Pump/Plumbing/Solar Questions

[jblizzle]

The check valve for solar should be right after the filter and before the solar valve. There should be a second check valve on the return solar before it gets plumbed back into the main return line.

I understand I need 2 check valves: I need to add one after the filter and plan to replace the current one after the solar to the more efficient flapper style.

You could actually plumb the solar return after the heater if it is easier.

Currently the heater exit pipe goes horizontal PAST the return pipe. I am suggesting to just drop it straight down to the return pipe with just 2 90s.

Still not getting it . Currently all the water goes through the heater and then though the solar if open. Most diagrams I see say to go through the solar if open and then through the heater, which is what I was trying to do. The easiest would be to just leave the heater before the solar and add the bypass there, although then I could not run both (might be rare to do this except for special weekend occasions in the shoulder seasons.

It almost sound like you are suggesting I enter the heater before the solar, but return from the heater AFTER the solar. Seems like even with the bypass open, the least resistance might be through the heater, and not going to the solar. Or did you mean to bring both the inlet and outlet of the heater to the return line after the solar?

For the new suction, you might be able to find a screw in cover. Just look at some online places that have fittings and see what will work. Either dual two ways or a 3-way would be fine.

I will see what I can find. Had not run across a screw in cover yet.

 

[mas985]

I was suggesting to enter solar before the heater right after the filter and check valve but exit solar after the heater pretty much where it is right now but with a larger pipe. Basically bypassing the heater all together when solar is engaged although you will have a separate bypass anyway.

 

[jblizzle]

I was suggesting to enter solar before the heater right after the filter and check valve but exit solar after the heater pretty much where it is right now but with a larger pipe. Basically bypassing the heater all together when solar is engaged although you will have a separate bypass anyway.

Got it ... will have to decide how I want to do it.

Looks like the Superflo -1A is almost 20% cheaper than the Whisperflo -3 AND would cost less to run AND may use the same fittings as my existing pump ... that is starting to look pretty good, especially if I can add the 2nd suction line to help with flow.

But, I am concerned that the female threads I have on the fitting in the pool may be smaller than anything I have found. I have seen some screw-in suctions housings with 1.5" male threads, but an afraid my pool may be 1.25" or even 1" female. I may post a separate thread for suggestions on this after I confirm the size at home to see if anyone has thoughts.

 

[jblizzle]

Well, I did a little investigating and sure enough I found the mystery pipe capped about 1" below the ground right next to where the waterfall pipe was going down into the ground. Also discovered that this capped line has a small leak at the fittings (that will be replaced when I run it over to the pump).

The pipe is another 1.5" so that would give me 2x 1.5" suction lines Still have not unscrewed the "plug" that is in the pool ... obviously not doing a very good job plugging But I am sure it is not a 1.5" female thread and is smaller than that. Although it is kind of inside the normal pool surface in a divot. So, I am thinking I might be able to get a male 1"/1.25" to female 1.5" adapter and then screw in one of the drain covers I have seen and hopefully it will not stick out too far from the wall. Or maybe there are female drain covers?

While I know there are codes involved, I am curious how much suction I would get on that line assuming I setup a 3-way valve with stops that did not allow the main suction line to be closed completely. I would think it may not be able to hold anyone to the wall suction because the water from the skimmer would be lower resistance ... and maybe I could get away with not putting any type of cover on it. Although hair might be more of a concern than a hand or something. Of course I would test this before I let me kids anywhere near it. Thoughts?

 

[jblizzle]

Just made another discovery. The little plug I had in the pool was NOT the old waterfall suction line, but it was one of the old whip returns. The old suction line actually has a large eyeball currently in it (I have yet to figure out how to remove it) that is at least a 1.5" female threaded fitting, so fitting a drain cover may be way easier than I thought it would be.

So, Mark, you said that adding a suction line has multiple improvements. How much would the below numbers change when I have two 1.5" suction lines instead of just the one?

All of these estimates are with solar engaged on high speed:

WFDS-26/4: 60 GPM @ 71' of head & 1758 watts, 2.04 gallons/watt-hr, (6.4 PSI @ VRV)

WFDS-24/3: 58 GPM @ 66' of head & 1550 watts, 2.23 gallons/watt-hr, (5.7 PSI @ VRV)

SF-N2-1A: 52 GPM @ 55' of head & 1355 watts, 2.32 gallons/watt-hr, (4.1 PSI @ VRV)

SF-N2-3/4A: 44 GPM @ 40' of head & 1105 watts, 2.41 gallons/watt-hr, (1.8 PSI @ VRV)

Still think I am leaning toward the -1A, but curious about the added margin from the second suction line.

 

[mas985]

What was the clean filter pressure again with and without solar engaged on your current pump? I remember several numbers but I am unsure of which was the correct value. Also, did you want the numbers with or without the pad redo and heater bypass?

 

[jblizzle]

The idea was just to confirm added margin with the pad redo and solar active with the added suction line.

Currently it is 26psi on the normal returns with no solar.

Posted with Tapatalk ... sorry if I sound short ... hate typing on phone

 

[mas985]

The idea was just to confirm added margin with the pad redo and solar active with the added suction line.

Then I also need the current filter pressure when solar is engaged. It think you said it was 28 PSI but I want to confirm.

But after thinking about this some more, I would caution you to not rely too much on these estimates. You will be changing a lot of the plumbing and the solar panels so there are still a lot of unknowns. As I suggested before, you might consider changing the plumbing and solar first and then decide on the pump. Either that or just go with VS so there is no guess work.

 

[jblizzle]

Well, the solar has been removed and the new setup is not installed. I do recall the old solar giving about 28 psi.

Good point about the pump though ... well hopefully my current one will last until I have the time to get the solar back in and the plumbing changed (although that will be at least another month). I hate to plumb in the old pump and then have to cut sections out to plumb in the new one ... have to be sure to leave enough exposed pipe and hope the things can line up.

I found the solar pipes in front of the pad, so I think I am going to reroute them with the valve in front of the multi valve. It looks like I should be able to remove 7 of the 90 degree turns on the pad from the current setup when solar is active and adding the heater bypass. And several will be changed from 1.5" to 2" pipe and fittings. Although, the new solar will have many more 2" pipe fittings than the old setup.

I guess I will just work on getting this plumbing done after returning from vacation ... although the idea of being on the roof installing a solar heater when it is 100 degrees out and the pool is already in the 80s does not seem very fun

 

[mas985]

The pump temporary reinstall should not be a big deal because there are not many fittings between the pump and the filter. You should be able to reuse some of the existing plumbing. Plus when you have a new pump, you will only need to replace that section. To me it is worth it to get it right. Also, if you are so inclined, you can get a vacuum gauge to put on the suction side and that will help refine the numbers.

 

[jblizzle]

I will let you know when I get to all this.

My biggest concern with switching pumps is the suction side of the plumbing as there is not a lot of room between the pump and what will be a new 3-way valve for the new suction line. Most of the stuff I have should be reusable, so it may not be a big deal to do a final plumb of the new pump.

 

[jblizzle]

Got back from vacation and took a look at the deliveries I had gotten including the parts for my solar setup. Looking at the VRV I was surprised to find that it is spring loaded closed (based on mention here of a minimum required positive pressure to keep it closed). Is this different than other VRV?

Seems like I would need some negative pressure differential to even pull air into the system ... which makes me wonder how well the system will drain if it relies on the weight of the water to pull the valve open and let air in.

Maybe these just work differently than I expected ...

 

[mas985]

Got back from vacation and took a look at the deliveries I had gotten including the parts for my solar setup. Looking at the VRV I was surprised to find that it is spring loaded closed (based on mention here of a minimum required positive pressure to keep it closed). Is this different than other VRV?

There are several different designs. Which one did you get.

Seems like I would need some negative pressure differential to even pull air into the system ... which makes me wonder how well the system will drain if it relies on the weight of the water to pull the valve open and let air in.

That is the way all VRVs work. When the pump shuts off the weight of the water creates a partial vacuum at the VRV which opens it. It should stay open until the water drains at which point the pressure equalizes and then it will close.

 

[jblizzle]

It is a PVC one that apparently Heliocol typically uses. I could have gotten a brass one that they used to use, but the person I talked to recommended the PVC one. Not sure I made the right choice (although the prices were different where I actually bought from).

I guess I thought they were typically more "open" in that it required the water pressure to actually close it. The one I have seems pretty closed, which also seems to mean that air will not be forced out of it if I put it at the top of the panels (location is TBD) ... which is what I expected. So, apparently ALL the air in the system will be purged out through the pool returns.

Current plan is to get the pump (Superflo 2-speed -1A, delivered today) and pad re-plumbed sometime in the next few weeks ... life and all

Then worry about the solar install later (since the water is warm already and I don't want to be on the roof when the temp is 100+). Based on the pressures I get with the new pad and pump, then determine the best solar setup and location for the VRV.

 

[jblizzle]

Well, this morning I finally complete Phase 1 of the Equipment pad redo and have my water moving:
- Installed Superflo 1HP 2-speed motor/pump
- Added wall suction line
- Added unions on filter (good because I have a slow drip from one of the screw-in adapters to the multi-valve)
- Added filter check valve and solar valve and stubs to connect solar pipes (which are seen in the lower right of the 2nd photo)
- Moved Waterfall valve by all the other returns
- Reorganization results in removing five 90-turns from the normal path with no heater or solar. New solar layout will also remove 2 more 90s from the pad.

OLD:

NEW Phase 1:

Future Phases:
- Add solar return check valve on vertical stub
- Connect solar pipes to stubs
- Install the solar panels on the roof
- (?) Reconnect gas heater with Tees into the U with 2-way diverter valve between the inlet and outlet Tees, possible adding union ball valves to the high horizontal pipes to allow isolation.
- Install Hayward flow switch and SWG cell in large U before return valves (still need to buy a controller though)


Observations:
- Planning equipment pads is a pain
- Aligning fittings and cutting pipes to length to match the plan is a bigger pain
- When I cut the old pipes out, I noticed the water near the heater was rusty ... as such, I am not sure I am going to reconnect it.
- On high, I think the Superflo is a little louder than my dead Hayward RS pump/AO Smith motor combo
- On low, you almost can not hear it is on standing next to it and the skimming action is good


Questions:
- While the heater is not leaking, I imagine that having the rust in the water going back to the pool is not a good thing correct?
- Or could that have just been due to the stagnant water sitting in the heater for a few weeks?
- Would like to get some feedback on the flow rates:

Suction from skimmer only and return to eyeball returns only, and a clean newly charged DE filter, my pressure high speed pressure 15 psi and my low speed pressure is 4psi {hard to say how much I improved the equipment pad losses since the pump changed too}

Changing the suction to be both the skimmer and the new wall, the high speed pressure goes up to 16 psi ... this surprised me. Does this mean the flow rate was able to increase and therefore the pressure went up?

Those are the only pressures I got this morning. I am pretty sure when I also open up the whip returns, the pressure goes down some ... does this increase the flow rate? {Really wish I was able to do these calculations myself ... not sure how good Mark's old spreadsheet I have is}

Honestly, when I first turned on the pump and saw the low pressure I got a little worried about my solar working, but if opening up the other returns can help the flow rate (with a lower pressure?) then hopefully I will be OK.

Thanks again for all your help.

 

[mas985]

Changing the suction to be both the skimmer and the new wall, the high speed pressure goes up to 16 psi ... this surprised me. Does this mean the flow rate was able to increase and therefore the pressure went up?

Yes, you decreased suction side head loss by drawing from two paths instead on one which allowed the pump to produce higher flow rate. The higher flow causes slightly higher head loss on the return side which raises the pressure. However, the net total head loss is lower. Just the opposite will happen if you draw from one skimmer and have a cleaner attached.

 

[jblizzle]

OK, so on the other hand opening up additional returns logically reduces the return side head loss giving a lower filter pressure, but this also increases the flow rate correct?

I guess the thing that confused me is the filter pressure is certainly not directly related to flow rate. I suppose this is why it is critical for you to know the size and number of suction and return lines as this affects the filter pressure quite a bit.

So, now:
When I add my solar, the return head loss will go up, filter pressure will go up, and the flow rate will go down.

I suppose at this point there is no way to know the flow rate I can acheive through the solar until I get it setup and get some pressure readings.

I may just have to (well out of curiosity) get a pressure and vacuum gauge to put on the pump to get a better feel for the flow rates. Do the pump pressure measurements just replace the filter pressure in your calculations and you still need to know all the other information?

Wish I could have tried both pumps on my new pad to see how much the losses were really affected by 3 days of pad work in 100 degree weather

 

[mas985]

Yes to all your questions.

I suppose at this point there is no way to know the flow rate I can acheive through the solar until I get it setup and get some pressure readings.

I can estimate it if I can get some more details about how your solar will be setup.

Is your drawing still accurate and can you put pipe lengths on it plus add the amount of pipe for the drop?

What is the front and rear roof height relative to the pump level?

How many panels will you have (i.e. size)?

Where will your solar valve be or is that it after the check valve?