Hayward Pump questions

[mas985]

I wouldn't go any higher than a 3/4 HP. In fact, I am running a 1/2 HP (full rate) pump with solar and a 25' roof without any problem. The panels prime fine in less than about a minuite.

Also, I am surprised you need to restrict the returns at all. You shouldn't need to do that with only a 25' rise. Again, I am able to prime my panels with about 15 PSI. Have you tried it without the restriction?

[rhosk]

I wouldn't go any higher than a 3/4 HP. In fact, I am running a 1/2 HP (full rate) pump with solar and a 25' roof without any problem. The panels prime fine in less than about a minuite.

You've convinced me, thanks.

Also, I am surprised you need to restrict the returns at all. You shouldn't need to do that with only a 25' rise. Again, I am able to prime my panels with about 15 PSI. Have you tried it without the restriction?

If I run it without the restriction, it bubble-burps every several seconds or so. Not a major problem, but it does cease when I restrict it

Regarding the electrical... has anyone purchased a new pump recently? Will I just be able to remove my current cord and install/wire it on the new pump? Or have things changed in that arena?

[mas985]

Do you currently have the SP2605X7 pump (uprated 3/4 HP)? If so, that pump actually has a lower head curve than my 1/2 HP pump which might explain why you have having some trouble with priming. What is the filter pressure when you don't have the extra restriction?

[rhosk]

Hi Mark,

No trouble with priming, just the air. The pump model number is SP1605 Z1...

Without the washers in the outlets, I get about 17 PSI or so. It's not much of a difference at all with/without restriction, but it does get rid of the air when I increase the pressure slightly.

[waste]

Ron, I'll gladly leave pump size and flow issues to experts like Mark and Al (if I know a little about what they're talking about, it's only from reading their threads )

However, it's easy, usually, to see if the shaft seal has failed, all you need do is look for a drip at the motor/ housing interface when the pump is running (a puddle coming from under said interface is a good indication as well)

Good luck with keeping the motor running another 15 years.

[rhosk]

However, it's easy, usually, to see if the shaft seal has failed, all you need do is look for a drip at the motor/ housing interface when the pump is running (a puddle coming from under said interface is a good indication as well)

Nope, no leaks around the pump.

The VRV can be installed almost anywhere down to a few feet above the pad but on the supply side only.

Here's a depiction of my setup (VRV at the top left):



Do you think if I put the VRV at the bottom right of the panels it may take care of the air issue?

[mas985]

It looks like you only need about 2 PSI more to close the valve so given the height difference and the fact that you are not going through the panels, there is a good chance that it may work.

If the VRV is the kind that fits in the end of the panel header, then it would be simple to check.

[mas985]

Hi Mark,

No trouble with priming, just the air. The pump model number is SP1605 Z1...

Without the washers in the outlets, I get about 17 PSI or so. It's not much of a difference at all with/without restriction, but it does get rid of the air when I increase the pressure slightly.

That is actually the motor number but it is the motor for the SP2605X7 model pump which is a 3/4 HP uprated pump. The SP2607x10, an uprated 1 HP, is actaully closer to the 1/2 HP pump that I have in terms of performance (not all pumps are created equal).

What may be happening is that the pressure at the vacuum release is not high enough to completely close off thereby allowing air into the panels. So the panels go through a cycle of air and purge which is why you see bubbles come out periodically. So the issue could be with the valve itself.

However, 17 PSI should be more than enough pressure to close the VRV and prime the panels unless there is a lot of head loss between the filter and VRV. What size pipe do you have going to the panels? Where is the VRV located? Sometimes you can move the valve to the supply side of the panels so it closes off easier.

[rhosk]

Hm, this thread has strayed off topic, but as usual, I'm learning more and more!

However, 17 PSI should be more than enough pressure to close the VRV and prime the panels unless there is a lot of head loss between the filter and VRV. What size pipe do you have going to the panels? Where is the VRV located?

I have about 40 feet of (2") PVC level ground, then the 25' rise to the panels, then the same returns. The VRV is at the top most position of the panels.

Sometimes you can move the valve to the supply side of the panels so it closes off easier.

This sounds interesting. I may have to try this.

[mas985]

My main point in addressing the pressure issue is that you would be better off energy wise with the 3/4 HP pump as long as you can get it to work properly. If you can move the VRV, you may not need to have the washers in the return in order to use a 3/4 HP. This will also improve the efficiency of the setup.

The VRV can be installed almost anywhere down to a few feet above the pad but on the supply side only. Some installers will put it a few feet above the pad so it is easily accessable for replacement. This works well for two speed pumps on low speed but is not recommended for very hot climates where the water can sit in the panels and heat up enough to soften PVC.