Chiller cycle time !!

Chiller running for a couple of weeks !!Anybody running a 1/4 hp chiller with 180 g tank !! 3/4 pvc pipe, running from sump thru chiller and dumping in top of tank at each end !!Wounder what your cycle time is [on/off] build in thermo. temp range 30*f to 90*f . Setpoint 76*f Mine stays on for 3.5 hrs and shuts off for 3.5 hrs just woundering if this is the norm !! ON-AT 79.6*F
OFF-AT 75.1

 

We are just getting a new system on line and have purchased a 1/3 hp chiller with 1" piping, and the plan is to dump the return water back into the sump to mix with the tank return water. The plan is to have 200g to 210g working volume. Located up in the area of Seattle, Wa, we were told to expect a cycle time of on for < 1h and off for 3 or more depending on the heat input from pumps and lighting.

I grew up in Rockledge Fl, since your south of Miami, I'm "assuming" your running air conditioning in the room with the tank, even still, it is "hot" down there...so I'd expect that a 3 hr run time on a 180g system with a 1/4 hp chiller is in the ball park....

Sorry, but no first hand knowledge....yet....

 

Yea, I am 20 min. from Key Largo !!Thanks 4 responding !!! I keep AC house thermo at 76*f !! Since I installed chiller I turned off the fans , maybe I should keep them running to see if cycle time changes !! Which brings me to another question, should I take water from sump go thru chiller and then back to sump[ like you are doing] or go to tank!!! Also have a little fan on the chiller coils !!! Also runnin 3-175 watt SPS MH !!

 

By running the lines back to the tank at two point then you are just fighting static pressure and making a pump work harder and causing more heat , I would have used siphon from the tank and allow it exit chiller into the sump before I ran piping like you described . But I myself simply would pull from the main pump back to the tank to send water through the chiller then simply run the outlet back into the sump where the water from mixes in its will all hit equilibrium sooner or later as long as the sensor feels heat then it will run the chiller .

And unless you have that chiller setting in another area other then under or next to your then the chiller will simply short cycle all the time , As it removes the heat molecules from the aquarium water then its released from the super heated gas at the condenser coil the cool water will act as a magnet for the heat molecules to go right back into the cooler liquid. Thats what heat molecules do they will rush into a area void of them..

 

Tangster, the chiller has no pump, gravity feed from tank to chiller will not work !!! Chiller rated at 400g to 1000gph !! I thing I need to pump water thru chiller !!

 

So you thing I am just recirculating hot air !!! Chiller is on a stand next to tank !!! not in a cabinet open air !!

 

I thought you meant you had the chiller being pumped from the sump up to the tank on a split line to each corner ?
What do you have the differential set it to kick on at 79 F then it will cut off at say 77 to 78 not sure what control you have or unit type tell me that and I can give you more options . But you have to set the differential and you can not have it located to close to the tank its removing heat from..You are just recycling that heat from chiller over and over eve a 1/4 hp in an ambient temp of 76 should not run 3.5 Hrs and off for the same time.. Something is not set up correctly or you may have to much flow through it , Test the water temp going in and then the water temp leaving chiller to find the temp drop it could be a TXV in need of adjustment or a dirty coil ? Oh and get the amount of gallons or GPH you are pushing through it also I can do the math for you .

I did chiller installs for many many yrs .. Nothing quite as complicated as a 1/4 H.P aquarium chiller simple old building chillers rated in the hundreds of H.P and a 1/4 Hp chiller with a 1000 GPH blasting through it will have little time to extract much heat , The expanded refrigerant gas after it passes the TXV or Capillary tube needs time to extract the heat molecule . I run a 1 Hp and I pass 150 GPH through it mine runs 1 minuet and 45 seconds in a cycle and pulls the temp from 79 to 77 in that amount of time. Mine drops the water temp 3 degree from entry to exit.. and a 1/4 unless its set up properly is just about taxed to the limit at 79F ambient for the temp rise of 150 gals of 78F water . Like a water heater you have to figure temp rise per hr and BTU's of the chiller and then flows and water temp drops and then again where the released heat is being released to as that cause the ambient air to be warmer and then less heat exchange across the coil or heat exchanger barrel .

 

Yea, 3 hrs on and 3 hrs. off something is not right !!! Chiller is 1993 Aquanetics 1/4 hp,667watts 5.8 amps I am running a rio 2500 , at zero ft. 783gph !!gph at 4' my tank 529/2010cm from sump to inlet of chiller from outlet of chiller to a split at each end of tank !! also have my main pump[ Iwaki] 25.8 gpm sucking from sump going thru a SCWD to each side of tank !! Water exiting chiller going into tank 76.4 ,water going into chiller from sump 77.9

 

O.K has the chiller ever been serviced ? its most likely R-12 or maybe R-22 but could be R134a in that yr.. We where going through a lot of federal mandated changes then. Fist off depending on gas type the ambient temps will make a difference and where is the chiller located and how long have you been using it ? has the coil ever been cleaned or unit totally serviced ? Take that 2500 off and slow the flows to about 100 GPH and what is the average room Temp surrounding the chiller ? if you got it use and its a 93 model its could be a issue with low gas and or bad TXV or sludged up cap tube .. and if you got it used ? or have ever turned it up on end or turned it over then the oil and wax may have sludged the coils up on inside. If thats the case then you will have to heat it up and allow the oils to drain back to the crank case of the compressor.. Is the oulet of the condensor coil restricted by a wall or side of the cabinet ?

 

Back in 93 R-12 !!Never been turned up-side down !! I have never serviced unit , only been running chiller for 4 weeks !!Bought used for 150.00. Coils may need cleaning !! Before hooking up to tank set thermo to 35 degrees on chiller and read temp with a hand held probe in a 10 gallon bucket ,temp was 35degrees. I think chiller is alright have a plumbing problem !! I have a ball valve I can restruck the flow down to 100gph !! With 5' head on rio it should only be pumping 529 gph don't think I have the best plumb job, don't know the best way to plumb so compressor is not on for 3 hrs and off for 3 hrs .May try moving chiller futher from tank !! Chiller to the right of tank !!! Avg. room temp 76*f