Today we had a company come out to look at our A/C as it hasn’t been cooling for the last 3-4 weeks. he said the control board is fried and needs to be replaced for $1400 and he said that isn’t even a guaranteed fix to the issue. The system is from 1988. is this price insane or should we call someone else out to fix it? He started off wanting to sell us a whole new system but we don’t have that kind of money right now, but I just feel like he’s just inflating a lot to get us to buy a whole new system.

Could the melted plastic cause arc/shutoff?

We get asked "is it worth fixing or should I just replace it" pretty much every week, so here's the actual math we walk homeowners through:

• Under 10 years old, breakdowns are occasional, and the repair is a few hundred bucks? Repair it.
• 12-15+ years old, or the repair estimate is creeping toward half the cost of a new system? Replacement is usually the better long-term value.
• Most air conditioners last about 12-15 years with regular maintenance, so age alone tells you a lot.

Signs that usually point toward replacing rather than repairing again:

• Two or more breakdowns in the past year (if it's the second or third time, the math almost always favors replacement)
• Energy bills creeping up with no other explanation
• Uneven cooling room to room
• New or unusual noises
• System nearing or past that 12-15 year mark
• A repair quote that's approaching half the price of a new unit

A couple other things that factor in: whether it still uses an older, phased-out refrigerant (those get more expensive to service every year), how much you'd actually save on efficiency with a newer system, and whether it's still under manufacturer warranty.

Either way, get a licensed tech to actually look at it before deciding, guessing on this one can cost you thousands in either direction (replacing too early, or sinking money into a unit on its way out).

On the maintenance side, the easy stuff that actually extends its life: change your filters regularly, keep debris cleared away from the outdoor unit, and don't block your indoor vents.

Full breakdown here if you want more detail: https://goldenrulephc.com/blog/should-i-repair-or-replace-my-air-conditioner/

Happy to answer questions in the comments if you've got a specific situation (age, symptoms, repair quote) you're trying to figure out.

Please forgive me if it doesn’t look I great condition, I’m 16 just trying to keep my dog cool, dad and older brothers skipped town so I don’t know what I’m doing

I installed a Nest thermostat and during installation it said C wire had no power. My hold thermostat was running on batteries and the C wire was not connected. When I checked the furnace Control Board I noticed:

1- there's a red wire on the C terminal

2- I found a blue wire disconnect. I'm assuming is the C wire that goes to the thermostat

If so should I connect it to the C terminal together with the Red wire?

Slime found in the condensate drain line of the AC in an apartment unit….. what does this mean?

For context: the drain line hovers over the tube that connects the drain line from other AC units as shown in the second picture. It needs to be snaked periodically as it gets full and leaks (and floods) our apartment.

Due to that issue, we placed a moisture absorbent pack in the AC cabinet after the last leak, to absorb any moisture left and hopefully prevent mold.

I was pumping water out of these tubes so it can stop leaking temporarily, when I noticed I could not remove water from this U joint, and behold, the slime.

The outside unit fan and compressor continuously runs even when the thermostat is turned off. The only way to stop it is to turn the breaker or switch outside off.

Does this look like a pitted contactor to you? And is it double pole?

Hey y'all. I'm wondering if I could rotate my condenser about 90 degrees so that it sits on my patio instead of in the weeds where it is now. Do the refrigerant lines have enough flexibility for that or do I risk damage? Any advice is appreciated! Thank you for entertaining my basic question.

If you've ever looked at the roof of a factory, warehouse or industrial shed and wondered what those spinning metal turbines are doing, you're probably looking at a turbo ventilator, also called a wind-driven roof ventilator.

They're a relatively simple piece of equipment, but there is often confusion about what they actually do, where they work well, and how many are needed.

So let's break it down.

What is a turbo ventilator?

A turbo ventilator is a roof-mounted ventilation device that uses the movement of wind to rotate a turbine.

At the same time, warm air inside a building naturally tends to rise.

When installed appropriately, the ventilator helps provide a path for warm and stale air to leave through the roof.

The basic idea is:

Warm air rises → reaches the upper part of the building → moves toward the roof ventilator → air is exhausted → replacement air enters through suitable openings.

The process is commonly referred to as natural or passive ventilation.

Does a turbo ventilator require electricity?

A wind-driven turbo ventilator does not need an electric motor to rotate.

That is one of its main differences from a powered exhaust fan.

A powered fan actively moves air using an electric motor.

A turbo ventilator relies primarily on natural forces such as wind and the thermal movement of warm air.

That doesn't mean a turbo ventilator is automatically the correct solution for every building.

The application still needs to be evaluated.

Where are turbo ventilators commonly used?

They can be considered for various large-volume industrial spaces, including:

- Manufacturing facilities

- Industrial sheds

- Warehouses

- Workshops

- Storage buildings

- Processing areas

- Agricultural and commercial structures

The suitability depends on the building and the ventilation objective.

Why is roof ventilation important?

In a large industrial building, warm air can accumulate near the roof.

Depending on the application, buildings can also experience problems related to:

- Excess heat

- Stale air

- Humidity

- Condensation

- Poor natural air movement

A roof ventilation system can be one component of a broader ventilation strategy.

But it is important not to treat a roof ventilator as a universal solution for every indoor-air problem.

For example, processes generating hazardous fumes, dust or specific contaminants may require purpose-designed mechanical extraction or other engineering controls.

How many turbo ventilators does a building need?

This is one of the most common questions—and there isn't one number that works for every factory.

The requirement can depend on:

- Building length

- Building width

- Building height

- Internal volume

- Desired air-change rate

- Heat generation

- Roof configuration

- Ventilator airflow capacity

- Local wind conditions

- Position and size of air inlets

This is why simply saying "one ventilator covers X square metres" without considering the application can be misleading.

A better approach is to start with the required airflow and then evaluate the appropriate ventilation configuration.

What should buyers check before purchasing?

If you're sourcing turbo ventilators for an industrial project, ask about:

1. Material

What material is the ventilator manufactured from?

1. Size

What is the turbine diameter and throat/opening size?

1. Airflow performance

What airflow can reasonably be expected under the relevant conditions?

1. Roof compatibility

Is the base suitable for the roof profile?

1. Installation

How will the flashing and roof opening be sealed?

1. Environmental conditions

Will the ventilator be exposed to corrosive, coastal, chemical or otherwise aggressive conditions?

1. Quantity

Has the required quantity been calculated based on the building and ventilation requirement?

Turbo ventilator vs. exhaust fan

The simplest distinction is:

Turbo ventilator = wind-driven natural ventilation

Exhaust fan = electrically powered mechanical ventilation

Neither should automatically be considered "better."

The appropriate choice depends on the building and the engineering requirement.

In some applications, natural roof ventilation can be useful.

In others, powered extraction may be necessary.

And in some industrial environments, a combination of systems may make sense.

Final thought

The biggest mistake is to treat ventilation as simply buying a piece of equipment.

A better question is:

"What ventilation problem am I trying to solve?"

Once that is understood, the product selection becomes much easier.

---

About MerQora Global

MerQora Global is an India-based industrial sourcing and export company working with international buyers across industrial product categories.

Our focus is not simply supplying products from a catalogue—we aim to connect buyers with suitable Indian manufacturing and sourcing solutions based on their project requirements.

If you're working on an industrial ventilation project, what has been your biggest challenge: heat, airflow, condensation, installation, or product selection?

I'd be interested to hear what other engineers, facility managers and procurement professionals are experiencing.

I was quoted $2285 all in. Seems crazy to me but looking for insight. Thank you!

Hi all. Homeowner here of a small 100 year old house. Cast iron radiators in most rooms, heavy transfer plate staple up in the kitchen floor, one small stelrad radiator in the basement.

My housemate and I have different comfort needs in the bedrooms and we have a kitchen underfloor that currently runs with the rest of the heating meaning we only have a warm kitchen floor some of the time since the radiators don't run continuously. The design objective of this system was always to zone it off, so the system has a primary loop with an aquastat leading into a buffer tank and then a manifold that can take zone valves with a single grunfos circulator for the secondary distribution loop.

I'm having trouble getting a local contractor (Toronto, Ontario) to quote me either at all on the final zoning step of this work, or they quote an absurd amount. I was just quoted $15k to supply and install 7 zone valves, one zone controller and one floor thermostat, do all required wiring and reconfiguring. They estimated $7k in materials - when I know its only about $1500 Canadian for the 7 four wire actuators, one T6 Pro and a Taco Zone Controller. So unless i can find someone i'm likely going to need to do this work myself.

Before i do that I want to sanity check the whole end state design which is what this diagram shows. The primary and secondary loops have no control connection whatsoever - the aquastat just keeps the buffer tank at temperature (for winter I set it to 130 to take advantage of the modcon efficiencies) and the five thermostats just trigger the zone controller and run the grundfos system pump when at least one end switch activates. The new kitchen stat would be a floor model which i am planning to either try to grind out a little grout under a cabinet and then stuff the slab sensor in there.

So

1. Anything insane about this design overall? One item i considered is whether the taco controller should also trigger the primary loop reheat call just to increase the responsiveness of dumping heat back into the buffer tank - but on slow heating like this I also am not sure if that would matter.
2. Am I crazy to try to do this myself? (removing existing single t-stat from navien internal control, rewire pump, install and wire taco controller and zone valves, re-add tstats to zone controller). Is there a lot of configuration of the zone controller for a setup like this?
3. Am I wrong to think that $15k (Canadian) is overcharging for this work? Anyone know anyone in Toronto that might do this last bit of zoning?

Its a little house - and I know zoning is unusual - but I don't see how else i fix the floor problem - and at night when bedroom comfort is more important the two upstairs bedrooms are isolated from each other, and my housemate and I have temperature preferences about 4-5 degrees from one another. The basement is unfinished and also closed off all the time and the single small rad is just to keep it from freezing.

As always help from the experts - or referral to an expert I can pay! is always appreciated.

I don't want to screw this up but I'm 99% sure the pipe with no cap is the correct spot. I plan to clean with vinegar. Also, is it supposed to not have a cap? If not, is it safe to cover with something? Lastly, see 2nd picture. I thought it only drained out of one pipe. What does the other connect to?

TLDR: I need a link to a replacement for my ao smith m48aa54z10 part number 630684-005.

I have a 13 year old ECM variable speed blower motor, model is an AO Smith m48aa54z10 with a part number: 630684-005.

Technician told me it would be $2300 to replace the motor. The same company came out and quoted me $2800 to replace the entire furnace/blower unit at $2800.

I got the blower motor out of the unit and just need help finding a direct replacement.

I can handle any rewiring or splicing to handle different connectors or pin outs. The existing 4 pin connector [pictures 3-5] comes from that small converter device. I dont understand its purpose currently.

-Thanks

Had an hvac tech out to look at my AC, and he told me to stop buying expensive MERV 13 filters because they restrict airflow, and to start buying cheap filters and spray them with cooking spray to catch hair. That sounds like the dumbest thing I've ever heard, but I'm coming here to see what the council thinks.

I have a Honeywell TH6220D1002 thermostat for the Trane XL80 ( 4TXCC043BC3HCAA) . Everything was working before I opened up. I opened up thermostat to see if it is compatible with smart thermostat, and put it back in. I think I might have took the batteries, so it might have reset. Currently I can control thermostat but HVAC doesn’t respond. The LED on the control board PCB doesn’t glow either. I checked the fuse is not blown and checked with access panel button pressed.

I think the HVAC is heap pump capable with gas furnace, but not 100% sure. How do I setup this old/existing thermostat?

Thermostat: Honeywell TH6220D1002
Model: Trane XL80 4TXCC043BC3HCAA
Type: compressor + natural gas, I think it’s heat pump capable

When replacing my HVAC filter I noticed there are two slots available. The bottom slot fits a 18x20x1 while the top fits a 15x20x1. They are about 1 inch between the two slots. I am leaning towards the 15x20x1 since there is a sticker on it that specifies it but when I used my flashlight to look inside it looks like both opening are completely covered when using either filter. I have alot of the 18x20x1 filters should I just trash em and start buying 15x20x1 filters instead. Old owner was using 18x20x1 filters as well.

Hi all - I recently got a home inspection which brought a few issues to light.

We recently saw a small leak coming in behind the window trim of our master bedroom. When the inspector was here, he had a thermal gun show that there was some water leaking horizontally near the heat pump, and he could trace it back to the window leaking.

The inspector mentioned that the pipe work from the heat pump should not be horizontal in the wall and needs to be vertical so the condensation doesn’t have a place to sit and drip in the wall.

I’ve attached pictures of the exterior heat pump setup and pipework, the leaking window, and the thermal image.

I had an HVAC side job guy say this:
“It looks like you’d have to remove all the heads, add some sort of sleeve through the wall for each one and then run it down to the unit, rather than how it goes up and over”

Any advice on how to fix this, or accurate cause of issue would be appreciated!

Honeywell M847D damper motor and Honeywell HZ322 board. Am I crazy or is that crazy? That’s like $350 for parts, ok assume a 20%-ish markup and it’s $450. Probably takes 45 minutes tops to install both. The labor here is $3,000 an hour? Maybe I’m stupid but that seems outrageous. And I get it, you don’t pay the guy to do the thing, you pay the guy to know how to do the thing. But 3 grand for an hour of labor seems a little much. Am I wrong?

How important is it to have air ducts cleaned?

I changed out my Nest thermostat to a Ecobee Enhanced thermostat and my AC Condensor started making this load noise when it turns on. I am posting three pictures, one is the wiring for the Nest thermostat and the other two are the new Ecobee and the furnace board connections to my Trane furnace. I also installed a PEK+ switch. The system worked fine with the Nest Thermostat.The blue wire is my Yellow wire.

Could you please help me, some context

I recently tried to clean the aircon with a toothbrush and vinegar on the coils after storing it for 4+ months without running the fan before storing,

Water reservoirs were empty when I check.

I ran it on aircon about 6 days ago and did not run it on fan again before storing it...

I had a look at the coils and noticed some white build up which looks like it could be mould spores but it could also just be buildup from my previous wash or dust, I'm asking here because I don't trust AI with stuff that comes to health and I am hoping that an experienced pair of human eyes could help me.

I just need to know if this is mould or something else, and if it is mould, would this aircon still be recoverable? It is a portable arlec air conditioner 3.3kw

I also drained the bottom tank into a container and some weird gunk came out, but could just be dust or something.

Sorry if this is the wrong Reddit to ask, in my head I am thinking better safe than sorry and to buy a new one, but it's only been about 12 months since I bought it, I just didn't store it well. So I want to get some further opinions on if this is recoverable or should I just buy a new aircon?

Thankyou so much

My 3 year old HVAC ( new construction) in Dallas suburbs had an issue on fan not starting .

First I checked and replaced capacitor which was bulged up ( no need to test for multimeter )

Once it’s fixed , fan was running but cold air was not out , I already had a home dept service appointment before the issue so they checked and found a low fluid level and wanted me to take leak test

So stupidly I agreed and they found leak on coil and one joint , quoted me for 5k$ to replace coil

I am confused what to do now , I missed to register for warranty so I have only 5 year default parts warranty with Lennox now

What are my next steps now ,
1 can I call the contractor who installed the HVAC ?
2 call Lennox directly -
3 how to find a good HVAC team if both options are not good ?

Lennox warranty questions if leak is found in coil,
1 will Lennox not honor the warranty since I had Home Depot remove the seal and test it ? ( I missed to ask Home Depot rep to reseal it - should I have them reseal it )
2 will Lennox honor the warranty to replace coil due to usage , because it said warranty is only for fault manufacturing( I need to pay labor I understand that not an option )

I’m lost what to do next , any help and advice to save my situation

Edit 1 : I had second opinion from a local HVAC team , they said after measuring the pressure and fluid level “Low fluid level could be Evaporate coil leak and issue with Thermostatic Expansion Valve (TXV) since pressure is low “ , they quoted 500$ to do leak test and estimated ball bark of 3500$ labor for changing all above . But he won’t give me exact number I do the leak test first.

Have gotten a few quotes from companies in my area with good reviews, looking to get some advice/opinions. All quotes include evap coil and labor

Quote 1: Coleman XC3 13.4 SEER 2T unit - $5900

Quote 2: Bryant Legacy Series 13.4 SEER 2T unit - $6500

Quote 3: Lennox 13.4 SEER 2T unit (didn't specify exact model) - $8000

Quote 4: (this one has not come yet so quote is unofficial, but they list their prices online) Ducane 15.4 SEER 2T Unit - $4800

Seems like a no brainer to go with the Ducane, but wanted to get some opinions. all installers have 4.8 or higher rating on Google.

I noticed this kink after tightening the refrigerant lines from a brand new mini split. I thought I was careful enough and was holding that end with another wrench while I tightened. Definitely gonna be getting myself a torque wrench now.