HVAC/R and Air Conditioning - Why survive SHTF if it gets hot

[WarJams]

I did a few summers of AC work with an uncle when his son decided he'd rather go to college than work for a living. I don't have vast experience, and its been awhile, but I will always emphasize this one thing. If it sounds like common sense, it's because it is, and like most things that are common sense it often times gets totally forgotten, so its always worth repeating:

Change your God damn return air filters!

A lot of AC problems probably wouldn't even become a problem if people would do regular filter changes. Three months of service is probably a good time frame to appraise your filter and see how it's holding up. If your filter is down low to the ground, if you use shit filters, if have a lot of furry pets or kids, if you live in an old dusty dirty house, that shit will get dirty faster, and may have to be changed more frequently. If not, you can probably let it ride a little while longer. But don't let a dirty filter obstruct the airflow, make everything run worse and sound worse, until the poor filter collapses in on itself like a dying star because the system couldn't breath, thus allowing all that shit a straight shot to clog up your blower, shit up your coil, and ruin your day.

And write the current date on the new filter, that way, when you say "oh, I just changed this in spring" but the date says its from 4/Nov/2022, you can realize how dumb you are, and strive to do better.

 

[ObeseScreamingBlackMan]

I stopped doing residential HVAC work a decade ago, and this thread has largely covered the most important stuff, but I'll add a couple more.

1. The best way to keep your indoor equipment clean is to keep your house/basement clean. The best return filter in the universe won't keep your furnace working right if your draft inducer, blower wheel, and burners are clogged with kitty litter dust that infiltrated your cabinet. If your shit's in an attic, RIP. Having an attic floor will help though.
2. There is no manufacturer of 'the best' HVAC equipment. In 2024 ALL of it is garbage. The 'best' equipment is the equipment that has a distributor/supply house 15 minutes from your house.
3. The most complicated and efficient equipment in the world won't do shit for home comfort if your home is a leaky, uninsulated block of swiss cheese. Insulation and air sealing is your friend.
4. Try to find an HVAC company that does actual service. These days, a lot of them are install companies that hire salesmen to do service, and will try to sell you a new unit even if the only thing you need is a capacitor.

 

[Grub]

Try to find an HVAC company that does actual service. These days, a lot of them are install companies that hire salesmen to do service, and will try to sell you a new unit even if the only thing you need is a capacitor.

We don't service anything we didn't install mostly because of liability. As soon as you touch someone's system you become liable for whatever's going on or pretty much anything that goes wrong in their home from then on. My boss has some pretty bad horror stories from customers trying to fleece money or free shit out of him after going to service their system.

One person tried to sue the company because apparently after fixing the ac, somehow that broke their toilet, that was nowhere near the ac and not used by anyone who worked on the ac. But apparently the toilet worked before the ac was fixed and didn't afterwards so it was the company's fault. Shit like that is why we don't do residential service unless it's stuff we put in ourselves.

And with mini splits, unless it's under warranty, it's honestly not worth fixing unless it's just a condenser fan motor. Most of the time it's going to be the control board or the compressor. The compressors on those will die at the slightest hint of a power surge and when they die they usually take the board out with them. By the time you've paid for the parts and the labour to install it you might as well just get a new unit. The labour will probably be cheaper. The pipes and electrical are already there, there's no brazing, no fucking around dismantling the unit or any of that shit.

Just recently had one of those. On the phone with tech support going through the process as the unit was under warranty. Bad control board, they send a new board, the board was cracked on the corner, tried installing it anyway, didn't work, so they send a compressor because the compressor's under warranty still and a second new board, this board was also cracked in the same fucking corner. Swap both out, 4 hours and 2lbs of r410 later, unit still won't run, same error code. The customer's pissed off, my boss is pissed off at the distributor and the manufacturer, finally they send us a new unit.

I went with a 14 year old kid to swap it out. Literally an hour later including a vacuum down below 200 microns, shit's up and running and cooling the customer's bedroom down. A ll the Chinese electronic shit is so much fucking garbage. We've got some old package units we service sometimes for a grow op, those things are slapped together with duct tape and dreams.

The hodgepodge of controllers and timers and other shit running them is confusing and ridiculous. Random expansion valves, compressors and blowers motors just Mickey moused into them whenever one dies. Probably the only thing original in them at this point is the coils. But you know what, they fucking work even though they're abused horribly. Dude really needs to fix his ducting though. He won't listen. We've tried to tell him this is why he keeps burning through fan motors but he argues, so we keep replacing fan motors and his ducting is still garbage, though he did finally increase his supply and return from 14" to 18", but that was after months of going there every other week or so to fix the problems his shitty ducting was causing.

 

[Pretend To Imagine]

You know it’s gonna be a good day when the previous guy left the unit like this.

 

[bigasscigar]

Are those UV disinfection lights legit or just a meme?

 

[Oxyjen]

Is there any sign of North America getting with the program and starting to use mini-splits instead of the extremes of awful ducted air whole house systems and awful rattly shit window units?

The advantages are too numerous - far lower running costs, ability to adjust each room as you want, filter easily accessible and no other maintenance needed. In some places it also makes sense to take advantage of the heat pump heating mode, which is 3 x the efficiency of an electric heater.

 

[DavidS877]

Is there any sign of North America getting with the program and starting to use mini-splits instead of the extremes of awful ducted air while house systems and awful rattly shit window units?

The advantages are too numerous - far lower running costs, ability to adjust each room as you want, filter easily accessible and no other maintenance needed. In some places it also makes sense to take advantage of the heat pump heating mode, which is 3 x the efficiency of an electric heater.

For retrofits they're pretty common. Not sure about new construction, certainly not seeing them on detached houses.

 

[Oxyjen]

For retrofits they're pretty common. Not sure about new construction, certainly not seeing them on detached houses.

How are the conditions if you want to self install? In Europe there’s a good range of (mostly Japanese) models available. The F-gas ones you are supposed to use a licensed installer for obvious reasons.
The R-290 ones, legally you don’t have to, but it’s still advisable to vacuum the lines and leak test after connecting. Anyone competent can do that though.

 

[ObeseScreamingBlackMan]

Is there any sign of North America getting with the program and starting to use mini-splits instead of the extremes of awful ducted air whole house systems and awful rattly shit window units?

The advantages are too numerous - far lower running costs, ability to adjust each room as you want, filter easily accessible and no other maintenance needed. In some places it also makes sense to take advantage of the heat pump heating mode, which is 3 x the efficiency of an electric heater.

Yeah, they're starting to sell off-brand ones at big-box stores. There's a lot of re-badged Mideas and GREEs for sale online too. There's one called Mr. Cool that comes with pre-charged linesets for even easier DIY. I used to work at a Mitsubishi Diamond dealer that really pushed them and Fujitsu and Daikin distributors are pressing for more installs too.

We'll catch up. I'm going to install one next year for a specific room.

 

[DavidS877]

How are the conditions if you want to self install? In Europe there’s a good range of (mostly Japanese) models available. The F-gas ones you are supposed to use a licensed installer for obvious reasons.
The R-290 ones, legally you don’t have to, but it’s still advisable to vacuum the lines and leak test after connecting. Anyone competent can do that though.

There's plenty of models available from companies who will sell equipment, give instructions, info and tools to people doing it themselves. The only thing is in the US all the building codes are enforced on a county by county basis, so I'm sure there are some areas where it's prohibited.

Units such as: https://mrcool.com/diy-4th-generation-multi-zone/

 

[WarJams]

Is there any sign of North America getting with the program and starting to use mini-splits instead of the extremes of awful ducted air whole house systems and awful rattly shit window units?

Seems to be getting more marketing push ever since Daikin stuck their dick into the American industry. I'm seeing them used for man caves, out buildings and garages, or situations where running a duct from the central air system is just not feasible for some reason. But Americans actually value yard space, they usually don't want multiple small condensers all over the place when they could just have one or two big ones out of the way, next to the other big annoying machines like the pool filtration. I don't think they'll ever supplant the central air, as hard as the government tries to fuck up the industry.

And on that subject: What's up with this next new government mandated freon I'm hearing about that's supposedly going to replace R-410A... but it's fucking flammable or something? (Free my nigga R-22. He was a good boi he dindu nuffin'.)

 

[Oxyjen]

But Americans actually value yard space, they usually don't want multiple small condensers all over the place when they could just have one or two big ones out of the way

If you fit these to a whole home, you get the multi-split type, so one outdoor unit for several room units.
I suppose aesthetically the room units are noticeable whereas a grille isn’t, but I’d prefer it overall.

And actually I think you can get concealed room units if you were doing a new build.

 

[Pretend To Imagine]

Is there any sign of North America getting with the program and starting to use mini-splits instead of the extremes of awful ducted air whole house systems and awful rattly shit window units?

The advantages are too numerous - far lower running costs, ability to adjust each room as you want, filter easily accessible and no other maintenance needed. In some places it also makes sense to take advantage of the heat pump heating mode, which is 3 x the efficiency of an electric heater.

They are not great for primary units in the south. The humidity removal and air filtration are really poor.

In a multi indoor unit application you will run into higher equipment cost, and higher maintenance costs.

The name brand units are expensive, and the off brand ones may not have parts support.

Generally they are less reliable, and don’t last as long.

Regarding the heat pump mode, that is very common on ducted units already. The drawback to heat pumps is the colder it is outside the less efficient they become.

 

[Pretend To Imagine]

And on that subject: What's up with this next new government mandated freon I'm hearing about that's supposedly going to replace R-410A... but it's fucking flammable or something? (Free my nigga R-22. He was a good boi he dindu nuffin'.)

For comfort cooling R32 and R454B they are slightly more flammable than 410a.

Small commercial refrigerators use R290 (propane), domestic refrigerators use isobutane, both of which are highly flammable but are charge limited to less than 6oz per circuit.

Medium to heavy commercial refrigeration is getting away from R22 and R404A and going to 448A and 449A for the R22 retrofit. There are other gases too, but those are very common.

Ammonia has been used in industrial refrigeration and RV refrigerators. But it is poisonous.

CO2 is also being used but there are challenges to using it where outdoor ambient exceeds 87° F. It runs very high pressures around 200 psi on the low side for -20° F, 400 psi for +20° F, and high side pressures between 1000, and 2000 psi depending on outdoor conditions.

CO2 is also used as a chilled fluid in some applications where you use a traditional refrigerant to keep the C02 around 20° F

 

[FieldPiece]

A question. I may be getting an apprenticeship soon. I've just been doing side jobs for friends and family while waiting for a company to get back to me. Mainly fixing shit like bad wiring, contactors, thermostats, capacitors, motors, and the occasional leak. But haven't done shit with sheet metal/ducts and my school only covered it in the book. For service stuff how often are you gonna be working with sheet metal? Don't want to show up on the first day and look like a total retard.

Also I have the following tools, what are some things you would recommend I get?

-Drill
-Impact driver
-Gauges and hoses
-Screwdriver
-Nut driver
-Tinsnips
-Multimeter
-Wrenches

 

[ObeseScreamingBlackMan]

Wire stripper/crimper

Pliers. All kinds. Regular pliers, linesmans, channelocks, long needlenose, offset 90 needlenose,

Basic 3/8 and 1/4 ratchet/socket set plus extensions.

8, 12, and 24 inch pipe wrenches. I had 3 and 4 footers too but only needed them for occasional boiler bullshit.

Tubing tools. Tube cutter, flaring kit, swaging kit, deburrer, wire brush for tubing.

A good flashlight that runs on the same kind of battery as your drill/screwgun

Precision screwdrivers for control wiring.

Straight and offset refrigerant service wrenches.

1/4 and 5/16 ratcheting wrenches and a ratcheting multibit screwdriver with a flex extension

small wire brushes for cleaning flame sensors

Reciprocating saw

your preferred type of utility knife

jumper wires with alligator clips

tape measure

fan wheel/pulley removal tool

allen keys

drill bits and step bit

magnetic switch depresser


There's probably more but I can't think of it atm.

 

[Pretend To Imagine]

A question. I may be getting an apprenticeship soon. I've just been doing side jobs for friends and family while waiting for a company to get back to me. Mainly fixing shit like bad wiring, contactors, thermostats, capacitors, motors, and the occasional leak. But haven't done shit with sheet metal/ducts and my school only covered it in the book. For service stuff how often are you gonna be working with sheet metal? Don't want to show up on the first day and look like a total retard.

Also I have the following tools, what are some things you would recommend I get?

-Drill
-Impact driver
-Gauges and hoses
-Screwdriver
-Nut driver
-Tinsnips
-Multimeter
-Wrenches

Thermometers to take air temperatures and line temperatures.

 

[ObeseScreamingBlackMan]

Yeah, a digital psychrometer and a clamp thermocouple is the way to go there.

Nowadays you can get apps with the PT charts for every gas ever and you’ll definitely need one.

 

[Pretend To Imagine]

Yeah, a digital psychrometer and a clamp thermocouple is the way to go there.

Nowadays you can get apps with the PT charts for every gas ever and you’ll definitely need one.

Honestly digital gauges are the way to go. I’ve been using them for over a decade at this point.

 

[FieldPiece]

My gauges are digital with clamp thermometers and my meter has a thermometer but I do need one for measuring for deltas. Thanks!