Freezing temps reassurance request & knowledge check

[stshields91]

I've just completed my pool build and am a bit over 30 days in. With the help of this community, I have a TFPro test kit I'm proficient with, all my equipment manuals download and read, my pool chemistry as balanced with awesome water clarity. So I owe y'all a big thank you!

I've read most relevant thread about freezing temps and those who survived the deep freeze a few years back, but I still need a bit reassurance with my plans.

The 10day forecast for my area is below with a day of particular worry where temps could be down to near single digits with possible 24hr period below freezing. All my equipment is listed in my signature, and I've attached a pic of my pad.

Pool is a 15X30 with water level spa in one corner with 3 sheer decants water feature in the pool. No separate pump for water feature.

I'm educated on what to do if the power fails and know where all my drain plugs are etc. I'm educated on the Jandy valves and how to set the switch in the off position and manually open the flow valves partially to ensure flow to all pipes. I've tested opening my valves partially but would need my pump running at full RPM to keep what I'd consider enough water flowing through my water feature.

Questing for the experienced:

• With this forecast should I just let freeze protection cover me?
• Will leaving my flow rate set to max on my inline chlorinator be enough to protect it?
• Should I manually, partially open my spa suction and return valves or just leave them alone?
  • Note from the pick that I did insulate those pipes best I could.
• I have a tarp and some insulation for 2021 like freeze but do I need to deploy that here?

It seems like just relying on freeze protection is likely enough but I'm so nervous being new at this!

Thanks in advance for the advice
Scott

 

[ajw22]

Welcome to TFP.

Your daytime temps are above freezing. Let Aqualink freeze protection do its thing. You are unlikely to have a freezing problem.

Read...

The Physics of Freezing and Freeze Protection

Recently, there have been a lot of questions from those living in moderate climates about using automatic freeze protection or running pumps to prevent freezing and what a pool owner should do when temperatures drop so I thought it might be useful to have a thread which dealt with the issue from...

www.troublefreepool.com

 

[mas985]

The lesson learned in the great TX freeze is do not rely upon grid power for freeze protection.

If you have power backup, then I think it is fine to rely on either pump or heat lamp freeze protection. However, I still believe that once you get well over 12 hours of freezing temps, it just makes more sense to drain the pad equipment (for equipment above water level). Safer and uses less energy.

 

[stshields91]

Thanks for both sets of advice! I appreciate the input.

 

[mas985]

One misconception is that water will never freeze if it is moving and this is not true. It just makes it more difficult to freeze (lower temps) and will take much longer.

 

[stshields91]

One misconception is that water will never freeze if it is moving and this is not true. It just makes it more difficult to freeze (lower temps) and will take much longer.

interesting! I love this scientific suff! Thanks for sharing.

 

[generessler]

The good news is that if the pool water is significantly warmer than 32F (even a few degrees), it takes very little flow to protect everything. All the pipes and equipment above the frost line hold maybe 60 gallons. A VS pump running at even very low revs should move ~20 gpm, so that 60 gallons is being replaced every ~3 minutes. Even if the external temp is 0F, there's no way for even 34F water to freeze in that short time.

One gotcha you didn't mention is check valve flappers. For my system with the heater bypass diverter set to 50/50, the check valve doesn't seem to open - so the heater doesn't have any flow - with less than 1300 rpm. I set the pump's freeze protect revs to 1800 for a safety margin. We got through the 4 days of <10F weather around Christmas last year just fine with that setup. The water got to 32F during the final night. There was a skim of ice on the surface in the morning.

We have a house in San Antonio. Two neighbors have pools. They do nothing to prep for freezing (the pump freeze protect is automatic) and have always been fine except for the "great freeze." So as others have said, a few chilly nights are unlikely to cause problems.

 

[stshields91]

The good news is that if the pool water is significantly warmer than 32F (even a few degrees), it takes very little flow to protect everything. All the pipes and equipment above the frost line hold maybe 60 gallons. A VS pump running at even very low revs should move ~20 gpm, so that 60 gallons is being replaced every ~3 minutes. Even if the external temp is 0F, there's no way for even 36F water to freeze in that short time.

One gotcha you didn't mention is check valve flappers. For my system with the heater bypass diverter set to 50/50, the check valve doesn't seem to open - so the heater doesn't have any flow - with less than 1300 rpm. I set the pump's freeze protect revs to 1800 for a safety margin. We got through the 4 days of <10F weather around Christmas last year just fine with that setup. The water got to 32F during the final night. There was a skim of ice on the surface in the morning.

We have a house in San Antonio. Two neighbors have pools. They do nothing to prep for freezing (the pump freeze protect is automatic) and have always been fine except for the "great freeze." So as others have said, a few chilly nights are unlikely to cause problems.

Great context and you did touch on the one thing that makes ne nervous. I have the Jandy Versaflo bypass for my heater. I've read the threads here and the manual. Maual states:

6.3 Occasional Freezing TemperaturesIn areas where there are occasional overnight freezing temperatures, the filter pump is often used to keep water circulating through the pool equipment. Although the heater control is OFF, power to the heater must be left on. The bypass accessory has a feature built into the controller circuit board to sense the ambient air temperature. When the air temperature approaches freezing, the bypass gate closes to keep water circulating through the heat exchanger and avoid freezing. Power to the heater must be left on to allow the circuit board to operate.

So I'm assuming Freeze protection has me covered here too. Anyone out there who has the Versaflo valve in a Jandy JXI heater who can share their experiences and plan?

 

[JJ_Tex]

Hey Stshields - I do not have specific experience with your equipment, but generically speaking freeze protection should do the trick for you in our climate. Even in the snowmageddon from a few years ago where we had record lows and were below freezing for several days in a row, people who did not lose power were just fine.

My street was the dividing line between part of the grid that experienced rolling blackouts vs those who had constant power. While I was standing on my raised wall busting up ice and trying to keep my pool alive during our 15-minute blackouts, I could see the 3 pools behind us running away just fine.

My recommendation would be this:
1. Make sure your freeze protection is working correctly and cycling through your pools, spa, pumps to keep the water moving.
2. Have a solid oh crud plan to winterize your equipment in the event of a power outage or equipment failure during a deep freeze, which should include:

• Turning off the breaker to your equipment
• Opening all valves, lids, etc
• Opening all drain plugs including your filter, pump, heater, etc.
• Protect your skimmers from getting cracked by freezing ice (Gizzmo, empty water bottles, cut-up pool noodles, and anything else that will absorb pressure from the ice freezing and expanding)
• Cover your equipment pad with a tarp to retain some heat in there. This is probably the least important step, but easy to do if you have a tarp.

 

[stshields91]

Hey Stshields - I do not have specific experience with your equipment, but generically speaking freeze protection should do the trick for you in our climate. Even in the snowmageddon from a few years ago where we had record lows and were below freezing for several days in a row, people who did not lose power were just fine.

My street was the dividing line between part of the grid that experienced rolling blackouts vs those who had constant power. While I was standing on my raised wall busting up ice and trying to keep my pool alive during our 15-minute blackouts, I could see the 3 pools behind us running away just fine.

My recommendation would be this:
1. Make sure your freeze protection is working correctly and cycling through your pools, spa, pumps to keep the water moving.
2. Have a solid oh crud plan to winterize your equipment in the event of a power outage or equipment failure during a deep freeze, which should include:

• Turning off the breaker to your equipment
• Opening all valves, lids, etc
• Opening all drain plugs including your filter, pump, heater, etc.
• Protect your skimmers from getting cracked by freezing ice (Gizzmo, empty water bottles, cut-up pool noodles, and anything else that will absorb pressure from the ice freezing and expanding)
• Cover your equipment pad with a tarp to retain some heat in there. This is probably the least important step, but easy to do if you have a tarp.

I do have those boxes checked and planned for. So it seems my in-line chlorinator will be just fine too then so I'll stop worrying. I'll just set it's flow rate to max and have faith.

Thanks again for all the reassurance.

 

[stshields91]

With more thinking and seeing the weather forecast firming up it seems (in the DFW Texas area) that we are in for three full days below freezing temps with the lowest of lows being in the single digits. I have my plan set but had a few last questions for everyone here.

• How many leave spa mode in freeze protection vs. opening the spa return valve manually a bit and running off the switch at the valve so the control box doesn't move it?
• I can't stop myself from stressing over the chlorinator. Does anyone take extra precation with that? or does the small amount of water flowing keep it fully protected too?

From all the knowledge shared here, it seems that the only real risk of the spa returns or suction lines freezing to the point of bursting would be if the ice froze complete through the line correct? If the ice freeze in the above ground portion of the pipe but can expand down underground where it won't freeze the risk of busting is greatly reduced right?

I thought though this when I saw a picture of a fiends pool pad and he's never insulated his spa plumbing and never had an issue, even in Feb 2021 deed freeze.

I'm thinking I should just leave spa mode out of freeze protection and let the pump handle everything else. During pool school the builder warned me that have that valve actuating if spa mode were included could lead to a stuck valve and blown fuse on the controller that would shut it down complete.

would love thoughts from the experienced on this?

Pic of equipment pad for reference:

IMG_0316.jpg

• stshields91
• Jan 8, 2024

 

[txgunlover]

DFW here... lived through the 2021 disaster without electricity. As long as you use freeze protection (and it's configured correctly) you'll be fine... this isn't that cold of a cold snap... NOW... without electricity, you need to drain the equipment (pull the plugs) etc.... We put in a generator after 2021, but as long as you have juice... you'll be fine with Freeze Protect.

 

[stshields91]

DFW here... lived through the 2021 disaster without electricity. As long as you use freeze protection (and it's configured correctly) you'll be fine... this isn't that cold of a cold snap... NOW... without electricity, you need to drain the equipment (pull the plugs) etc.... We put in a generator after 2021, but as long as you have juice... you'll be fine with Freeze Protect.

thanks for the feedback. Would you consider have spa mode excluded in a iAqualink system properly configured? That's how the builder left it so I'm assuming so, but some here seem to have it included so the valves are switching between spa and pool mode every 30mins?

 

[txgunlover]

I have spa mode INCLUDED and the valves cycle periodically..

 

[stshields91]

I have spa mode INCLUDED and the valves cycle periodically..

Roger that, thanks for the input.

 

[JJ_Tex]

I have spa mode INCLUDED and the valves cycle periodically..

Me too. Mine switches from pool/spa ruing freeze protection. I personally would let it do that, but if you really want to play around with your valves you can... the key is to make sure each pipe has water running through it. Pipes with water not flowing will freeze and cause damage, regardless of insulation.

 

[stshields91]

Me too. Mine switches from pool/spa ruing freeze protection. I personally would let it do that, but if you really want to play around with your valves you can... the key is to make sure each pipe has water running through it. Pipes with water not flowing will freeze and cause damage, regardless of insulation.

Got it, and does yours cycle every 30mins? I was told by the builder that's the run time for each mode in freeze protect and i cannot be changed, is that correct? This for Jandy iAqualink 3.0

 

[JJ_Tex]

Got it, and does yours cycle every 30mins? I was told by the builder that's the run time for each mode in freeze protect and i cannot be changed, is that correct? This for Jandy iAqualink 3.0

Mine is Pentair and I think it is every 15-20 minutes for me. Sorry, I do not know Jandy equipment, but I'm sure they have some science behind their freeze mode defaults.

 

[stshields91]

Mine is Pentair and I think it is every 15-20 minutes for me. Sorry, I do not know Jandy equipment, but I'm sure they have some science behind their freeze mode defaults.

Roger that. thanks again for all the input and help from this forum!

 

[generessler]

thanks for the feedback. Would you consider have spa mode excluded in a iAqualink system properly configured? That's how the builder left it so I'm assuming so, but some here seem to have it included so the valves are switching between spa and pool mode every 30mins?

I have Aqualink with spill-over spa and haven't used the mode that switches between Spa and Pool every half hour. Seems like Rube Goldberg-ish wear and tear to me: a lot of valve and pump switching (mine shuts down while changing modes). Cracking the spa drain side of the diverter a bit has worked great even with the pump running 1200 rpm and ~38 gpm. When it's balanced the spill-over stops but the spa remains full. With freeze protect @1800 rpm as already mentioned the spill-over trickles, which is nice. So I can just set this up in November and go back to normal in April. nb: I do winterize spa bubbler pump and deck jets with my little shop compressor.