Existing union dilemma with pump replacement

[jpa]

I am looking into replacing my pool pump, a Sta-Rite MPRA6E-147L. It's very old, the bearings are shot... and I do want a VS pump. I've been calling pool places in my area since February and I've heard everything except "yes, we can do it". I think I'll just have to figure this out on my own to make it happen.

The thing that I'm the most unsure about is how my current pump's suction side is connected. I have a 3-way valve with a half union glued to it, which screws directly onto the pump. I've been looking for any kind of a fitting that would accept the union nut and let me transition to something standard, but I haven't found anything. Either nothing exists, or I don't know what to look for.

I'd hate to have to cut off the 3-way valve and plumb in a new one for this, but do I have any other choice? And if do end up having to do more plumbing that I'd like to, are there any obvious improvements I could be making while I get everything back together?

 

[Poolbreh]

What does that 90 say 2” or 2.5” it looks like 2.5”. You can go over or in on the diverter valves. So you have plenty of options other than cutting the diverter valve out.

 

[Texas Splash]

Welcome to TFP! I suspect some PVC surgery may be in order either way. It sounds as though you ideally would like to leave the current intake union nut on there and not have to disturb the 3-wsay connections. But even if you found the corresponding other half of the union to go to it, you would need room for a small straight piece of PVC and an adapter to screw into the new pump inlet. That would require pushing the pump backwards a bit. That might be okay to save work on the 3-way side, but could require modifying your line on the back-end from the pump outlet to the filter.

 

[IUsedToSail]

I doubt that it is 2.5" plumbing as that model pump is only 1HP.

Sta-Rite Dyna-Glas Uprated Pool Pump | 1.0HP 115V/230V | MPRA6E-147L

Pool Supply Unlimited has some of the best prices when shopping for Sta-Rite Dyna-Glas Uprated Pool Pump | 1.0HP 115V/230V | MPRA6E-147L

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There is something strange going on there after the filter outlet... looks like it necks down to possibly 1.5" via a reducer fitting.

 

[jpa]

What does that 90 say 2” or 2.5” it looks like 2.5”. You can go over or in on the diverter valves. So you have plenty of options other than cutting the diverter valve out.

It's 2". I use a wide-angle lense to take the picture which makes that elbow look huge. But I can't figure out what you're suggesting here. I think my problem is that the half union is glued directly on the valve and there's nothing I can attach to that, other than another obsolete pump.

There is something strange going on there after the filter outlet... looks like it necks down to possibly 1.5" via a reducer fitting.

Yes, there's a reducer. The 2" pipe coming out of the filter gets reduced to 1.5", followed by a tee that splits to the heater and the chlorinator using 1.5" pipe. On the other side of these, the pipes connect to the 2" line to the pool with a tee fitted with reducer bushings.

Besides my inexperience with pool plumbing, one thing that makes me want to avoid changing the existing plumbing too much is, the lines too the pool are embedded in the concrete pad. If I accidentally create a small catastrophe, I'll be looking into busting concrete, instead of just digging a little deeper to get to good pipe. Maybe I'm just more nervous about this than I need to be.

 

[Poolbreh]

But I can't figure out what you're suggesting here.

It tells us the size of pipe, valve, and union. The pad presents a problem. If you attach the second half of the union you would probably have to use a schedule 80 nipple and have union flush with pump and still have to replumb return side. It would push you close to the end of the pad.
You could cut the union part that has female threads and with a little 1.5” glue inside the valve and use a 1.5”-2” heat union. You would still have to replumb return.
Or you can chip/heat gun the union off the valve and use 2-2” heat union and replumb return.
I personally would do the last option lol. But it’s what you feel comfortable with. Literally a hundred options.

 

[Poolbreh]

I’m wondering if a intellipro vs would fit. The dimensions seem the same, not sure about the threading.

 

[jpa]

You could cut the union part that has female threads and with a little 1.5” glue inside the valve and use a 1.5”-2” heat union. You would still have to replumb return.

Certainly a possibility. I wouldn't have even thought of this, thanks for the tip.

Or you can chip/heat gun the union off the valve and use 2-2” heat union and replumb return.

I've seen youtube videos of people taking PVC fittings off with a hack saw and a heat gun, and I was already wondering if I could make this work. I think I'll give this a go.

I’m wondering if a intellipro vs would fit. The dimensions seem the same, not sure about the threading.

I didn't even look at Intellipro because it's such a big difference in HP... but it's variable speed, I suppose I would just need to dial in the speed I want. The dimensions are close enough that it might just work in principle, except that my current pump connects using an external thread that the intellipro doesn't have. I am wondering if I should call Pentair tech support and see what they think.

I have been assuming that no matter what, I will have to line up the suction port with the current piping by raising the pump, and make a new leg from the pump to the filter, and adjust the length of the return from the filter. And all of that seems relatively simple.

All in all, I feel like a plan is starting to fall in place. I really appreciate the advice.

 

[IUsedToSail]

If you don't want to cut anything it looks like your pump may still be available by special order... as are the parts.

Sta-Rite Dyna-Glas Uprated Pool Pump | 1.0HP 115V/230V | MPRA6E-147L

Pool Supply Unlimited has some of the best prices when shopping for Sta-Rite Dyna-Glas Uprated Pool Pump | 1.0HP 115V/230V | MPRA6E-147L

www.poolsupplyunlimited.com

I haven't bought anything from these folks but I did ask for a quote on a filter two weeks ago and the guy responded in about 10 minutes.

 

[Poolbreh]

I am wondering if I should call Pentair tech support and see what they think.

I think that’s a good idea. You should confirm. If it did match it would be an easy install. But intelliflo vs is the best IMO.