Smaller two speeds may not push enough. A larger unit may be called for or a variable speed.

Scott

cnr1089....I would call Hayward Tech support to see what they have to say.

I suspect the 2 speed has enough flow for the generator....most 2 speeds at low speed deliver around 40-60 gpm for typical head pressures. This is greater than most generators require which is about 30 gpm to work.

When you call Tech support, they will likely ask for the pump model number and filter gage pressure.

If you would like to post this information here, that would help also.

Hope this helps.

The pool builders called Hayward while they were at my house and went over our system, basically because the pool equipment is above the pool and > 30 feet and we have a Heat Pump (which is about 10 feet away from the other equipment) and Propane heater, that the pump cannot push the water at low speed.

I think the Two Speed pump we have is 2.5 HP (I could be wrong). I can get the exact details tomorrow. I am really trying to figure out if I should push the pool builders to help me out here, since they designed the system, installed it, etc. I think I should, but I don't really have much to stand on, because they will likely just say "Just run at full speed longer." I hate having a very expensive brand new thing that isn't working how it is supposed in the first year!

A 2.5 HP should have way more than enough at low speed. I have 1/2 HP and even that is enough at low speed. Goldline units don't need much at all for flow rate.

However, it could be an indication of something else going on. Check the flow switch and make sure something didn't get stuck in there.

Also, please post the following.

Pump Model
Filter model
Pump height above/below water level
Pipe diameter
Number of suction runs from pool to pad
Filter pressure on high speed

I was wrong about the pump, here are my specs:

Hayward NorthStar 2HP (dual speed) pump (I misread the THP as being 2.5, thinking that was the HP pump):

Hayward DE6020 Filter (120GPM)

Looks like 26 Psi? on high:

Here is a picture of my equipment (note, the heat pump is to the far right, on the other side of my air conditioner units):

And here is the pool equipment in relationship to the pool. I would say it is like 30-40 feet away:

Note, the equipment is about 4 feet higher then the top of the pool....

Oh, the pipe diameter (according to the pool guy) is 2". I am not sure how many suctions, but we have a main drain (although it is split in two with two actual drains, I am pretty sure it is just one pipe to the equipment) and two skimmers (not hot tub).

One last thing...I still get no flow when I do a backwash and clean out the filter basked....although it takes longer after turning the pump down from full speed (I have never timed it, but no flow usually doesn't show up right away when going from full to low speed).

The pressure is a little high and indicates quite a bit of head loss. I estimate somewhere around 80 GPM with 73' of head on high speed and 40 GPM with 18' of head on low speed. So that should be more than enough flow rate to trip the flow switch.

I would focus on the flow switch. Is any water bypassing the flow switch because you have two heaters?

Also, the flow switch much be installed in the proper direction. Check the arrow on the switch and make sure it is pointed in the correct direction.

A picture of the pad plumbing might help.

When I see a large DE filter showing me 25 PSI when clean, then there is a substantial blockage of some sort. In this case, I suspect it is the heaters. I am also assuming that the cell has been checked for scale, not an unusual event with a newer plastered pool.

I am assuming the heaters are in series, the gas heater and then the heat pump. The two of them need some plumbing modifications.

I think the best option is to plumb the heaters in parallel with valves set up so you can shut the flow to either, both, or bypass them. I doubt you would use both at the same time so eliminating the unused one or both from the path will help a lot.

I would also add a shortcut valve between each heater's intake and exhaust. This would be used when both heating and high speed are used. Neither heater's water pathway should be asked to take the full brunt of the Northstar's flow at high speed.

I suspect the bigger restriction will be found to be the heat pump.

I don't know if you can automate this fully but it would likely solve this challenge.

Scott

poolguynj:

I do remember the pool guy talking the hayward guy about doing some sort of bypass of the heaters, etc....

Should I push for them to re-arrange these, rather then push for the Variable Speed pump?

Here are some more pictures of the pad area:

cnr1089....Thanks for the additional info.

With the reported filter gage pressure, I also suspect too many restrictions between the pump and the pool.

With the choice of a 2 speed pump, clearly, you're energy concious. Energy savings only comes with low speed filtering and optimizing plumbing hydraulics.

In your case, you have the pump that is capable of low speed but unfortunately do not have the optimum hydraulic design.

Getting a variable speed is only a band aid to fix the symptom and will result in higher operating costs due to higher speed operation.

As poolguy recommends....running the heaters in parallel will help significantly. Also, having bypasses for high speed operation is recommended. I think all the heating manufacturers recommend this in their installation manuals.

These plumbing changes will require valving and preferably automation...hopefully your current automation system has the capability of handling the extra automation requirements to make the system work conveniently without having to run to the pad when needed.

Hope this helps.

cnr...forgot to mention...before going too far...have you had the flow switch checked as mas985 mentions. It would be regrettable to make all the changes mentioned above when the root cause was the switch itself (incorrect orientation, debris, teflon tape debris, bad switch, bad electrical connection, etc.).

Hope this helps.