Can a Chiller be TOO large?

[Keith P]

My setup is a 70G w/ approx 30G sump. I have a large return pump, skimmer, etc. My lighting is 6X39W T5.

I currently have a 1/10HP chiller. My house has thru-wall AC, but not near the hall way where my tank is. To make things worse, my tank is just out side of my kitchen (so it gets hot when we cook).

So far, it's been stable. I have it set for 80, and it never has gone over 81.

I fear when the summer hits, this chiller will be struggling.

Would a 1/3HP be too large? There is a nice one for sale in the WTS forum.

Would a 1/3HP be less efficient?(i.e. cost more to run on the same tank than a 1/10HP)

 

[pecan2phat]

If a chiller's cooling capacity is too large, then you also run the risk of dropping the tank temperature too quickly. Chillers are rated for gradual reduction of temperature. Most 1/3rd HP chillers are at about 4000 BTU cooloing capacity, maybe consider an 1/4 HP model.

 

[Wes]

If you go too large you run the risk of "short cycling". In otherwords, too much on/off which can significantly reduce the life of your equipment.


Sent from my iPhone using Reefs

 

[seldin]

...If you go too large you run the risk of "short cycling". In otherwords, too much on/off which can significantly reduce the life of your equipment. ...

Chiller vendor recommended setting it for a 2 degree range. So mine goes on at 83 degrees and will continue to when the temperature drops to 81 degrees. Then, it will go on again, when temp goes to 83 degrees. Now, for a heater, my set point range is 1 degree, because they can go on and off more frequently.

Here is more feedback on sizing.

I am sure a vendor Chiller guy can answer your questions. Here is what you need to tell him. What will be the hottest temperature the tank will get to. This is the worst case. Also, the size of your tank and sump. So you usually plan for a chiller for the worst case scenario.

For instance, I have a home office where my display tank is located. It can get to 90 degrees in room, because heating and electric is turned off when I am out of room. At the time, the chiller vendor recommended a 1/3hp for my 55 gallon with 15 gallon sump.

That worked fine, when my chiller was in my tank stand and the tank stand doors were open.

Remember, that with a chiller you will need either a built in controller or an external controller. I previously bought a dual stage controller for around $150.

PS. This year, I bought a ReefKeeper Lite controller for my nano tank for $99. I love this thing. It is much cheaper than the external controller and not only does it control my cooling, it controls my lighting, has an extra feature to control not just chiller but also a fan. It is awesome. It is a steal at retail price of $99.

PSS. Please do not get a drop-in chiller ( not plumbed in line) . The drop-in chiller will have a large spring that is a coil that would be placed into the sump. It is bulky, ugly and the inline chiller is a much better performer.

PSSS. You can get great deals on a used chiller in MR and Reef Central, if cost is an issue. I bought mine 4 years ago used. It was an older chiller and it is even older now and works great.

Hope this helps.

 

[batt600]

I have a 1/3 hp chiller on my 75 and works great chiller are rated on you pumps and lighting on your tank. you should be fine

 

[Keith P]

I never thought about short cycling... Makes sense.

I guess I'll just add another fan for evap cooling if things get out of control.

The 1/3HP deal is a really good one, but it's probably too large

 

[pecan2phat]

For reference,
I use an 1/3 HP on about 160g of water volume and it takes about 2 hours to lower the temperature by 2 degrees.

 

[NYreefNoob]

I have a 1/10th on my 80g tank and it keeps up, does run a little longer but temp has never went above the set range

 

[Dre]

Well as you can see every setup is different .My set up is a 90 gal/10gal sump with a 1/4 hp in line chiller in my kitchen.It takes about 30-45 mins. to drop 1 degree in the summer months .I think a 1/4 would be good for you be sure to check the amps.

 

[Keith P]

I think a 1/4 would be good for you be sure to check the amps.

My tank is on a dedicated line/breaker.

Hmm, I guess I can wait for a deal to come around. The 1/3HP in the market is such a good deal tho.

Do you guys think the difference between 1/4 to 1/3 is that great?

 

[Dre]

To be honest sometimes i wish i had a 1/3 hp chiller to cut the running time probably by about 25%.As stated earlier my 1/4 hp run for about 40mins on average to drop the water 1 degree on about 100 gal volume system in my kitchen.I figure if you get a 1/3 hp it would run about 20-25 mins to drop the water 1 degree.I can't tell you to buy or not to buy sorry, but i hope the infomation help you with your decision.

 

[Keith P]

is 20 min considered a short cycle?

 

[Dre]

is 20 min considered a short cycle?

I don't know but remember 20 mins. is an estimate it could run for longer on very hot days which is fine .

 

[seldin]

Reefers that have chillers taking a bit longer to chill.

I have an older chiller that I bought used. I also then have it 4 years. It use to work fine, until last year I converted half of my washing machine closet to half equipment room.

Anyway, what has given my chiller a nice boost in performance is taking the cover off. Sounds minor but it has worked for me. My chiller was bought from a top notch Aquarium service guy and when talking to him, he takes covers off of all his customers chillers for the same reason.

This has worked for me.

Hope this helps.

 

[Keith P]

Good point. Like keeping the dust filter clean.

I've considered upgrading the internal fan. I already have 2 fans around my chiller.
The little corner it is in gets pretty warm.