Pump efficiency related to temperature?

Sandcruiser · 06-02-09, 04:14 PM

Not sure where to post this- mods, please feel free to move it.

I was thinking about my biggest power drain today and believe that it is the pool pump. It is a 3/4hp ( I think ) pump that runs for about 8 hours every day.

I've backed it down to lower time, but that won't work for much of the year as we have a lot of wind= a lot of dirt/leaves falling into the pool

anyway: regardless of the time it runs, it is enclosed in a concrete room that is about 10ft deep by 3ft wide by 5ft high. Unfortunately, the southwest facing wall is 10-inch concrete and painted black on the outside face. Can't repaint it without pissing off the neighbors.

In the afternoon, that pump room gets HOT. I'm thinking about chipping out some vent holes to cool it down as I assume that the pump will live a longer life with less heat.

My question: Does the pump pull more power when hot? A cash savings from energy use reduction would probably motivate me to start chipping concrete.

Thoughts?

Piwoslaw · 06-03-09, 01:15 AM

Even though the pump room gets hot, I'd think the pump itself stays about the temperature. The pool water flowing through it cools it off, so the pump temp depends mostly on water temperature. But having less extreme temperature variations would be better for the building and anything else in it.

Sandcruiser · 06-03-09, 10:46 AM

I'd say that the water should help cool the bearings, but the motor is air-cooled. It seems to me that 45* C air isn't going to cool it as well as 30* C air would (it will never drop below 30 in there... air temp here is rarely below 26).

But you make a good point that the pump might not care that much about the added heat.

dremd · 11-28-09, 03:43 PM

Pool pumps seem to work ok even though they are black and in the Vegas sun so hot that the PVC pipes melted, so I guess that the life wouldn't be affected.

Now if the room has high humidity corrosion would become an issue.

Biggest gains in pool pump efficiencies can be had in the back pressure department.

More flow with less pressure = GOOD.

Buddy of mine converted to a cartridge filter for this reason. It works, but I don't like pulling it apart to clean it.

There are gains to be had by opening up your jets openings (eyeballs) a little.

There are gains in keeping your filter clean (at expense of filtration . . . )

If you have any air leaks on the intake side flow takes a huge hit (buddy with cartridge filter has a flow meter and visible air in skimmer basket causes a 20% hit in flow.

BTW:Bearings in pool pumps are air cooled (on the ends of the electric motor). the only thing water cooled is the seal which is stone.

06-02-09, 04:14 PM	#1
Sandcruiser Helper EcoRenovator Join Date: Apr 2009 Posts: 33 Thanks: 0 Thanked 0 Times in 0 Posts	Pump efficiency related to temperature? Not sure where to post this- mods, please feel free to move it. I was thinking about my biggest power drain today and believe that it is the pool pump. It is a 3/4hp ( I think ) pump that runs for about 8 hours every day. I've backed it down to lower time, but that won't work for much of the year as we have a lot of wind= a lot of dirt/leaves falling into the pool anyway: regardless of the time it runs, it is enclosed in a concrete room that is about 10ft deep by 3ft wide by 5ft high. Unfortunately, the southwest facing wall is 10-inch concrete and painted black on the outside face. Can't repaint it without pissing off the neighbors. In the afternoon, that pump room gets HOT. I'm thinking about chipping out some vent holes to cool it down as I assume that the pump will live a longer life with less heat. My question: Does the pump pull more power when hot? A cash savings from energy use reduction would probably motivate me to start chipping concrete. Thoughts?

06-03-09, 01:15 AM	#2
Piwoslaw Super Moderator Join Date: May 2009 Location: Warsaw, Poland Posts: 961 Thanks: 188 Thanked 110 Times in 86 Posts	Even though the pump room gets hot, I'd think the pump itself stays about the temperature. The pool water flowing through it cools it off, so the pump temp depends mostly on water temperature. But having less extreme temperature variations would be better for the building and anything else in it.

06-03-09, 10:46 AM	#3
Sandcruiser Helper EcoRenovator Join Date: Apr 2009 Posts: 33 Thanks: 0 Thanked 0 Times in 0 Posts	I'd say that the water should help cool the bearings, but the motor is air-cooled. It seems to me that 45* C air isn't going to cool it as well as 30* C air would (it will never drop below 30 in there... air temp here is rarely below 26). But you make a good point that the pump might not care that much about the added heat.

11-28-09, 03:43 PM	#4
dremd Need More Eco Join Date: Sep 2008 Location: Scott, La Posts: 172 Thanks: 2 Thanked 6 Times in 6 Posts	Pool pumps seem to work ok even though they are black and in the Vegas sun so hot that the PVC pipes melted, so I guess that the life wouldn't be affected. Now if the room has high humidity corrosion would become an issue. Biggest gains in pool pump efficiencies can be had in the back pressure department. More flow with less pressure = GOOD. Buddy of mine converted to a cartridge filter for this reason. It works, but I don't like pulling it apart to clean it. There are gains to be had by opening up your jets openings (eyeballs) a little. There are gains in keeping your filter clean (at expense of filtration . . . ) If you have any air leaks on the intake side flow takes a huge hit (buddy with cartridge filter has a flow meter and visible air in skimmer basket causes a 20% hit in flow. BTW:Bearings in pool pumps are air cooled (on the ends of the electric motor). the only thing water cooled is the seal which is stone.