I learned from someone that pulling out outdoor fan during whole system is running, head pressure should go up , low pressure stays same level for awhile, Txv is good. If low pressure goes up at meantime, telling Txv is bad. Thank you for sharing your knowledge with us.

Low air flow would of made your super heat low,not high.It has the correct amount of refrigerant,look at that sub cool.Let’s see good on charge but superheat is off....What controls superheat?TXV check why it is underfeeding. Even more so low air flow would of made your delta t higher .

Great, great video! thank you so much Josh for taking the time to record in such detail and explain. You’re a very nice and caring person!

Hey man I appreciate how to really explain and how you explain in detail what you do. New tech here and actually learning about txv has been a bit challenging

Thank you so much for your time brother, , you are very kind and caring.

Great Video.....outstanding tip on verification of TXV trouble shooting!

Great service call diagnosis very precise informative and useful...thanks bro 👍👍👍

Thanks for the fundamentals friend!

Definitely TXV it’s slightly restricted, that’s why you have a high subcool when you started to add more refrigerant you have more liquid outside on the liquid line because it can’t get through that TXV kind of backed up. Suctions low like you said and your superheat is slightly high. It’s pretty much starving the evaporator and stimulating sort of like a low on charge that’s also why your delta T is low, not enough refrigerant going through the evaporator.

I like the probes you're using. Cool video.

Note for the official record, you should’ve taken the bulb off in the first place of the TV and put it in a warm bucket of water before adding refrigerant. That would be the simple solution to the problem as well is a timesaver as well.

Good video yeah i agree those txv have a mind of their own lol can’t wait to see the follow up video.. hvac for life lol 🤙🏽

Awesome video! I know I’m super late to the party but I agree the TXV is out of range and should be replaced. The only extra step I would have added is shutting down the system and watching the TXV equalize. Sometimes that will be a dead giveaway.

Great video!

i learned so much in this video. thanks lol

Great explanation

You did good on this. I’m sure people will learn proper techniques from this video. I’ll be a new subscriber. I have videos as well you can learn from.

Thank you b

good video, there was a better way of testing for the txv being bad. without wasting refrigerant. block the condenser and the SH shouldnt change if it does, then you got yourself a bad txv. very informative video. im a new subscriber. keep the videos coming.

Great video

Thanks

Those Fieldpiece wireless probes look nice, but it would be nice if they had bigger temperature clamps.

I also learned a lot thanks the video was 👍

You could also as a precaution check the temperature across your filter dryer. Looks like a small liquid restriction, possibly from someone not purging the system and not brazing with nitrogen causing oxidization that could clog the txv screen, or the filter dryer. Sensing bulb may also not be secured properly or insulated. That said looks like your on the right track.

great info, i heard of putting the txv bulb in hot water not cold.

Great video,,,,i think the TXV ,,non modulating how is should be,,,,!,,,

I have never seen a blower fan capacitor of 40 MFD. Usually 5-10. 40 is like the size of the compressor

Thanks for showing the numbers. Most youtubers don't or will show on a tiny cellphone. Dang, you got nice tools for the job. Maybe some day I will too. What do you think of putting the txv bulb in cold water then hot to see if its adjusting.

you should have a 9/16 wrench for the flare nuts. I’m old school and never use pliers on nut and bolts.

I can see a huge problem on that furnace. The return should came in from both sides of the furnace. With that filter as dirty as it is raises static pressure and lowers CFM and can simulate a bad TXV.

I'm 7 minutes in and screaming that you're super heat is high. How could you have an airflow problem? But i knew you would figure it out

Piston should be charged by superheat . Txv by subcooling. Your delta T is 11 it tells you right away you have a system restriction. Filter dryer, or system contamination or . You must check first if all your mechanic components are clean then see if you have a piston or TXV . You cant charge or measure a TXV system based on superheat it have to be on subcooling.

You know….. This TXV n 410A Have caused more problems n forced homeowners to spend more money…. Pain and frustration. Of course it keeps field technicians busy…but not all technicians have adequate knowledge of how to address n fix it…. Specially in sunbelt area it’s not easy to work in hot 100+ attic. To a point it’s not worth it!

I would've checked airflow first before checking the charge, but that's just me. After all, EAR. E-lectrical A-ir flow R-efrigerant Great video otherwise. Keep 'em coming. 😏

Test txv. Disconnect cond fan and watch to see if txv modulates as it should.

Measure quick is way better for probes you should try it out

Older Lennox furnaces loved to use those big ole 40 mf'ers . Ever since the pulse furnace days. Good diagnosis. 👍

Lennox old furnace with 40 mfd blower cap. Wow never seen it that high.

First, never replace a Capacitor with the one you pull out, that might not be the right one in there. Get the data off the motor tag. Secondly, the superheat is much too high. See if the TXV has an adjustable post, it just might be just a bit of spooge in it. The test with the bulb is to put it in your hand to warm it up, fooling the TXV to feed and then see if the superheat comes down. However, the diagnosis was correct, Weak TXV, …

Just had this problem literally today and same results normal to high subcool high superheat low delta T did a bulb test with the txv and turns out bulb had lost its charge

Looks like the sensing blub is loosing its charge and causing the restriction

What brand of tools are you using

I know I'm late to the video but shouldn't you try the cold/warm water first to try and free it up?

Is it possible to clean a txv? Or do need replacement?

What type of brand is that

You can pull the power wier on the condinsing fan and watch the hi side pressure climb and the suction line pressure will stay the same indicates a bad txv

Look at your suction temp also.. thats a dead giveaway

I've heard those TXV goes out faster

It's wise to discharge the capacitor B4 checking it thanx brainiac out🤔🤪

If you want to know if your txv is working, you need to change conditions. The easiest way is to disconnect the outdoor condenser fan, a properly working txv will keep superheat and suction pressure the same or just a little higher. But if it begins to climb then txv needs replacement.

Could be as simple as bad bulb placement

I guess i wanna ask the chat here if anyone could help me out if thats ok. How does one know which pressures are appropriate? is it like written on the/a general rule of thumb that your suction and head pressures should be or is it some calculations needed. I can just google this but i see so many different answers and methods it gets kinda overwhelming to filter. Thank you

Wow, an hvac video that wasn't recoreded with a potato.

someone explain it to me; i thought with a TXV it tries to hold superheat constant, so why would adding it here result in a change? and how does that help to diagnose a restriction here

I hate residential equipment when the have txvs that are not adjustable. Txv is done bro.

IS THAT A SNAKES RATTLER TO THE RIGHT I AM OUT OF HERE 🐍🐍🐍🐍🐍🐍🐍🐍🐍🐍 😱😱🚑🚑🏥

Can you just change the TXV to a piston an be done with it?

40 mfd for a blower motor. Is it a 110 volts EFM. Cause here 20 mfd is used for 1 HP up to 25 nothing higher than that.,,,,,,,,I kno Lennox Furnace install 40 mfd from Factory

The sound wasn't to clear. Maybe cause of the condenser. I had it full volume still couldn't hear it loud enough.