I recently purchased a home with a pool. It is inground size 40x20. I am trying to have the most efficient flow possible with my setup. There are 2 skimmer lines and one main drain line. All 3 are 1 1/2 inch. Then one single line is also 1 1/12 going into the pump. Should I make that 2 inch for better flow? I really have no idea what I’m talking about, it just seems logical to me. TIA for any insights.
Pool plumbing question from New pool owner
- Thread starter hammer64
- Start date
If you were running new lines end to end then yes but just at the equipment pad will make absolutely no difference so leave it be.
Ok. Thanks. I don’t know if this makes a difference, but the pump does not keep prime. It’s never fully filled with water. Even when it tries to prime at full speed. I was thinking maybe that 1 1/12 inch single line going into the pump made it harder than it needs to be on the pump
Bill1974
Well-known member
Not filling and loosing prime suggests that there is a leak on the inlet side (sucking in air when the pump is running) of the pump or one of the lines supplying it. Could be at the union, one of the valves on the inlet side or pump. Replacing the seals on the pump is pretty easy and cheap. I generally replace all the o-rings on my unions every year (pretty easy to figure out the size and order a bag of them pretty cheaply).
Changing the plumbing isn't going to make a noticeable different. Your plumbing looks well laid out and as simple as it can be. When there is a need to change a piece of equipment, then it might make sense to make changes. It's still not going to be significant. One thing to keep in mine is a longer straight section on the pump inlet (about a 12 inches is good). Sweep elbows are flow better than standard 90° elbows.
Changing the plumbing isn't going to make a noticeable different. Your plumbing looks well laid out and as simple as it can be. When there is a need to change a piece of equipment, then it might make sense to make changes. It's still not going to be significant. One thing to keep in mine is a longer straight section on the pump inlet (about a 12 inches is good). Sweep elbows are flow better than standard 90° elbows.
I just went all around checking every possible inlet union for air leaks. I used soap bubbles. I couldn’t find any bubbles getting sucked in anywhere. But then again I’m no expert and have zero experience to know of that’sa for sure way to tell
Bill1974
Well-known member
The leak would be sucking in air, so not the easiest to find. It's unlikely that you would be able to tell from using soap and bubbles. If you could it would likely be a large leak that you could see or hear easily.
When the pump is off is there any signs of water leaking from the pump, union on the pump inlet or the ball valves on the inlet lines? How quickly does the pump loose it's prime?
On the pump there are only a few possibilities, cover seal, rotary seal, drain plugs, inlet/outlet connections or a crack in the pump housing.
I assume the pool is not loosing water. If it is not loosing water, generally this would mean the lines in the ground and the skimmers are not cracked and leaking.
When the pump is off is there any signs of water leaking from the pump, union on the pump inlet or the ball valves on the inlet lines? How quickly does the pump loose it's prime?
On the pump there are only a few possibilities, cover seal, rotary seal, drain plugs, inlet/outlet connections or a crack in the pump housing.
I assume the pool is not loosing water. If it is not loosing water, generally this would mean the lines in the ground and the skimmers are not cracked and leaking.
No signs of leaks or losing water. It never gets itself primed all the way. And it’s a 3450 rpm max motor. So I would think it should have the ability to prime quickly. But running the pump at 2100 rpm the water level slowly goes down. I can never get the pump completely full of water
So o just cleaned out my pump strainer. To my surprise there was some blue pvc cement chips in the strainer. Just a couple. However I think that tells me there is for sure a leak at one these unions. I’m guessing when I used the soap bubbles it might have loosened it a little more? However I still can’t tell from where exactly. Should I just replace all the inlet piping from just out of the ground to the pump?
Not sure if this means anything. If I unhook the the out from the pump, what screwed into the filter. The pump will prime completely within 30 seconds, zero air bubbles. So water is just being pumped into my driveway. Maybe then the filters are clogged? Well, I put brand new fillers in, same result with no prime and air in the pump strainer. Again any diagnostic insight, TIA.
Let a slow stream of water flow from a garden hose over every connection on the suction side of the pump all while watching the pump lid for a change in suction and noise. Make sure the flow encapsulates the whole fitting/connection at once.
I made sure to take my time and be very methodical with the water. No change at any point.
Wasn't mentioned, make sure the water level is at midway or a tad higher on the skimmer opening so it doesn't suck air from the skimmer due to not enough water. Also make sure the weir door/flap at the skimmers are working properly and not getting hung up. To isolate the problem after all checks out lock off 2 of the 3 valves alternately and see if any one line is causing the air intrusion.
Bill1974
Well-known member
Looking over your equipment image. Looks like you have somewhat restrictive plumbing. Three 1-1/2" inlet lines and one 1-1/2" return going though a DE filter and a heater. Should not be a contributing factor in loosing the prime. It might be a factor in purging all the air out after it primes, but I doubt it. My pool was similar, I made all home runs when I replaced all the lines.
If you close off all but one of the inlets does it change anything? This should help eliminate or isolate if one of the ball valves is causing or contributing to this.
If you close off all but one of the inlets does it change anything? This should help eliminate or isolate if one of the ball valves is causing or contributing to this.
I'd open the pump union and lube the O ring and then ONLY hand tighten. Over tightening will cause air leakage.
Water level and doors are good, tried each individual line into the pump by itself, so other two turned off. Tried them all for 30 minutes each. I did not noticed any more water or less air in the pump strainer view port. Thanks for all the diagnostic tips btw.
Tried the valves no luck. Are you referring to the line that goes to 1 1/2 inch pvc that goes into the ground and to the return jets?
Bill1974
Well-known member
Lid on the pump, some threaded connected on the inlet side, the union the inlet is letting in the air. Or maybe a glue joint is failing.
If any gasket is stiff, cracked, hard, has marks, etc replace them. Also look over the sealing surfaces, check for cracks, nicks, dirt, etc.
Yeah looks like you have one 1-1/2 return going to the return jets. This is some what of a restriction, but it's not contributing to the air leak on the suction side or I doubt it. As you saw when you disconnected the pump outlet and the air purged out. More flow just masks the air leak. Or the restricted outlet is limiting how much suction can be created on the inlet side and mask the leak. Loosing prime is the issue and air in the pump is not great for it either.
If any gasket is stiff, cracked, hard, has marks, etc replace them. Also look over the sealing surfaces, check for cracks, nicks, dirt, etc.
Yeah looks like you have one 1-1/2 return going to the return jets. This is some what of a restriction, but it's not contributing to the air leak on the suction side or I doubt it. As you saw when you disconnected the pump outlet and the air purged out. More flow just masks the air leak. Or the restricted outlet is limiting how much suction can be created on the inlet side and mask the leak. Loosing prime is the issue and air in the pump is not great for it either.