CL300 cut in every 3 min

[dominik]

Hi, my tank is 3 by 1.5 by 2. I am using CL300 setting the temp at 26 deg using a Dymax 800 as the chiller pump. My tank temp maintain around 25 deg. However since day 1 (Sep 05) my chiller always run around 3 min and rest for 3 min then run again.

My question is my chiller pump not correct? or my chiller got problem?

[firestream]

either the temp probe faulty or you need higher flow rate.

what's the flowrate of dymax ?

[dominik]

800L/H

[Nautical]

based on above information, chiller pump runs at 800 l/hr, chiller runs for three minutes and then rests three minutes.

hypothetically, all things being equal, lets say we change the chiller pump to run at 1,200 l/hr.

then what would be the anticipated run time of the chiller and the rest time of the chiller. i am not asking for speciific timing, but rather should run time of chiller be now longer or shorter. similarly for the rest time - longer or shorter rest time?

your comments please.

[dominik]

i dun know with a 1200l/h pump what the run time will be like. But i feel that a chiller should run something like one hour then rest an hour b4 staring again.

[Nautical]

i dun know with a 1200l/h pump what the run time will be like. But i feel that a chiller should run something like one hour then rest an hour b4 staring again.

i agree with you. chiller should not be cutting in and out so often. will definitely affect life span.

anyone can help with their experience ?

[Clownfish]

use another thermometer to test ur tank temp... dun trust the temp on the display of the chiller...

by the way, use a faster pump... 800 L/h seems too slow... u will not be getting true 800L/H if u minus overheads n manufacturer's overstate... at a slow flow rate, the water in ur chiller cools faster before the relatively warmer water flow in... thus the thermostat on detecting that the water in the chiller is at a low temp, cuts out the supply....

hope u noe wat i mean n i hope it helps

[zephyros]

where is the intake and output of the chiller. R they in the same

sump compartment?

One reason y chiller kicks in so often is that the water intake and output

is in the same sump compartment. very simple reason,

1) chiller kicks in and output chilled water in the same compartment

2) water in compartment cool down very fast

3) chiller stops

4) tank water comes in and raise water temp

5) repeats step (1)

cheers

[framerunner]

Another thing to look out for is the ambient temperature of the chiller. My chiller used to kick in and out very often (10 mins on, 5 mins off) as there is not much circulation of air at the area which is chiller is placed. I managed to solve the problem by placing a small fan to blow out the hot air. My chiller dont kick in as often nowadays

[dominik]

where is the intake and output of the chiller. R they in the same

sump compartment?

One reason y chiller kicks in so often is that the water intake and output

is in the same sump compartment. very simple reason,

1) chiller kicks in and output chilled water in the same compartment

2) water in compartment cool down very fast

3) chiller stops

4) tank water comes in and raise water temp

5) repeats step (1)

cheers

yup all in the same sump compartmen.

Does that mean if i change to higher flowrate it will not change anything?

My main tank is always maintain at ard 25 deg.

[southpaw23]

yup all in the same sump compartmen.

Does that mean if i change to higher flowrate it will not change anything?

My main tank is always maintain at ard 25 deg.

I believe that is your main reason for the constant kickin in and out of the chiller...alot of ppl tend to make the mistake of either putting the chiller output in the same compartment as the input or before the input.

The most ideal situation is to have the output go directly into the main tank...but if that option is unavailable to you, the next best thing to do is to make sure that the input and output or your chiller are in separate compartments with the input being in the initial compartment. That way heated water is taken into the chiller and cooled then released into the next compartment and consequently brought back up to the main tank.

With regards to the pump flowrate. Check what the ideal max and min flowrate is for your chiller and try to keep the pump closer to the max but not exceed the max flowrate. Reason for this is the chiller is rated to chill water at a certain flowrate so the faster the flowrate, the more water gets chilled. Eg, if there is 100 liters of water, a 1000lph pump will likely chill your tank faster than a 500lph pump, provided the pump doesn't exceed the effective max flowrate of the pump.

Things also to note headloss....ie. a 1000lph pump doesn't end up producing 1000lph of flow when taking into account the headloss from the journey to the chiller and also the loss from water travelling through the chiller coils. Tho difficult to calculate actual headloss, it's always safer to go with a slightly higher flowrate pump and worse case, tee off some of the water at before entering the chiller if the pump is too strong...could possibly run an FR from the Tee off...that's what i'm looking to do.

Anyways...hope that helps...

ps...hmmm...think i wrote about this somewhere on another thread...

[Nautical]

i am using a CL650 for my three footer. the pump i use is 1,200 l/h.

cannot recall how many minutes it takes before chiller cuts in and out.

chiller temp sets at 27, and will kick in at 29.

after reading the above, i changed the pump with an increased pump flow rate. the pump is rated at 2,000 l/h but i tuned it down a little, may be to 1,800 l/h.

i have since seen a marked improvement.

it now takes one hour and forty minutes of idling, and when temp reaches 29, the chiller kicks in. however, it takes about the same amount of time to bring the temp down from 29 to 27 before the chiller kicks out again.

overall, like i said, marked improvement.

something to think about, bro dominik, increase the flow rate.

[dominik]

bro Nautical, is your config same as mine (input output in the same compartment)?

Just now went C328 to look for suitable pump, came across a Dymax EPH2000 with 2000L/H at 40 watt costing $22. This pump can be use internal or external wonder anyone using it? Or any other brand and model to recommend (must be low watt and less $$)?

[Nautical]

bro Nautical, is your config same as mine (input output in the same compartment)?

pump is placed in the second compartment of sump tank. this is where the water got pumped into the chiller.

the water from the chiller is then output into the third compartment. try to put the hose near the return pump. in this way, the chilled water got sucked into the return pump fast so that it goes to the main tank asap.

hope it helps.