A421ABD-02C temp and defrost controller

Run through the Penn Johnson A421ABD-02C function and set up.
www.norcalrefrigerationservice.com

[@jeffhall2958]

This controller is very versatile. You can use it as a cooler controller, freezer controller, and a constant cut-in controller easily. For those that do not know what a constant cut-in controller is, you simply mount the sensor in the coil. It monitors the coil temp. When at a given coil temp it turns off, and doesn't cut-in until the coil temp reaches a pre-set temp. This allows the coil to defrost and not turn on until the coil is completely defrosted. It acts just as a Ranco A12-700 or A12-701, with more adjustability. It can also work as a time clock defrost pre-set controller like an eliwell or omnitemp. It's simply a very useful controller. Nice job Dave!

[@brnmcc01]

Yes I've done that before on those pesky small tiny walkins with the "all in one" hard to service package on top of the walkin box. Set the cut out to 27+/- degrees, and cut in to 41 degrees and box temp stays between 36-39! And stick the probe in coil. And no more giant ice monster that's a pain in the butt to thaw out! Ask me how I know... lol many buckets of hot water, and bus pans full of water on the top shelf etc. They use puny cheap coils and 2 3000 rpm tiny plastic fans and not as much coil surface area as a real evap hung from the ceiling. Yes it saves interior space, but it makes cleaning the coils, drain pan, replacing fan motors a real joy.

[@giosource08]

Nice review Dave, I purchased one today (around $70 at united ref. my company 's price) I am working at a huge walk in cooler (customer distribute beer) and they just installed an evap coil with a regular A421, coil totally iced up, customer decided to lower the set point to pass inspection (25F) good thing this controller also comes with a high and low limit as well, will come back tomorrow once the coil is deiced and install this little helper. Great videos Dave, I like your troubleshooting skills.

[@santo101979]

Heads up on the A421 Defrost Controls. If you find that you can only access the OFF parameter, the control is in restricted mode. Double check the Restricted Mode Jumper and make sure it's installed on both pins. Once both pins are shorted with the jumper, you will be able to access all of the menus and parameters.

[@ToxicSeizure]

I’ve been fighting with this thing for months. Thanks for helping me clear some stuff up!

[@HVACRBERT]

been installing a419 for years keep one on truck will upgrade inventory to a421 now thanks for the input great vids bro

[@kingofthecrease30]

they are the best thing for walk in cooler or and medium temp unit that needs defrost. great video 👍

[@surfside11561]

Thank you! Great information. I'm replacing my A419 on my homebrew keezer (chest freezer). I followed your selection of parameters. My A419 is headed to my other freezer.

[@ibiqbal5066]

Great.. been stuck on this one , thanks for explaining it clearly, made it easier to understand installation.

[@aircooledtx]

Nice Thermostat/defrost controller..Dave Penn always made great products.

[@williamloper9260]

Awesome stat with defrost Very Cool! Thanks for walking through it

[@warrensharp935]

Have put on two after watching this, they are working good so far.😎

[@melvincourts5893]

Hey man you really helped a lot. Thank you so much for this video

[@NorCal-refrigeration]

My pleasure

[@squirtlehvac8962]

We need more videos on rack systems. I’m learning on them but i need a lot to learn. 3 years in the field

[@fredflintstone8048]

Penn makes a number of modular inexpensive controllers that are great!

[@davejohnsonnola2758]

Bought one a couple months ago to have on hand. Even with all the various units on this property, still haven't had a good candidate to try it out. Almost put it on a 24" gdm beer cooler the other day for shits & giggles but realized the bartender would probably fiddle with it!

[@Brisket9392]

This can be locked out with the P1 jumper. After you set it move the jumper over then button her up.

[@gregs9555]

Have a true keg cooler, had problems with unit constantly running and icing coil. Took the mechanical thermostat off and replaced it with one of these. So much better, keeps a near constant 37 and no more icing

[@justin0957]

Dave is the controller of temp!!!

[@NorCal-refrigeration]

Justin Hernandez I cool down the hot box

[@repetemyname842]

Nice explanation Dave, thanks.

[@giosource08]

Just an advise the little jumper you mention at 1:49 is to access the menu, today was the second time I found one of these controllers that come with this jumper open from factory. Just set them to bypass and you will get to the menu.

[@NorCal-refrigeration]

giosource08 that's how the come lately.

[@cbcb4946]

Thanks did not have the manuals just made my day earlier thanks great video

[@NorCal-refrigeration]

CB cb glad I could help

[@vinodbadyal3333]

Thank you so much for your help I just couldn't find the dft under advance

[@2010mistersoftee]

Very good thank you I needed that info I have these on my trucks

[@aaronvasquez8612]

Thanks bro 😎 you safe my day !!!

[@chriscooley906]

Been checking out your videos, great content and explanation, I’m digging your positive attitude great stuff Dave

[@NorCal-refrigeration]

Thanks Chris

[@hvacrnortheastern2110]

David if you're going to change over from mechanical thermostat to a A19 electronic thermostat you will need a third wire which is your neutral wire your going have to pull a wire. I been using electronic thermostats for about over 10 years I found out if you get a Emerson electronic thermostat you won't have to pull third wires there a switch on the control for your neutral if your changing from a mechanical thermostat. That's great it a build in defrost they came out with haven't use as yet be great on reach in.

[@alessichris07]

Edward HVACR CT So u can switch from a two wire 120 volt or 220 volt with no wire added with the emerson ,I've had a A19 on my van for a couple years because I don't want to add any new wires to a unit, if its not on the drawing

[@hvacrnortheastern2110]

c alessi WIRINGWiring Instruction NotesSwitch SettingsSwitch SW2 must be set for applications as shown:Line Voltage (Power Stealing)Line Voltage (Non Power Stealing)24 VAC (Non Power Stealing)Power StealingPower Stealing is an electronic design within the control thatcan eliminate the need to connect a neutral line to power thecontrol. The control receives power from the unit it is control-ling. Power Stealing saves time and money by often eliminat-ing the labor to run a neutral wire to the control for power. Seecompatibility chart below for certain limitations. ( Emerson 16e09-101 electronic thermostat )

[@alessichris07]

Edward HVACR CT Got to get one and try it out. Thanks for the heads up.

[@hvacrnortheastern2110]

If your going from mechanical thermostat usual has 2 wire break line voltage to the load your replace A19 electronics thermostat have a neutral going for the control to work correctly so your going have pull wire .l won't go back to mechanical A19 thermostat they use to be good but they aren't made not USA they get out of calibration with all the new refrigerant you get uneven temperature inside the box and the mechanical can't reacted fast enough then your back replacing the thermostat plus electronic you got more control over the temperature cut in/cut out now they come out with defrost which good with all the refrigerant out market.

[@NorCal-refrigeration]

c alessi that's handy

[@UlisesPalacios]

Pretty nice controller. I'm gonna have to try one out.

[@hvacrjunky6119]

Good overview. I haven't used that one yet.😎👍

[@hvacrjunky6119]

65* is that early in the morning??

[@NorCal-refrigeration]

HVAC/R Junky no 7:30 at night.

[@david19226]

Thanks for the explanation, great video. keep up the good work.

[@NorCal-refrigeration]

David K your welcome

[@jmgrefrigeration4000]

Love the review buddy. I am gonna purchase one tomorrow to put on the truck. The only thing is those penn/ Johnson control stats can be duds after 3 months, you notice that? Never really get a ranco dud

[@prophetfgsm]

Great video, installed a couple of those on a 70 Ton walk in (or drive in this case) Cooler, didn't have time to check out the defrost options. Also found on first setup the whole On and Off temps instead of setpoints and differentials got me confused, but once used to it it's much better than the 419's with the jumper to go between heat, cool, start at and stop at setpoint. I get you could use the NC to power the contactor for the heating elements on a freezer but without a klixon I don't think I'd do away from the trusty Paragons yet.

[@NorCal-refrigeration]

Fél ypc this is not for freezers just off cycle only.

[@bowen1969]

great job well explained thanks

[@abdulhvac2395]

Thank you For sharing can you use this for True prep table

[@raulhodge3314]

Off cycle defrost in my opinion is not a good option unless you can program the time of day it shuts the cooling off. For example, the box is already too warm, why (in the first place) would you turn the compressor off and make the box warmer? Especially when the box is in use during business hours and the Health Inspector usually shows up then? I have seen, in my 40 years of correcting bad installs, off cycle timers on many walk in boxes. When the issue was improper sizing or even the superheat adjustment was way too high, starving the coil with decreased cooling capacity. Also if sized properly I set the differential for a minimum of 4 degrees but prefer 5 degrees. If a good refrigeration tech doesn't understand why that is a better method of air defrost then I would like to learn something from them. Not to mention the cycle rate is decreased, thus extending the compressor life. Refrigeration is more logic, reason and common sense than guesswork or hiding the problem to make it seem to go away. P.S. Man I sure miss R-12! LOL! I read different posts on the Internet from all over the world and I have much empathy for some of these guys customers and employers, but hey, glad to see they are seeking important info that advances their knowledge and I just hope their customers aren't paying for their mistakes. Sometimes, I still miss something and have to eat one! Goes with the territory, as they say. Just like the cooks propping the walk in door open for 45 minutes when the delivery truck comes and it's 105 degrees outside! I live in Arizona! Refrigeration guys don't need job security in this neck of the woods!

[@jimbola77]

Excellent video partner thank you for sharing!!!!!

[@NorCal-refrigeration]

jimbola77 your welcome

[@RCG1211]

If a walkin box is equipped with an older style paragon defrost timer how would one hook it up. I am assuming leave in place and remove the defrost set points as this will takeover that function

[@NorCal-refrigeration]

RedCoach Inn that would work.

[@bharatbeerrama6455]

Thank you sir so much need more video about controller please

[@robd760]

How and where do you land your wires for the solenoid to pump it down on a call for off cycle defrost Dave?

[@SHANEO1976]

How do you change from heat and cool mode

[@mkiss879]

I had to replace a419 to a421, long story short kept tripping the breaker with the same wiring provided for 110vac. Luckily I tried the new sensor with the old control (reason why I had to change the control) and it worked, not sure why it kept tripping the breaker though

[@eslns]

Do you need to run a wire to the contractor coil for the defrost feature?

[@asokasl]

Great job

[@carlosemmanuelgarciabrito791]

What's the different between the ABC , BDE and other 421 series ?

[@carlosemmanuelgarciabrito791]

Hey Dave tell me something what's the difference between this one you talking bout and the others 421 series ?

[@NorCal-refrigeration]

Off cycle defrost

[@MrRealtalkME]

Does that control only works for air defrost or can you run it with heaters ?

[@NorCal-refrigeration]

Air defrost

[@Matt-ll1pd]

Looks like a great upgrade. Can it be used inside a walk in freezer?

[@NorCal-refrigeration]

Yes you can!

[@Matt-ll1pd]

Fantastic just ordered one! Thank you!

[@Brisket9392]

@@Matt-ll1pd Just can't use the defrost feature. This is only good for air defrost (off cycle) as it just closes the solenoid. Might as well get the one without it if ordering.

[@Matt-ll1pd]

Thank you

[@lesvegetable3998]

Beer cooler-in with 3 ton Compressors. This temp control, should I jump wire to 240v or 120v.

[@billcv80]

What program are you using to edit ? I remember you said you could do it on your phone...

[@nicolasmartinez1693]

Any actual install videos on this A421ABD? Could this be used for a 12' meat box case?

[@chriswilliams6701]

I have one of these but cannot get into the menus. It is brand new but I can only get into the "off" value.

[@astercai4679]

how often do you need to adjust the control unit?

[@JJj-fo2yz]

So how do I tie this in to an ammonia freezer with hot gas defrost? Need some help please

[@obedb093]

can you install these inside the box? and does the green light stay on all the time?

[@NorCal-refrigeration]

Yes green light is on when there’s a call for cooling.

[@michaelashton515]

Thanks for the info Dave

[@hansfarmer4739]

THank you for the great video! I am working on trying to get this hooked up to a couple fermenters and when I go to hook the sensor wires up inside the controller, I see that the diagram shows a + and a -, but both wires of the sensor look exactly the same to me. Does it make a difference which wire goes in the + and -? Thanks!

[@NorCal-refrigeration]

No

[@glennsepelak5113]

been using 421 that does not have defrost, thanx so much

[@NorCal-refrigeration]

Your welcome Glenn

[@mohammadfarrukhkhan6886]

So this only controls air defrost, cant i set it up for electrical defrost in anyway. I did notice there is a NC and NO option. Is NC for defrost ?

[@Brisket9392]

This is only good for air defrost. Get a Paragon 9145 for freezer.

[@RCG1211]

Excellent video. What are these going for at the supply houses

[@giosource08]

RedCoach Inn got one today for about $70 at united ref (my company's price)

[@fransicoarmenta8461]

Thanks

[@THEtechknight]

So, since this thing only has one relay for shutting the unit off, Where is the defrost relay? Something has to kick the heaters in?

[@throttlebottle5906]

would be for non-heater/convection defrost only or use as thermostat only, leaving defrost cycle to condenser timer.

[@prophetfgsm]

There is a NC and NO contact, you can use the NO for your solenoid/contactor and NF for the contactor on the heater, not ideal without a termination switch for freezer applications

[@throttlebottle5906]

no, that would make it defrost every time the box reached "set temp"

[@NorCal-refrigeration]

THEtechknight for off cycle defrost only.

[@prophetfgsm]

Well god damn you're right

[@timothydelgado4907]

I ran into this yesterday and couldnt figure out how to get into the advanced settings!!

[@NorCal-refrigeration]

Up n down for 5 seconds until you see UN

[@timothydelgado4907]

@@NorCal-refrigeration when your wiring up a 115v drain line heater for a freezer. Does one wire go to N and the other to ground?

[@NorCal-refrigeration]

@@timothydelgado4907 get a dedicated circuit for it.

[@timothydelgado4907]

I’ve been thinking about this all day. To create a circuit I can put one leg to N because that’s always hot, but now I need to think about a neutral. Either I try to tie it in with the evaporator fan or just put my other leg to ground. Kind of like how you would use a cheater cord

[@NorCal-refrigeration]

@@timothydelgado4907 just get a 230 volt heater

[@rtd2348]

does this eliminate the need for timer?

[@NorCal-refrigeration]

Feelin'Myself89 yes.

[@rtd2348]

Nor-Cal Refrigeration & H.V.A.C One less part that can fail 👍

[@jimbola77]

the o'l hooptie van!!!! cool I alway's wanted to have a van!!!

[@marshallm7141]

How would this be used on a freezer?

[@NorCal-refrigeration]

Marshall M only as tstat no defrost from this control. The defrost in this controller is air defrost only. For medium temp.

[@hvactechpr7872]

awesome used the a419... but prolly they won't bring em here

[@bharatbeerrama6455]

Thanks sir 🙏

[@OcRefrig]

Good vid. Looks about the same as the a419 i been using for many years with the addeddefrost feature. Good info here. Thanks.

[@garysmith9772]

Hey do you know what happened to Jim Pittinato inOhio

[@NorCal-refrigeration]

gary smith no I don't. I miss his videos there the best.

[@davejohnsonnola2758]

He is alive and well as of a couple months ago but no longer wants to make videos.

[@garysmith9772]

That's too bad who's going to teach us the difference between right and wrong ways of doing things all the years of knowledge tied up in his head is worth a fortune Jim if you read this please come back

[@jklmnk9596]

Hard working man with a lot of experiance and good sense of humour. I learn a lot from his video's, hope he's doing well and wish him all the best.

[@harrydickson4575]

👍👍👍

[@NorCal-refrigeration]

Harry Dickson 🤘🤘

[@johannebouchard9647]

programmation en francais

[@drcolster]

Hey Dave, you said the other day you have a full time job at a University.. What do you do there.?? Plus you must work 16 hrs a day. SUPER NORCAL DAVE..!! lol

[@NorCal-refrigeration]

drcolster yesterday 5am till 11:30 pm. 😂 I do HVAC both gigs.

[@jimbola77]

hey nor cal how you doing partner no offence on your age partner some people get weird so I gotta watch what I post.

[@abettermousetrap]

These videos are not great. Why isn;t there just a basic user instruction video at the top of a google search rather than all this installing BS and technical crap... DO BETTER

[@NorCal-refrigeration]

Ahhhhh go learn you trade.

[@abettermousetrap]

@@NorCal-refrigeration I do know it but I'm a pharmacist