Freeze protection with VSP pump / priming speed

[InvaderZim]

I upgraded to VSP pumps this past summer and am now programming the freeze protection. I'd just like to confirm that it's safe to run the pumps at a low speed. The goal is to save power and not annoy the neighbors if we have another Texas freeze like last year when they have to run for days on end (although the VSP pumps are much much quieter than before).

Also, the installers set the priming speed lower than the normal operating speed. Does that makes sense? The pumps prime just fine. Is there a rule about priming speed, like as low as will actually prime the pump?

Here are the settings:

Filtration - Min 2450 Max 3295 Priming Speed 2500 Priming Duration 2 minutes
Pool 2850 Spa 2750 Pool Heat 2450 Spa Heat 2450 Freeze Protect 2500
Water Feature - Min 600 Max 3295 Priming Speed 2500 Priming Duration 3 minutes
Speed1 1750 Freeze Protect 2500

The water feature pump runs a waterfall and sprays on top of the pool slide.

Does it seem reasonable to lower the water feature to 1750 or even 600? It's just a loop with the two outlets.

The filter pump min is set at 2450 and I assume there's a reason for that -- maybe the heater or sand filter? I'm not planning on messing with the min setting on that.

 

[Texas Splash]

With the exception of the Feb '21 freeze, we can generally allow pumps to push water at a minimum speed just fine to prevent freeze damage and maintain efficient water circulation for surface skimming. Our freeze spells (normally) aren't too severe. I did notice that the Laars manual listed HERE on page 25 does list some minimum flow rate requirements, so you might want to review those to be safe. But other than that, you can run the VSPs on a low rpm just fine. Anything around 1,200 -1,300 should be fine most of the time. If your waterfall moves fine at 600 rpm, go for it. Maybe once a day ramp the main pump up to about 3,000 for a couple minutes just to purge air out of the system. If the pump(s) prime well on a low rpm, that will work as well. Modify your rpms, monitor, and adjust as needed.

 

[newdude]

+1. And have your backup plan ready before you need it. Consult/download your manuals for any equipment drain plugs and perform a dry run when it’s not an emergency. It doesn’t even have to be a freeze-ma-geddon like last year. It could just be a random car accident that cuts power to your street on a cold night.

 

[InvaderZim]

With the exception of the Feb '21 freeze, we can generally allow pumps to push water at a minimum speed just fine to prevent freeze damage and maintain efficient water circulation for surface skimming. Our freeze spells (normally) aren't too severe. I did notice that the Laars manual listed HERE on page 25 does list some minimum flow rate requirements, so you might want to review those to be safe. But other than that, you can run the VSPs on a low rpm just fine. Anything around 1,200 -1,300 should be fine most of the time. If your waterfall moves fine at 600 rpm, go for it. Maybe once a day ramp the main pump up to about 3,000 for a couple minutes just to purge air out of the system. If the pump(s) prime well on a low rpm, that will work as well. Modify your rpms, monitor, and adjust as needed.

Thanks! I've never run my heater during freeze protect -- it does have a flow sensor that will cut off the gas if there's not enough water moving through it. I know because I had to replace that once in my previous heater. I'll test my pumps at the lower speed to check for air accumulation. I previously had a two-speed pump but it was useless at low speed because the pot would fill with air after an hour or so.

+1. And have your backup plan ready before you need it. Consult/download your manuals for any equipment drain plugs and perform a dry run when it’s not an emergency. It doesn’t even have to be a freeze-ma-geddon like last year. It could just be a random car accident that cuts power to your street on a cold night.

I definitely need to do that -- I see where the plugs are on the filter and pumps and after draining the filter, I wonder if just removing the lids from the pump pots is enough and then covering the equipment pad with tarps. Maybe there's an emergency guide on this site somewhere. Last February, when we hit 4 degrees on the coldest night, I put a tarp over the equipment but we managed to not lose power (critical infrastructure near a water tower), unlike many others in my neighborhood who had massive damage. My Jandy DE filter did crack around the ring although it was facing the wall and I didn't notice it for months, just wondering why the pad was always slightly wet. Those are also back-ordered so I had to switch to a sand filter, which meant rearranging equipment on the pad and moving a gas line to make room. All pretty expensive but it was an opportunity to upgrade the pumps to VSP pumps.

I tried to get bids for a whole-house backup generator last spring and they're all backed up by 6 months and barely return calls. Here's hoping for a mild winter this year so I have another chance to solve this problem before the next big freeze.

 

[wireform]

You don't have to go to the expense of a whole house standby generator to be safe. You can easily get by with a conventional generator that has the tri fuel option or even if it doesn't for $200 you can adapt it to NG and be good. It plugs into an exterior plug which then goes to a sub panel with the circuits you want powered or the regular panel with a interlock mechanism. The only difference is it won't start on its own but it will back up your essential circuits. Vs pumps use low ampsand is very doable.

 

[newdude]

I see where the plugs are on the filter and pumps and after draining the filter

Don’t forget the heater. Those are usually trickier to see but the manual will show you where. Most have 2.

Opening the basket and tarping is a good plan too. A simple work light underneath (not touching the tarp) will probably add a couple of degrees to help further. @Texas Splash has a good pic of what he did.

But definitely do a dry run at your earliest convenience. However it happens it won’t be at a good time and you don’t want to be figuring it out in the pitch dark at 25 degrees.

 

[mknauss]

Preparing Pool for Cooler Months - Further Reading

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