Running outdoor inground pool during winter (real winter)

[najetset]

Hello,

I'm wondering how many/who here are running or have run their inground outdoor pool during winter and specifically in parts of the world that see sustained 24 hour/day -20C to -30C (-4F to -22F) ambient temperatures for 3 to 4 months a year?

ie. parts of North Dakota, Montana, Minnesotta, Michigan, Alaska; and most of Canada

 

[mknauss]

There have been a few members on the forum that use a blow up enclosure for the winter and keep it heated inside along with pool being heated. Takes some effort and $$$, but doable.

 

[ajw22]

There have been a few members on the forum that use a blow up enclosure for the winter and keep it heated inside along with pool being heated. Takes some effort and $$$, but doable.

And have backup power and pumps.

I think biggest risk in running pool during winter is power or pump failure.

 

[sktn77a]

Are you taking about using the pool or just keeping the water circulating (ie not winterizing it)?

 

[najetset]

And have backup power and pumps.

I think biggest risk in running pool during winter is power or pump failure.

Good points!

I have a 96kW NG Genset with ATS, so we should be good for power either way.

Perhaps having a 'spare' pump on hand would be prudent, ready to be swapped out if needed.

 

[najetset]

Are you taking about using the pool or just keeping the water circulating (ie not winterizing it)?

Ideally keeping it running to be used.

 

[mknauss]

Read this thread -- Pool Dome in Michigan

 

[ajw22]

Ideally keeping it running to be used.

Condensation from heating cold water mixing with flue gasses will corrode a heater. Most heaters have a minimum operating water temperature. If you are going to run the heater in the winter you have to keep the water temp above around 70F.

 

[najetset]

Read this thread -- Pool Dome in Michigan

That was great reading. I hadn't thought of an inflatable dome. We have a few commercial size ones around town for indoor tennis and golf centres so they can operate during winter. I had thought of of those huge white 'party tents' made of heavy plasticized canvas and vinyl that have a rigid frame system for support and span.

The practical, sensible, conservative part of me says that some sort of structure over and around the pool is economically wise. However, the rest of me isn't thrilled with the aesthetic of the dome or party tent look for a backyard oasis.

 

[najetset]

Condensation from heating cold water mixing with flue gasses will corrode a heater. Most heaters have a minimum operating water temperature. If you are going to run the heater in the winter you have to keep the water temp above around 70F.

Good point as well. Hopefully won't be an issue for me!

For the 2019 pool season, we'll be adding in two 10ton VRF heat pump systems. Currently we don't have AC in our house and the summers can get very hot here, so this will be a nice add, I'm going for the VRF versions of the heat pumps, so that we can just treat the pool as another 'Zone', effectively we'll be taking all the heat from the house during summer and dumping it to the pool. This 'first stage' heating will work during the summer months when we need AC to cool the house, the shoulder months when we don't really need to heat or cool the house, the heat pump will heat the pool as a normal pool heat pump would, and then the extended season I have the NG boiler which is an extremely high efficiency Lochinvar condensing boiler (~96% efficient) which is sized sufficiently to heat the house(October to May), domestic hot water, the pool (for April to October), and the driveway melt system (October to May).

 

[ajw22]

I have the NG boiler which is an extremely high efficiency Lochinvar condensing boiler (~96% efficient) which is sized sufficiently to heat the house(October to May), domestic hot water, the pool (for April to October), and the driveway melt system (October to May).

Interesting setup. What is going to heat the pool November to March?

 

[najetset]

Interesting setup. What is going to heat the pool November to March?

Well I suppose thats one of the things I'm looking to get out of this thread and others like it. The quick and easy would be to continue using the NG boiler. It is sized to handle the load down to about freezing, but was not sized to handle it during -30C temperatures. I'm not exactly sure what the extra demand would be in that case, or if some other heating source would be better ie. electric resistive.

 

[ajw22]

Well I suppose thats one of the things I'm looking to get out of this thread and others like it. The quick and easy would be to continue using the NG boiler. It is sized to handle the load down to about freezing, but was not sized to handle it during -30C temperatures. I'm not exactly sure what the extra demand would be in that case, or if some other heating source would be better ie. electric resistive.

It is all about BTUs. NG has the most energy at the least cost to heat water. Unless you have a power plant next door electric resistive heat cannot give you the BTUs you need efficiently.

You need to minimize heat loss from the water to reduce the size of the heat demand in -30C temperatures. Then your existing setup may be able to handle it.