When to prime the pump

[eskewj]

I've owned a pool for about 1 month so far and up until now I didn't realize that you were supposed to prime the pool pump! I watched some videos on Youtube about how to do this, but it is not clear when this step is necessary. I reasoned it was not necessary because the pump seemed to "self-prime", although a lot of air was getting into the lines.

Here is my understanding for when it makes sense to pour a bucket of water in to help things along:

1. After backwashing the sand filter.

2. After cleaning the pump strainer basket.

Situations where you DON'T need to prime the pump:

1. Turning the pumps on and off under daily cycling. This is probably obvious because if the pump is on a timer, you wouldn't be around to prime when it kicks on. However, not sure how long between cycles the system stays pressurized.

Any helpful feedback is appreciated!

 

[jblizzle]

Most pumps should self-prime ... assuming it is not WAY above the pool water level. If you do not see air in the pump basket after a few minutes, you are fine and no need to do anything other than put the lid back on and fire it up and purge the air out of the filter (assuming you do not have a top mounted multi-valve which does not have an air release valve).

 

[eskewj]

Thanks for the reply. So you're saying that as long as I stand there long enough to make sure it sounds normal after startup, there is no need to add the water beforehand? I have an air release valve on top of my filter and the pump sits above water level.

 

[jblizzle]

Correct. You should see the water start flowing in to the pump pretty quickly and the bubbles should be mostly gone in a few minutes.

 

[eskewj]

Cool thanks. I guess my first instinct was correct in that if it manages to self-prime, no need to pour in more water. Glad I wasn't doing damage this whole time!

 

[mas985]

Thanks for the reply. So you're saying that as long as I stand there long enough to make sure it sounds normal after startup, there is no need to add the water beforehand?

I think it is always a good idea to make sure that the water level in the pump basket is at least up to the inlet pipe so you may need to add some water to the pump basket. This makes it a little easier and faster for the pump to prime. If the water level is too low, it can take much longer to prime which is hard on the seal.

 

[eskewj]

mas985,

So if I understand correctly -> just because the pump will self-prime, it doesn't mean it is good for the system.

 

[jblizzle]

It is all relative ... 20 seconds is not problem ... even a few minutes to fully prime is probably not that bad as some water will be moving through and cooling things, but if it is running dry with no water movement at all for a many minutes, that could cause problems.

Just make sure the pump is filled to the intake opening, cover it and fire it up. I guess I have never worried about adding water as my pump is barely above the pool water level. I see water movement in seconds.

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BTW, when you are just backwashing (like in 1 in your first post), you do not open the pump so there is no where to pour water. You should only loose prime if you open up the system (like the pump basket almost immediately or if you open the filter for long enough that the water can all drain back through the pump).