underrated chiller ???

[piglet]

Forward from bro cookiemunster statements>>>>

QUOTE (Tanggy @ Aug 8 2004, 03:54 AM)

the 1/3 shouldnt be a problem. i tried both the 1/3 and 1/2 on my 5ft. i am using 2x250mh & 2x54watt t5 antinic on a 5x2x2.5 with a 3.5x1.5x1.5 sump. the 1/3 took just over 1 hr to cool by 1 deg and i set it to 24.5. i settle for the 1/2 hp cos it only took 1/2 hour to cool by 1 deg and drop the temp below 25 with ease. I didnt choose the 1/3 cos it was only a slight improvement from my 1/2hp techo and i wanted big in case i upgrade tank or change to 400watt lighting

Bro no offense but I find your results not at all possible.

A 1/3hp chiller manages to cool 1degree in a 5ft tank with 3ft sump in just 1hr?

Can you verify your ambient room temp, whether you are using alot of fans and whether the 1 degree is measured in the tank or from the thermostat reading of the chiller itself? I would say this is only possible for a tank in an aircon room.

I just want to highlight that you need to measure your tank temp for accurate measurement readings. And not read off from the thermostat of the chiller.

For example, many chillers use a small heat exchanger which stores very little volume of tank water at each time. As such this volume is easily cooled down very fast. But similarly heats up very fast too after the chiller cuts out.

Bawater was using a certain chiller brand (which I won't reveal here but its not daeil) which managed to cool his tank from 30 to 26 in just 40mins, and then cutoff. But after 15mins it would cut in again because the temp raised back to 30 very quickly. He suspected it was a faulty thermostat so asked me to change it for him. But even after changing to a new more accurate thermostat with 2 dec places, he still had this problem.

Upon further investigation, I realised it was due to the extremely small size of the heat exchanger (where water enters and exits and where the cooling coils are). Using too slow a chiller pump and because the inlet and outlet was very small, the flowrate was forced to be greatly reduced. Hence it gave a misconception that the tank was cooling very fast and the chiller was super efficient.

But when he used a good thermometer to monitor his tank temp, he found the temp had hardly moved a degree.

Do not misunderstand I am not saying any brand is good or bad here. I am just stating facts to prevent any misconceptions about the true power of chillers.

Its all a matter of thermodynamics. The performance of any chiller can be increased with better design but still it lies in a limited bandwidth for that horsepower.

Theres just no way a 1/3hp chiller can ever cool down a 5ft with 3ft sump tank using 2x250W mh lights. 1/2hp yes but will still run for about 5hrs at best unless the ambient temp of the room is very close to the set temp.

Many reefers have been buying under rated chillers because of this misconception thinking smaller the better and less cost. End up they regret and are forced to sell, resulting in loss of more money. I have a few friends who insisted the small chillers they use are effective and can chill down their tanks effectively. But later during the hot months, it starts to fail due to overwork and stress and never able to bring the temp down to the set point.

If you need to get a chiller, make sure you get 1 which is suited for your tank volume and heat gain needs. Otherwise, its better to just use alot of fans.

I am not trying to pull down or promote any brand. But I do not want reefers to be misled or have a wrong misconception about choosing the correct rated chiller to match their tank needs.

[piglet]

After reading this.... Headache !!!!! ......

Haha, any reefer can advice me on chiller (low energy consumption) for a tank size of 4ftx2.5ftx2.5ft with 3ftx1.5ftx1.5ft sump. Pls help me!!!!!

One thing i want to state is that the watt on the compressor is not the final energy consumption!!! Must include the coil fan watt etc. Thus eg: even arctic / daeil should consume more than 250watt. !!

A bigger hp compressor may require a larger coil and stronger coil fan!! Given a bigger hp compressor but with same coil and fan. >> Will defeat the purpose of larger hp compressor!!!! Further more the size of the small heat exchanger is another important factors to determine the efficiency of the chiller. Not just the hp of the compressor itself!!!!!!!!!!!!!!!!!!!!

Thus larger hp chiller with bigger fan will consume even more energy!!! And we haven't look at the length of the cooling coil. !! Cookie munster has stated a important point for all chiller user to take point, study and comments !!!

For all resun, daeil , arctic and other chiller brand user, let do some discuss on this.... !!!!!!!!!!!!! ( For the benefits of all reefer !!! )

[lvcap]

My personal experience with my 1/3Hp:

1/2 hrs to cool down with my T5 on..

then can rest for 1 hr - 1.5 hr before working..

i guess u guys can read the equipment off my signature below..so dun need to type...

[Tigger]

Using Resun CL650.

When my 2x150Watt kicks in, i find that it take abt 1 hours to chill to 26C, rest for 2 hours or so and start kick in again for an hours or so. Using Extrema to power the chiller

Tank is 4x2x2 with 2.5 x 1.5 x1.5 feet sump tank. Return is ehiem 1262, 1x aquabee pump for my skimmer and 1x 6060 wave maker. So far satisfied with the chiller.

[dr evil]

just to share on my chiller performance. im using a RR1.25hp n my tank is @ 900 ltrs. my tank size is 4x2.5x2.5ft with a 3x1.5x1.5ft sump. my lighting is 2x250watts with 4 x 24watts actinic suppliments.

my tank is set to 25deg and the chiller is located beside by tank. so, the ambience is good.

when the full lighting is on, it will take 3 hrs to cool to 2deg. if no lights, it will take @ 2 hrs.

im actually happy with the performance.

im also looking into building my own chiller. im looking to upgrade to a true 1hp compressor chiller. currently sourcing for a housing.

my 2 cents worth.....

[lightningstrike]

just to share on my chiller performance. im using a RR1.25hp n my tank is @ 900 ltrs. my tank size is 4x2.5x2.5ft with a 3x1.5x1.5ft sump. my lighting is 2x250watts with 4 x 24watts actinic suppliments.

my tank is set to 25deg and the chiller is located beside by tank. so, the ambience is good.

when the full lighting is on, it will take 3 hrs to cool to 2deg. if no lights, it will take @ 2 hrs.

im actually happy with the performance.

im also looking into building my own chiller. im looking to upgrade to a true 1hp compressor chiller. currently sourcing for a housing.

my 2 cents worth.....

pls do look me up when u hv plans to build ur own chiller. i m very interested. but will only be available in late dec.

[dr evil]

pls do look me up when u hv plans to build ur own chiller. i m very interested. but will only be available in late dec.

hi bro,

no prob man........by than, i should be running lioa...

cheers

[lightningstrike]

i will miss the fun then. u can look up weisoon. he has plans to build one too.

[piglet]

Reefers,

How can we really measure chillers so as to determine whether is it under rated?

A number of chillers are packed into compact size and their temperature exchange coils are limited to certain length. ( Longer exchange coil length > higher performance.. ? comments)

[weileong]

To measure the real cooling power of a chiller.

Delta-T = Chiller inlet temp (deg F) - Chiller outlet temp (deg F)

BTU = Delta-T x water flow in gph x 8.3

one hp = 12,000 BTU

So you can figure out the rating and no one can bullshit you

pls correct me if I am wrong.

[weisoon]

To measure the real cooling power of a chiller.

Delta-T = Chiller inlet temp (deg F) - Chiller outlet temp (deg F)

BTU = Delta-T x water flow in gph x 8.3

one hp = 12,000 BTU

So you can figure out the rating and no one can bullshit you

pls correct me if I am wrong.

weileong, just want to make sure....

example BTU=9000, Delta=3 degrees

therefore 9000=3xflow(gph)x8.3

flow rate=(9000/3)/8.3

=360 gph?

=approx 1400l/h?

Think it is a bit slow. Always thought that the cooler the water, the higher the required flow.

[IanJ]

My tank is 5ftx2.25x2 with sump. lights 3x250W and 2x54WT5

other heat imputs, return pump Iwaki 55, Ehiem 1060 and 1260 in sump, 5 2000lit+ powerheads and tunze 6080.

Chiller is Pacific cool 0.75hp. The chiller on temp is set to 27 Deg C, cut off temp 24 Deg. No lights on, the chiller running time is about 1 hour, with all lights on chiller runs for some 4 hours or so. It switches back on well within the hour

This setting gives a true 27 Deg chiller on and 26 deg chiller off temperature in the tank.

The controller is reading the heat exchanger temp and not the true tank temp. Immediately the chiller switches off the temp on the contoller rises from the off set temp of 24 deg to 26 deg of the actual tank temp.

This size chiller with the above tank size/heat inputs is i would say the bear min that one can get away with.(having used several other makes before)

[minsmarine]

I believe there would be way that get the tank temp rather than chiller's temp. I read one in thread but can't find now. ( like external temp controller )

Anyone to share pls.

[minsmarine]

To measure the real cooling power of a chiller.

Delta-T = Chiller inlet temp (deg F) - Chiller outlet temp (deg F)

BTU = Delta-T x water flow in gph x 8.3

one hp = 12,000 BTU

So you can figure out the rating and no one can bullshit you

pls correct me if I am wrong.

Can I do reverse calculation.

Let say I want my tank all together ( including Sump bla bla ), is 400L.

Want to cool down from 3C 27.5C to 24.5C ( so it's 81.5F to 75.1F )

Therefore Delta-T is = 6F

My return pump is rated 2,800L/hr so 740G/hr

So I am going for shopping what could be BTU for my chiller,

BTU = Delta-T x water flow in gph x 8.3

BTU = 6 x 740 x 8.3

BTU = 36,852.

So it's I need 3HP chiller to cool down my tank ( 400L ) from 27.5C to 24.5C in 1Hr.

Or

Change return pump 700L/hr so 185G/hr

BTU = Delta-T x water flow in gph x 8.3

BTU = 6 x 185 x 8.3

BTU = 8,283.

So 3/4 HP will cool down in 1 hr.

Seem like water flow make lot of different. So longer time to exchange the heat.

Is that correct ?

[weileong]

You guys misunderstand already.

Delta-T is the different in the temp of the water going into the heat exchanger and coming out of the heat exchanger.

So in short, you use a good thermometer to measure the temp of the water going into the chiller and coming out of the chiller you should get the Delta-T.

To know the actual flow rate of the pump you have to take into account the head lost as well. Best to use a big tank or tub with known volume to roughly calculate it.

[minsmarine]

You guys misunderstand already.

Delta-T is the different in the temp of the water going into the heat exchanger and coming out of the heat exchanger.

So in short, you use a good thermometer to measure the temp of the water going into the chiller and coming out of the chiller you should get the Delta-T.

To know the actual flow rate of the pump you have to take into account the head lost as well. Best to use a big tank or tub with known volume to roughly calculate it.

So than if we want to know how big chiller and pump combination we need to buy, what is the calculation ? And we only know

how much water we have

what is the temp we want to cool down b4 within 1hr

[weileong]

Then you need to know what's the heat input into your water. The chiller should remove heat faster than the input. Quite difficult to calculate actually.

Here's the specs for the dailea/artica 1/2hp commerical unit.

Model: DA-500B

Cooling capacity: 1170W (1hp = 746W so 1170W = 1.56hp )

compressor: 0.5hp

Fan Motor: 16W

weight: 25kg

size: 21"x14"x15"(WXDXH)

My chiller pump after head lost around 2400 l/h (600 gph) and I measuring a Delta-T of around 2 degs C(ard 3.6 deg F)

Which works out to be

3.6 x 600 x 8.3 = 17928 BTU = 1.49 hp.

So the manufacturer's claim is quite accurate

So you want to know how good is your chiller then go measure the Delta-T

[minsmarine]

Don't want to know how good my chiller cause no chiller yet.

But thinking of buying one and considering what could be capacity.

Still could not figure out

[weileong]

specs sheet of the artica commerical unit.

[weileong]

The aquarium chillers.

[IanJ]

I have and have used a temp probe in the tank that by-passes the chiller. It gives a true indication of the tank temp, you need to set the chiller controller on/off temps wider otherwise the chiller switches off before the controller set temp is reached. It is surprising how long the chiller runs when you control the tank temp this way.

Now i have disconnected the controller because i set the chiller on/off temps based on a digital temp test on the tank, so it was easy to correlate the two.

According to the specs/ calculation given on the Artica data sheet, a 0.5hp chiller should easily work for my tank. I have yet to find one that does. Min is 0.75hp, 1.0hp or above would perhaps be better.

[weileong]

There are a few reefers here using the 1/2hp commerical unit and all have no problem cooling down their reef tank. Some of them running 6x2.5x2.5 reef tank.

To solve your problem, you can always put the chiller output directly into your main tank instead of the sump.

[IanJ]

My inlet to the chiller is directly from where the water enters the sum, the exit is about 1cm and flowing directly at the return pump input. The chiller is fed by an seperate pump. My various experiments on feed/return did not show any differences. The biggest difference i find is on the actual flow rate to the chiller, some of the flow rates suggested, in my opinion, are too fast and a good heat exchange does not take place.

On my tank all 0.5 hp chillers i have tried can at best just hold the temp when all lights/pumps are running. 0.75 hp can actually slowly drop the temp. Not gospel, just my experience.

[weileong]

Yours must be a giant tank then

[AlfaRomeo]

Personally, I am using the 1/2hp commercial model with my 1000L water volume. Set temp is at 26.4 the chiller on/off is controlled by IKS. Chiller is powered by md55 and it seems to be capable of cooling my tank well...

3x250W DE and 100W of FL about 4 inches off the water surface too