MH Chiller Question

mapes5 · 05/23/2020, 08:45 PM

Hi all,

I recently bought a chiller for the first time since I've been in the hobby. I have two 250W MHs with 2 T-5s, and the tank temp has stayed relatively stable since I've had it, but it does swing a bit (it can be as high as 79.5 when the lights are on, or as low as 77.3 in the middle of the night). I also have two fans in the canopy that do a pretty good job of cooling the tank down, but I bought the chiller so that they wouldn't have to run and evaporate water (also bought it just in case my a/c takes a dump).

The issue I am running into is that the feeder pump for the chiller is obviously in the sump, however, the sump temp can be 2-3 degrees lower than the surface water in the display when the MHs are running; therefore my chiller will not turn on when the display gets heated up by the MHs. I have the outflow tube of the chiller sitting in the same chamber as the feeder pump for the chiller, but i am going to move the outflow so that it feeds directly into the display and doesn't affect the temp reading in the chiller. I am hoping this will solve the problem, but I am wondering if anyone had another solution. I even thought about putting the feeder pump for the chiller into the overflow so that it gets a better read on the display tank's temp, but I'm not sure if that makes sense. Is there any way for the chiller to be linked to the temperature of the display that I haven't already stated in this post? (I do have an apex system for the tank)

Anything helps, and sorry for the long read.

Vinny Kreyling · 05/24/2020, 08:31 AM

I ran mine through the chiller into the tank, off the return pump.
No need for a separate pump.
This way you get a true reading on temp.

Rhodesholar · 05/24/2020, 11:27 AM

Mine is running with the feeder pump in the return chamber of the sump into the chiller and the return from the chiller emptying into the display.

I don't know but this seems to me to be the only way to get a level temperature through out the system from a logic standpoint since the location of the chiller pump is at the end of the circulation loop furthest from the chiller.

So basically the water hitting the chiller pump has had to circulate all the way through the system back to that point.

If that makes sense.

My chiller is fed off it's own pump. I did it that way so I had separate control over the chiller flow and system flow.

I also went that way so that if my main pump were to fail there would still be circulation in the system from the chiller pump.

If the chiller pump fails I would least have several hours before the temp got critically high and hopefully I would catch it before then.

05/23/2020, 08:45 PM	#1
mapes5 Registered Member Join Date: May 2020 Posts: 8	MH Chiller Question Hi all, I recently bought a chiller for the first time since I've been in the hobby. I have two 250W MHs with 2 T-5s, and the tank temp has stayed relatively stable since I've had it, but it does swing a bit (it can be as high as 79.5 when the lights are on, or as low as 77.3 in the middle of the night). I also have two fans in the canopy that do a pretty good job of cooling the tank down, but I bought the chiller so that they wouldn't have to run and evaporate water (also bought it just in case my a/c takes a dump). The issue I am running into is that the feeder pump for the chiller is obviously in the sump, however, the sump temp can be 2-3 degrees lower than the surface water in the display when the MHs are running; therefore my chiller will not turn on when the display gets heated up by the MHs. I have the outflow tube of the chiller sitting in the same chamber as the feeder pump for the chiller, but i am going to move the outflow so that it feeds directly into the display and doesn't affect the temp reading in the chiller. I am hoping this will solve the problem, but I am wondering if anyone had another solution. I even thought about putting the feeder pump for the chiller into the overflow so that it gets a better read on the display tank's temp, but I'm not sure if that makes sense. Is there any way for the chiller to be linked to the temperature of the display that I haven't already stated in this post? (I do have an apex system for the tank) Anything helps, and sorry for the long read.

05/24/2020, 08:31 AM	#2
Vinny Kreyling Registered Member Join Date: Nov 2002 Location: Miller Place, NY Posts: 7,206	I ran mine through the chiller into the tank, off the return pump. No need for a separate pump. This way you get a true reading on temp. __________________ 250 gallon mixed reef, 2 Reefbreeder's Photon V 2, Deepwater BLDC 12, DAS EX-3 Skimmer, MTC mini cal, 2-3/4" Sea Swirls, Aquacontroller & 6 Tunze pumps.

05/24/2020, 11:27 AM	#3
Rhodesholar Registered Member Join Date: Jun 2006 Location: Crivitz Wi Posts: 754	Mine is running with the feeder pump in the return chamber of the sump into the chiller and the return from the chiller emptying into the display. I don't know but this seems to me to be the only way to get a level temperature through out the system from a logic standpoint since the location of the chiller pump is at the end of the circulation loop furthest from the chiller. So basically the water hitting the chiller pump has had to circulate all the way through the system back to that point. If that makes sense. My chiller is fed off it's own pump. I did it that way so I had separate control over the chiller flow and system flow. I also went that way so that if my main pump were to fail there would still be circulation in the system from the chiller pump. If the chiller pump fails I would least have several hours before the temp got critically high and hopefully I would catch it before then.