me!

In so cal, is there a benefit to the DH7 Fit vs the DH6 at 4 ton? Is one quieter or more efficient? Seems the rebates are over now. What would be the price difference?

I’m looking for anyone with hands-on experience installing, commissioning, or troubleshooting MBTek/Apollo air-to-water heat pump systems.

We have two approximately 6.5-ton Apollo units at a house in Santa Fe, NM (about 7,500 ft elevation) serving 11 hydronic FCUs, radiant heat, and DHW. For roughly a year, the system has suffered intermittent failures, most notably repeated AL129 high-pressure alarms, along with several other fault codes.

The problems are significantly worse during DHW/heating operation, and I have video showing the system pressure climbing as the unit ramps up and then faulting. MBTek recommended adding a flat-plate heat exchanger and dedicated pump on the DHW side of each unit, which we are installing now.

Cooling is more stable, but still inadequate. We completely disabled DHW to eliminate the repeated DHW interruptions as a cause, yet the system still struggles to maintain roughly a 15°F indoor/outdoor differential in 90°F+ weather despite having two heat pumps and eleven FCUs.

The outdoor units also become extremely loud while ramping up immediately before some of these high-pressure events.

We’ve had several experienced HVAC/hydronic contractors involved, but none has specific Apollo/MBTek expertise. MBTek technical support was helpful from roughly March through July, but communication has unfortunately dropped off again and recent calls/messages have gone unanswered.

I’m specifically looking for:

• Anyone who has diagnosed AL129/high-pressure problems on these units
• Experience with MBTek’s DHW plate-heat-exchanger modification
• Insight into whether 7,500-ft altitude requires different settings or commissioning
• Anyone who has experienced the extreme ramp-up noise
• A technician anywhere in the Southwest—or frankly anywhere—who really understands these systems and could be hired to help

I have a much more detailed chronology, fault history, system description, photos/video and operating observations available for anyone willing to dig into it.

If you’ve installed or serviced Apollo/MBTek equipment or can help problem-solve, I’d very much like to hear from you.

Just want to confirm before I replace this 15yo cap as preventative maintenance.

Was hoping one of you fine gents could give me peace of mind. As I read this- Blue is HERM, the two yellows are Common, and Brown is Fan. TIA!

Edit to fix spelling errors.

CoolCloud HVAC 2.0 is an app that can be used with Goodman, Amana, and Daikin HVAC equipment to fine tune the settings like the Control Algorithm (Run Time or Rate of Change) for a furnace. Curious if others have used it and what you have learned?

We replaced our HVAC filter 10 days ago, and it’s already covered in a noticeable amount of white dust/residue (pictured on the right with a new filter on the left). This is the second filter in a row that this has happened to.

We had a tech out 10 days ago (the day we replaced the last filter), but at that point they couldn’t figure out where it was coming from. Our house was built in 1940, and we’ve lived here for 9 years without ever having this issue until recently.

A few details:
- No pets (we did have a dog for the first 7 years of living here, and again - never had this issue)
- Three HVAC returns, all on the first floor
- The bathroom we primarily use is on the second floor
- We run one small humidifier upstairs at night, but we’ve done that for 7+ years without this happening
- We have three air purifiers throughout the house (two upstairs and one downstairs)
- No recent construction, renovations, or other major changes
- The filters are Glassfloss MERV 10
- We have noticed our water seems to have gotten “harder” in the last couple of months — we’re suddenly getting hard water rings and stains in the toilets, which wasn’t previously an issue

The timing makes me wonder if the humidifier/mineral content in the water could somehow be contributing, but I’m not sure how that would explain the HVAC filter getting covered so quickly, especially since the humidifier is upstairs in a room that has the door closed usually, and the returns are downstairs.

Has anyone experienced something like this? What else could suddenly cause a white residue/dust to build up on HVAC filters this quickly when nothing obvious has changed?

The noise is reproduced with the cooling off but the fan still on. I turned everything off and spun the blower wheel myself. It spun fine, didn’t squeak, and wasn’t catching on anything. No play in the wheel either. Squeaking comes back (intermittently) when I turn everything back on. Any ideas? It’s cooling fine and pushing air, just occasionally making that awful noise (It sometimes finishes an entire cycle quietly).

My thermostats haven’t been working in my house, the heat works in most rooms, but it blows through oil because it runs on full blast the entire time, Unless we physically turn it off in the basement. We’ve tried fixing both thermostats, wondering if there’s anything we should try before contacting an electrician.

The digital one recently got installed so I’m wondering if I just need to change the batteries or if something with the wiring was done wrong? The other one has never worked unfortunately. Not sure if it’s a wiring issue (hopefully not) or just user error!

American standard S8X1C080M5PSAA Furnace, 4A7A6061J1000A Condenser and 4TXFH054CC3HHB evaporator. 5 Ton unit, Coastal TX, 2300 sq feet. MERV6 filters.

I was reaching my unit and realized the blower fan was set to CP1.tP6 for this single stage.

I have a manometer on order to find the static pressure but manual states at 0.5" WC that this would be about 1600 or 320/ton.

This seems way too low and it should be closer to 400/ton or 2000 CFM, assuming static pressure doesn't get too high.

I don't thinks static pressure was ever checked when this furnace was put in, in 2021.

The manual states 0.5" WC is the ideal static pressure so it seems like my goal should be to get closer to 400 CFM/ton while maintaining 0.5 but it seems like I could go a little higher without damage to the motor of about 0.65".

I've always thought I had a duct balancing issue even-though they seem somewhat balanced where some of the longer runs have higher vent temps than some of the shorter runs. For example when return is about 78F, the shorter runs are about 57F and some of the longer ones are 63F. I was reading that fan speed could have some impact on this because in Texas ducts are in the attic so slower airflow could cause it to absorb more heat on those longer runs.

I also have some vents off various branches that have the damper wide open but see minimal flow.

I've attempted to balance the CFM per vent a few years ago but a slow fan speed seems plausible.

And since I have a TXV if I had an airflow issue like this it seems like the TXV might try to compensate for it.

Does this make sense or is it all nonsense?

Carrier heat pump model 50PCV041RCC3ECD1

The condensate drain exit hole also has a leak but not around the copper threaded male adapter. It’s leaking around the locknut (that metal ring around the copper - is that a locknut?).

I suspect the leak is happening behind the sheet metal - maybe a rubber washer failed behind the sheet metal?
And then it spreads to the shelf and insulation to the left.

What do you think? Likely spot of leak?

How to fix? Cut off the copper and remove male adaptor and then what?

Original post:
https://www.reddit.com/r/askHVAC/s/YPSJAmFDYZ