HVAC Walk-in Freezer 1

[theonemam]

Also I try to stay away from Sporlan and Parker valves, I think they are junk, and I much prefer and trust Alco valves. In all my refrigeration experiences I have came across only 3 bad Alco valves as opposed to 15 bad Sporlan, and 5 bad Parker valves. Alco makes their power heads out of stainless steal. Sporlan does not, and I have seen several heads rust open and loose their charge, thus closing the valve, and causing system restriction.

[theonemam]

Great info here. However I myself would of just replaced the expansion valve as a whole. This looks to be an external equalizing expansion valve, as it has 3 ports, I am suprised to see that it's actually brazed into the lines, most valves in the commercial refrigeration equipment are flare nutted, which in time they loosen and leak freon, I can't begin to tell you how many leaks I have found in these, most of the time it's noted by oil being present in the condensation water.

[Aussieuke]

Not a bad description but a few little hints. The power element can be hard to start on the thread because of the pins.By leaving the superheat assembly screwed in on one or two turns only there is less tension against the element diaphragm by the pins. It also prevents scoring of the diaphragm by the pins. I would not recommend trying to put the element on first and then the superheat adjustment assembly as then you have to try and compress the internal spring ,again messy if slips occur.

[uberdavez]

Thanks for helping this apprentice, Doc..

[DrZarkloff]

@uberdavez Thanks for watching.

[JefferyHunt]

I bet you could wrap bike handle bars with that tape!

[DrZarkloff]

@JefferyHunt You probably could. I don't know how long it would last.

[youngbeechnut78]

Hey Dr. Z., thank's again for an awesome experience through your camera lens! Wish I was there to help you out and learn from you. Hey by any chance would care in maybe making a video or videos on E. P. R. Valves, H. P. R. Valves and C. P. R. Valves?

[7upac]

I cannot believe there is actual "apprentices" or "tradesmen" asking on a bloody youtube video to help out their own real world problems. It's ridiculous. If you can't figure it out yourself you should be fired, or you're in the wrong trade. Actually get out of the trades altogether. Go to university and waste your time for 5 years.

should have put a trolling disclaimer. oops.

[ToledoApplianceGuys]

good video

[ToledoApplianceGuys]

good vid

[ALPHADOG3]

lol, first of all, the "sensing bulb should have been insulated" theirs you first issue. I'd start at it. Please kids, or on call apprentices, never take a TXV apart. The fridge/freezer will cool, simply ask your customer to shut the system off for an  hour every 4 hours till you can get the replacement part.. I love Dr Z, but after you open the system up, the liquid line drier should also be replaced. NO ONE LIKES A CALL BACK!!! Even after 6 mon

[whotaughtyou]

LYNXM.?/tapeSAFECRACKER OUT OF ROLE BY MARTIN KEMP

[kfreezer77]

ccc

[MrBeau0417]

hello dr z im an apprentice in kamloops bc canada i really appreciate your videos and taking the time to explain whats going on ive learnt alot from your vids. Are you familiar with geothermal systems? they are a huge industry where i live. i cant wait for the next walk in box vids. how about reach in coolers as well,or RTUS?keep up the great work you are definately one of my heros!!!

[DrZarkloff]

@MrBeau0417 Thanks for watching.

[ZuffaLtdDanaWhite]

@MrBeau0417 HOO-RAH!! from burnaby BC also :D! Dr. Z's the man. 

[BGreenHVAC]

What steps in your diagnostic led to the discovery of the problem? I have never worked on a walk-in freezer.

thanks

Bill

[DrZarkloff]

@BGreenHVAC The freezer wasn't getting below freezing.

[archeryman5000]

@BGreenHVAC, you will have high super heat, not feeding of all circuits, or not feeding at all.

Most of the time its is however only the powerhead that is bad, or the screen needs cleaned.

jim

[KOKYSU]

Dr. Z I got to the job site and I found the walking freezer's lpc tripped. Its a semihermetic with 404a charged. 20 psig suction and 280 psig head 60 degrees superheat and 20 degrees subcooling, the sightglass is clear no bubbles and i noticed frost from the outlet of the txv towards half way of the evaporator. evap fans are working properly. I think theres a restriction in the txv. I didnt have much time to troubleshoot the txv further but can you tell me if I am aiming at the right direction.

[DrZarkloff]

@KOKYSU It sounds like you could have a plugged up screen at the TXV. If that's not the problem then you might want to check the service valve at the condensing unit for a plugged screen.

[KOKYSU]

Hi Dr. Z If you have to replace a txv in the case a walking freezer, does the stem of the txv has to be adjusted to get the proper subcooling and superheat? or the txv is already preset from factory. thanks

[DrZarkloff]

@KOKYSU The factory presets are usually correct but occasionally you'll need to do some tweaking to get the proper super heat across the evaporator. Freezer evaporators are so easy to flood.

[poland2010]

why is the solenoid valve mounted so close

[poland2010]

you should of just stored the gas in the reciver and leave 1 or 2 psi 

[Prozackityzac]

good video!

[tadaa11]

Did you have to remove the refrigerant?

[DrZarkloff]

@tadaa11 I pumped it down at first then I found other problems that required me to recover the gas.

[54433001]

how did you know that was the problem

[DrZarkloff]

@54433001 The evaporator was stacking refrigerant.

[54433001]

@54433001 i am trying to learn refrigeration don't know what that means.i just bought a book i will look it up.thank you

[NorthernRefrig]

Piece of crap valve put in Q body and sell parts make more money

[death2opposeme]

sweeeeeeeet bout time!!! walkin! woo

[climber3580]

i thought you would just replace the TXV???

[DrZarkloff]

@climber3580 I could have replaced the entire valve. It was easier to just replace the powerhead and the insides of the valve.

[DrZarkloff]

@thereceman There wasn't enough refrigerat flowing through the old TXV.

[good140]

Thanks for taking the time to make this video. Enjoyed and learned.

[bigjoelas]

poland2010-

What do you think the thermostat in 00:09 controls? I'd suggest brushing up on how an Automatic Pumpdown System works. All six of my walk-ins employ the same control system, as well as others.

Furthermore, how can you tell what the proper line size should be without knowing what the coil's BTU rating is or the line length, etc?

I think Zarkloff is one of the better techs out there, definitely NOT a "bad craftsman." Take your negative comments elsewhere.

[phantompenguins]

Dear DR Z i like your videos , I also do some repair work on a/cs and heat pumps,but can you show me how to size in a unit in a house. like showing what to measure,and getting the right CFMs to each room please? Thanks Jason

[cherisong]

What about walk in freezer 2 ?

[poland2010]

your an idiot... why wouldn't you just change the valve ..its better for your labor AND WHY IS THERE A SOLENOID VALVE INSTALLED IN THE COIL... if you installed this refrigeration system... your a very bad craftsmen just like 90% of all other mechanics...... barley making a living....

all mother fuckers using improper size pipes never insulating properly its all right because I MAKE MY WEALTH OF IDIOTS LIKE YOU!

[cherisong]

Your remark is offensive and vile. You have been reported and blocked from replying to me.

[poland2010]

its true

[atlanticforce]

Hi Dr

always enjoying all your video here.

i have a question.how to charge R404a on liquid line? i have seen a compressor with label on it said charge on liquid line only.

there is no service valve on suction line.

thanks Dr.

[DrZarkloff]

Unless you can weigh in the charge then you'll need to put in a schrader valve on the low side.

[fyescas777]

I have a question. Lets say you have a condenser rated at 12,000 btu on an ac unit and you want to replace the evaporator. Do you get an evaporator rated at less than 12,000 btu since the condenser has to be bigger in order to release the extra heat from the compressor or do you just get one that is rated at 12,000 btu as well?

[DrZarkloff]

You're better off getting an evaporator rated for 12,000 btu.

[optmatt]

Hey nice vid,

Just wondering do these txv not have any orifaces or strainers?

[DrZarkloff]

The TXV has a strainer and the TXV is the type of oriface.

[napais]

Thanks for the video

[pclle]

I understand why you had to replace the parts but I am an apprentice looking to know more. Just a suggestion in your videos (I know its a tought job recording all of this and let alone putting it on youtube) but at least for this vid could you present the initial service call, the running characteristics and what led you to believe that the TXV needed to be adjusted? How was the system running? What are the freezer specs? (tonnage, wattage ect.)

[DrZarkloff]

Thanks for the suggestion.

[THEtechknight]

you going to do part 2? it seems unfinished here...

[DrZarkloff]

I'm still waiting for more parts to come in at the parts store.

[PutSome5tankOnIt]

I strictly do residential HVAC, so this was a treat to watch. Props for working one-handed. I can't do it. However, I am clapping with one hand right now. Can ya hear the applause?

[DrZarkloff]

Thanks. I heard you clapping. lol

[chugoneforme]

what was the reason for the rebuild on the valve

[DrZarkloff]

I couldn't adjust it.

[jenko701]

Great job Jim,doing that stuff with one hand is something else.

[DrZarkloff]

Thanks.

[itscool1968]

ok jim now its time to see that new computer:)

and you doing the lawn lol

[V8Jagnut]

good vid. looked like fun.lol

[DrZarkloff]

Thanks

[jefferyb304]

I work at a Kroger store and the walk in freezer probably the size of a chapel at a small church. I think I counted 24 fans one day.

[DrZarkloff]

That sounds like a huge freezer.

[MagicPatrick1]

Discharged heads fail to closed. You sure don't want it stuck open. 1. you get a solid block of ice to thaw out. 2. It will eventually wipe out the compressor.

Sometimes freezers just ice up. Any air leaks introduce moisture. The it freezes and builds and builds and builds.

Defrost termination doesn't sense anything but the coil. (opposite end from txv)

Snow on the ceiling? Look here^

Just don't waste time heating the txv hoping it magically starts working again. =P

[BOOM7233]

Great video

[MagicPatrick1]

Key indications an expansion valve may be bad is excessive flooding of the coil (stuck open) or start pumping down (slammed shut). One major thing to look at before pointing at the txv (thermostatic expansion valve) is the selenoid coil and make sure it magnetized if it's pumping down.

If your lucky, there maybe a schrader between the selenoid body and the txv to verify which is really at fault for that condition. Also, there will be zero changes in superheat by adjusting the txv.

[DrZarkloff]

I had tried to adjust the TXV before rebuilding it. There was no change regardless how I adjusted it. I tried to open it all the way and I even closed it all the way. No change.

[MagicPatrick1]

Jim does his best to display the techniques involved. Yes he skips alot of the in depth lectures, but he's also on the clock.

Some business owners may have just had one of these replaced, and this video would be a great resource tool in understanding thier bill. Lol.

Rigid and other mfg's do make a specialty wrench for powerheads. Boxed end and Cresent wrenches are too wide and get in the way of the body. Channel locks on the head itself  WILL NOT work.

[DrZarkloff]

Thanks. I'll show my power head wrench in the next part. I skipped a little too much this time because it was too difficult to work and hold the camera at the same time.

[67tr876]

the Walk-in Freezer so far looks like it needs a bit of work or not idk ? but nice job

[DrZarkloff]

Thanks. This freezer had been a problem for some time. It was getting down to zero degrees, but the suction line was a solid block of ice all the way back to the compressor.

[67tr876]

i see and zero degrees is bad for the food but i did not know that it could get it down to zero degrees wow my dad say that no ac unit can get down to zero degrees well am now 16

[HvacPro84]

he's right. No ac unit can go to zero. but a freezer can. different refrigerants are used for these aplications. In this case the unit may be running 502a, 404a, or 409c. could even be one that i havn't listed.

[67tr876]

thanks man

[wirejacker]

by the looks of the hole in the ceiling, it has never been sealed....where did all the lagging go from the suction line ? was it a new install ? if it was, why the heck is he using 3/8" elbows...there are things called pipe benders !

the heater tape for the condensate is dangling around in front of the fans. who uses the phrase HVAC slash R !!!!!!

i'm really not sure who this video is aimed at.....if you're a newbie then you get no information and if you're experienced...you just think WTF

[DrZarkloff]

I was making a repair to an old freezer. I had to recaulk the hole because I cut out all of the old armaflex. The armaflex I used has a one inch wall. It's much better than the 3/4 inch stuff that I removed.

[vengencemonger]

How did you know the TXV had to be rebuilt? What symptoms was the system displaying? Would'nt it be easier to replace the entire TXV?

[DrZarkloff]

I was getting frost back to the compressor and no matter how I adjusted the expansion valve, it didn't change a thing.

[diymania]

Sounded like you burped once right before you showed the bulb wrap.

[DrZarkloff]

I might have. I don't remember.

[jasonabrunner]

i think for xmas we need to get you a helmet cam.

[DrZarkloff]

I like that idea.