Replacement options for paragon 8145-20

[duckgunner83]

I am a production manager for a packaged ice company in bend oregon. I did a short experiment with one of my walk in freezers the other day when the outside ambient temperature ranged from 21 degrees F to about 48 degrees F. In the winter time there is very limited product and or usage load to these freezers and i feel that these freezers run much more than they need to with the use of our current paragon timers. The freezer that i tested started out in the morning at about fifteen degrees and over the course of six hours it only rose to 22 degrees. What i would like to find is a timer similar to the 8145-20 that allows me to program extended off times, as well as possibly some input options such as internal temp cancellation of off time and external temp cancellation of runtime. i saw that paragon had some newer digital timers availible anyone have any thoughts or experience with what i am trying to achieve?

[install monkey]

surely the freezer operates on a thermostat ,so in low ambients it wont run as much, the paragon timer is to regulate the frequency of defrosts,either lower the setpoint of the stat or decrease the ammounts of defrosts in 24hrs if adjustable, otherwise fit a digital stat to give you full control of defrost frequency,duration and termination temp,
8145 defrost cycle works like this:
Time initiated, pressure or temperature terminated
Timer is running and relay is OFF. Dial rotates continually.
Terminal 4 has power: Refrigeration compressor/fan is ON.
Trippers on dial switch relay ON, defrost cycle begins.
Terminal 4 has no power. Refrigeration compressor/fan turns OFF.
Terminal 3 has power: Hot gas/ electric heat defrost turns ON.
Temperature-or-pressure switch connects to terminals N - X
When temperature-or-pressure limit switch reaches trip point, it closes contacts to solinoid located inside timer that switches timer relay OFF. Defrost cycle ends.
Timer relay is switched OFF.
Terminal 4 has power. Refrigeration fan turns ON again.
Terminal 3 has no power. Hot gas/ electric heat defrost turns OFF.
1 to 6 cycles per day, minimim 4 hrs between cycles
Back-up timed defrost termination 4 to 110 minutes

[install monkey]

try this PDF]


C:\Manuals-DO NOT TOUCH\RCX100\

www.sensor-systems.com/pdf/thermomax/rcxeng_en.pdf

[duckgunner83]

I have tried adjusting the johnsen controls mechanical thermostat and it doesnt seem to have a great effect on the runtime ie the power bill. i will check out the web address. thank you.

[Toolman]

Forget trying all that just install a Carel with a built in real time clock then you can punch in stop and start temps plus off times for specific times and amounts. http://www.carel.com/carelcom/web/eng/home.jsp

[install monkey]

if you want to save money fit a soft start kit or an inverter on the compressor and maybe low energy light fittings

[savoc]

Carel low temp master cella

[Magoo]

Get a paragon with a pressure reset, not totally time driven defrost controller.

[jgroberson]

Don't forget that many mfgs refer to a defrost period as an oil return period
and the 8145-20 has a termination solenoid that can be wired to a temp or pressure control if it's not being used, You can buy a clock with pressure termination but they are about 3 times higher than an 8145-20

Excessive run time may be an indication of box insulation failure especially when you have an ice operation with possibilities your thawed product is getting into the cooler insulation. I have seen many walk ins torn down that had so much water in them they couldn't be carried by human means and I have added foam to the outside on many boxes to bring down excessive heat gain until replacement could be done.

I had a walk in on R-12 that ran 24hr at +15f. Did a core sample on the panels and she was full of ice. Added 4 inches of foam to the outside and the next service call complaint was "You next to fix that damned freezer because it's -40f in there and my shoes stuck to the floor and so did my bare feet when I walked out of one shoe" The thermostat had been turned all the way down previous and not reset. Long runs and big power bills are not always caused by the compressor and can not be corrected with different controls. Frost on the inside of a ceiling or wall panels is your first indication of water inside and the old fiberglass seems the worst. If so
get out your hole saw and attempt a core sample and I say attempt because if it's solid ice you can't drill through it on a freezer and a cooler wall will be full of water
that runs out on the floor around the failed panels

Good Luck to you and thanks for letting me share with you