HELP!!! ME select a pump for my pad renovation / addition of 2 story solar (pump and automation challenge)

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C

CRUSH-IT!

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Jul 29, 2017
75
orlando, fl
Pool Size
24000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Hayward Turbo Cell (T-CELL-5)
First,
This Site is the BOMB! very helpful and very well organized.

I will be installing solar. (heliocol) This seems to me a good choice. (very low frictional loss). Once the flow is established the siphon effect reduces the hydrostatic pressure such that the pump can downshift but the pump must run on high to fill the panels and create the siphon initially. The automation options must offer this??? I can't find it anywhere. How do I accomplish this. I am primarily looking at pentair intelliconnect. Jandy aqua link and hayward. I will be adding a VS or VSF with the addition of Solar and new automation.

Thanks
 
It,

I don't believe that the IntelliConnect can control solar, as it have no ability to control automated valves..

While solar cells may cause a siphon effect, I have never heard it being used in a pool setting. All solar systems that I am familiar with, only turn the pump on, when heat is called for and off when not called for..

Thanks,

Jim R.
 
The pump will see a hydrostatic pressure equal to the top of the panels ie: 40' plus frictional losses in addition. Once the panes begin to drain the drain pipes create a siphon that reduces the hydrostatic pressure. It is usually lowered to roughly the height of the panels minus the height of the vacuum relief valve. My vacuum relief valve will be 7' off of the ground. The top of the panel is about 40' so the initial hydrostatic pressure to fill the panel will be 40' but will drop to about 7' after flow is established. I would like the pump too downshift accordingly. ie: run on high for the first three minutes then downshift.
 
CRUSH-IT! said:
Once the flow is established the siphon effect reduces the hydrostatic pressure such that the pump can downshift but the pump must run on high to fill the panels and create the siphon initially.
Click to expand...
The siphon effect is less than most people think because the panels are not designed to operate under vacuum.

The solar systems come with a vacuum breaker, which limits the amount of siphon that can be created depending on where the vacuum breaker is placed.

The Pentair Intelliflo VSF has the option to operate in flow (GPM) or constant speed (RPM) mode.

In flow mode, you can set a flow rate for the solar system in the Pentair IntelliCenter and the pump will maintain the set flow in GPM even if the total restriction changes.

Note that the flow is estimated by the pump software based on the pump power usage. So, I don't think that the flow in GPM is super accurate, but it's likely close enough as long as the pump is not operating at either end of the performance curve.

See page 29 in the below manual that shows the operating range for flow control on the pump performance curve, which shows that the pump flow estimate is not accurate near the ends of the curves.

 
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Thank-you for your rapid response.

I had Fafco panels that absolutely were not rated for suction. That manufacturer recommends placing the vacuum relief valve at the top of the panels but would allow it to be placed at the bottom of the panels. (still pretty high so you might get -5psi at the top header) Heliocol recommends putting the valve "above the top of the filter".... REMARKABLY LOW! I was surprised that that there was no caveat for a high roof. This implies they can tolerate near total vacuum conditions provided there is flow so the panels are not super hot.
 
CRUSH-IT! said:
Heliocol recommends putting the valve "above the top of the filter".... REMARKABLY LOW! I was surprised that that there was no caveat for a high roof. This implies they can tolerate near total vacuum conditions provided there is flow so the panels are not super hot.
Click to expand...
Ok, maybe verify with Heliocol because the roof is pretty high and you don't want to risk damaging the panels.
 
Will do.

Does anybody know an automation set up that can set a circuit as "flow dependent" and ramp up the pump for a brief period at the initiation of that circuit???
 
CRUSH-IT! said:
I like the IntelliFlo option. would like to be able to do it with a VSP instead of VF.
Click to expand...
Using a VS would be tricky. You could try finding a speed that would prime the panels and provide at least 5 gpm before the siphon effect kicked in and then the flow would increase to the required flow as the panels reached prime and the siphon kicked in.

You can get the VSF pump and try VS mode to see if it works or switch to VF mode if there is not a speed that will prime the panels and provide adequate flow on reaching prime.
 

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JamesW said:
The siphon effect is less than most people think because the panels are not designed to operate under vacuum.

The solar systems come with a vacuum breaker, which limits the amount of siphon that can be created depending on where the vacuum breaker is placed.
Click to expand...
This is the key. There must be enough pressure in the panels to close the vacuum relief valve(s) and keep them closed throughout operation. If you reduce flow, at some point the VRVs will leak. So forget exploiting the siphon effect. You need pressure from the pump.
 
I was not sure whether to post this in pumps or automation. I am planning a pad renovation. I will also be adding solar. the top of the panels will be close to 40' The vacuum relief valve will be about 7'. There will be considerable siphon when flow is established. so when the solar comes on the pressure will go to about 25psi or so. Once flow is established the pressure head will drop to about 14 (estimate). So, ideally i would like the pump to come on at full speed for a couple of minutes each time the solar comes on and then downshift. to save energy. I do not want to run the pump on high all day.

pentair variable flow has been recommended to me.On first glance this is very attractive. set the flow and the pump adjusts accordingly... problem solved. I have however seen on other sites that this is a highly problematic solution. I guess the pump has a number of protective features to prevent deadheading and to assure priming etc. apparently the pump gets freaked out by the rapid change in pressure senses it is not primed and shuts down. multiple owners have expressed that after much conversation with pentair their pump was swapped out for a VS pump.

This brings us to the VS pump. I can schedule a VS pump to turn on the solar at 11:00 and run on high for 5 min. then schedule the pump to run on 80% for 6 hours. The problem is if the solar valve turns the solar off, (temp achieved or overcast) The pump will not be able to fill the panels at 80% if the valve reopens.

Does anyone have insights or recommendations. i am searching for a solution that works for some automation and pump combination. As I have not selected the replacement yet.

Thanks
 
CRUSH-IT! said:
I guess the pump has a number of protective features to prevent deadheading and to assure priming etc. apparently the pump gets freaked out by the rapid change in pressure senses it is not primed and shuts down.
Click to expand...
The pressure change problems are with the SVRS model, which has antientrapment built in.

Just avoid the SVRS model and you should be fine with the VSF model.

www.pentair.com

IntelliFlo® VS+SVRS Variable Speed Pump

,
www.pentair.com www.pentair.com
 
The Pentair automation is confusing and not easy to program.

You might be able to assign an egg timer to the heater circuit for 1 or two minutes at a higher speed than the pump speed assigned to the heater circuit to get the panels primed.

The higher speed should override the lower speed set for the pump speed assigned to the solar circuit.

The higher speed should be activated by the egg timer assigned to the solar circuit when solar is activated and cause the pump to run at the higher speed for the amount of time set in the egg timer.

Maybe someone here knows or maybe check with Pentair to verify.

The non-SVRS (Safety Vacuum Release System) VSF pump should also be a viable option.
 
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I think that Pentair is the only variable flow pump.

Pentair has several patents on the power to flow technology.

Hayward has disputed the patents, but I don't know the status of the disputes or if they have been resolved.

Ideally, all pumps should come with a flow control option even if they have to install a flowmeter and/or pressure sensors.
 
You can program most automation to run a specific speed when the solar calls for heat. Usually buried deep in the menus somewhere.
Waterway, a brand seldom spoken about here, also has a variable-flow pump. Remember that most brands of automation will only communicate with their own brand of pump. Waterway has automation that will control most name-brand pumps on the market today.
 

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