Stenner Pump Question - Start Up

[dschribs]

I just installed my Stenner pump. I'll be opening the pool on Saturday.

I want to add bleach manually for the first week or so just to get to my normal baseline. I have yet to add bleach to my storage tank or even turned the pump on. The lines in the Stenner have no bleach in them.

I have the injector threaded into the return line and everything is ready to go.

Any problems with starting up the pool and just letting the pump sit for a week or so? I have the 100 psi pump w the check valve.

 

[dsmith99]

No problem at all, water will not flow backward through the injector check valve. When I was getting the pool opened up this spring I ran the pool pump a couple hours before I even got the tubing fished out of the basement and reconnected. As long as the rollers are expanded, the pump itself will also act like a check valve. When you're ready the pump primes itself easily, just turn it on and let it run.

If I remember correctly the pump was shipped with the rollers retracted and I had to expand them. Here is a video that makes it easier to understand than the manual.

 

[GDN]

I would agree, no issue letting it sit, but if you are going to dial in your chlorine manually before starting the pump, take the time now to test your pump and see how much you really get from it using water. My pump was rated at .89 ounces per minute, but testing before I added chlorine to the tank I truly got about 1.2 ounces per minute. So take the time now to see exactly how much your pump puts out, you'll want to know so you can set it correctly after you decide how much chlorine you want to put in daily.

 

[dschribs]

I would agree, no issue letting it sit, but if you are going to dial in your chlorine manually before starting the pump, take the time now to test your pump and see how much you really get from it using water. My pump was rated at .89 ounces per minute, but testing before I added chlorine to the tank I truly got about 1.2 ounces per minute. So take the time now to see exactly how much your pump puts out, you'll want to know so you can set it correctly after you decide how much you want chlorine you want to put in daily.

What did you use to measure 1.2 ounces? My measuring cup STARTS at 2 ounces.

Something doesn't sound right here...

Could you have read the output on the Stenner chart wrong? Do you maybe have different internal tubes than what you think you have?

Has anyone else tested the output of their pump? This is the first post where I have seen someone do this. Stenner indicates my pump disburses .89 ounces per minute and that's the measurement I had planned on using. I just assumed as "sort of" a scientific instrument - the .89 was dead on.

I would think that a pump designed for purifying water and/or industrial uses would be VERY accurate in terms of the output ratings from the factory.

If they were not accurate, what would be the point of an adjustable output metering pump? It seems far fetched that one would need to test the output at each and every setting on the pump.

 

[GDN]

I agree, I was surprised that it wasn't a little closer to their .89 ounces since they seemed so precise with that number. I did (2) 10 minute tests because I didn't think one minute was fair on starting and stopping accuracy. I primed the pump and had water flowing. Put the tube in a 2 cup measuring cup and timed it for 10 minutes. I had 12 ounces of water at the end of 10 minutes, both times. The pump box says it was what I ordered (10 GPD) and I didn't think too much more about it, I just wanted to test what my pump was putting out.

For a few weeks before installing I'd been adding about 32 ounces a day, I set the stenner up to pump that amount and I'm staying right at my same FC and have been now a few weeks, so I think the testing was fairly accurate.

It's pretty simple to run a test, I'd be interested to know what others get from their pump.

 

[joshua5438]

I installed my stenner 85MHP17 about a month ago. The spec sheet says it will pump 1.51oz per minute. I tested it many time and every time I came up with 1.6oz per minute. I ran most of my test for 5 minutes and it always landed dead on 8oz. So I feel that mine closely matches the stated pump rate.

 

[atttech-2]

There are many factors I can think of that could affect output. amount of lift on the suction side, temp of the liquid being pumped, temp and age of the tubing, back pressure on the discharge side and the list goes on. While interesting it is probably not worth worrying about a potential +/- a couple ounces per day in thousands of gallons of water especially since the strength of the chlorine being used has a much wider margin of error.

I would just go with the pump spec and adjust up or down from there. If I recall it took me a couple of weeks to get my pump times dialed in.

 

[dschribs]

There are many factors I can think of that could affect output. amount of lift on the suction side, temp of the liquid being pumped, temp and age of the tubing, back pressure on the discharge side and the list goes on. While interesting it is probably not worth worrying about a potential +/- a couple ounces per day in thousands of gallons of water especially since the strength of the chlorine being used has a much wider margin of error.

I would just go with the pump spec and adjust up or down from there. If I recall it took me a couple of weeks to get my pump times dialed in.

I'm going that route. Thanks!