Wiring 2-Speed Whisperflo Motor & Compool Relay

[Dagobah]

I'm upgrading from a 1-speed to a 2-speed Whisperflo today. I also need to add a relay to my compool to make the 2-speed work with the automation system.

-The 1-speed has 2 black wires and a ground, but the 2-speed 3 terminals and a ground. Not sure which wires go where.
-On the relay, I can tell where the small maroon plug on the relay goes into the board on the left, but unsure about where to wire the two red wires.

 

[JasonLion]

For a two speed pump you need four wires between the pump and the controller: ground, common, high, and low.

Ground remains connected to the ground bar in the panel, and the other end goes to the green ground screw on the pump.

The common hot wire is one of the two hots wires, the one that does not go to the new two speed relay. It gets connected to connection #1 at the pump.

The other hot wire from the old pump relay runs to the new two speed relay common connection. Then both high and low speed wires run from that relay to the pump. High speed connects to #2 at the pump. Low speed connects to #3 at the pump.

 

[Dagobah]

For a two speed pump you need four wires between the pump and the controller: ground, common, high, and low.

Ground remains connected to the ground bar in the panel, and the other end goes to the green ground screw on the pump.

The common hot wire is one of the two hots wires, the one that does not go to the new two speed relay. It gets connected to connection #1 at the pump.

The other hot wire from the old pump relay runs to the new two speed relay common connection. Then both high and low speed wires run from that relay to the pump. High speed connects to #2 at the pump. Low speed connects to #3 at the pump.

I'm still a little confused. Looking at the relay, the left side has one wire leading off, the rest are attached to the relay. Right side has three open terminals and one wire leading off that connects to a black wire on the left.

Ground is easy, it just connects to the ground screw on the pump.

It sounds like I'll need to add a new 4th wire.

But I'm unclear on where these wires from the pump enter the 2-speed relay, and where these two wires leading off the relay attach to.

 

[JasonLion]

There are currently two hot wires coming out of your existing pump relay. One of those runs to the common connection on the pump, the other runs to the "Common" connection on the relay (the black wire coming out of the relay).

One thing to watch out for, there are two unrelated connections being called "common". One on the pump. The other on the relay. They are actually the two different hot wires coming out of the existing pump relay.


Another possibly confusing point: you will end up with two pump relays. The old one turns the pump on and off, the new one changes speeds.

Also, the thin wire currently coiled up against the relay gets uncoiled and plugs into the controller circuit board (somewhere, not sure where they want it to go, probably mentioned in their manual).

 

[Dagobah]

I asked a EE friend of mine when all this started, he suggests:

-I remove the two gray wires going into the existing relay
-I place the two wires leading off the new relay into the slots on the existing relay where I just removed the two gray wires.
-I place the two black wires into the high and common slots of the new relay
-I run a new wire and plug it into common.
-I plug the coiled wire into the 2-spd slot on the board
-On the pump, common goes to #1, high goes to #2, and low goes to #2.

Is this correct?

 

[JasonLion]

That sounds more or less right.

I'm not sure which "gray" wires you are referring to. The wires removed from the old pump power connections should be the same ones connected to the new relay's terminal block. They appear to be called both gray and black in the above list.

Also, low goes to #3 on the pump, not #2 (which you list twice).

One tricky part, there are two black wires currently running to the pump. You need to be able to distinguish them from each other. You can either do this with a continuity meter, or by trial and error. That is to say, if you use them for high and low, there is some chance that high and low will end up switched, which you could then correct later.

 

[Dagobah]

Well, I got it wired up. Easier than it sounds. Due to the location of the pump, I was pretty much doing a handstand while wiring it.

Pump started, but it started raining before I could get it primed or check the low/high speed. When I turned the pump off, the relay sparked and tripped the breaker. Something must be wrong.

 

[Dagobah]

Rain stopped. Went out and double checked the wiring. Everything looked good. Started it up again, and it ran and stopped without issue this time. I think the rain may have been an issue before.

However, 2-speed isn't working, and my plumbing appears to be leaking. At this point, just going to see if the pool company will come out.

 

[Dagobah]

The pool guy just left. He fixed my leak, but the wiring stumped him. Said he doesn't see many Whisperflo 2-speeds. Apparently all the pool builders in my area use another brand. He's sending another guy out tomorrow who should be more familiar. But said he thought my wiring was correct, which is why he was confused. (Which does make me feel a little better!)

 

[Dagobah]

Thought I'd give an update. Second pool guy came out. He thinks the motor is a candidate for replacement, so it's going back. When he walked up said it smelled like burning rubber, not a good sign. Also pointed out the 2-speed switch cover was dented, which is how it arrived. This will be the third motor I've had to send back due to shipping damage from Amazon

He wasn't able to figure out the wiring. Said he's never installed a whisperflo 2-speed on a compool and he's been in the business since 2002. Said 1-speed or variables are far more popular in this area. He suggested the 2-speeds don't move as much water, so you have to run them longer to turnover the pool 2x a day. Said the variables usually pay for themselves in a year and the motors are better built.

At this point I might just have him install a 1-speed whisperflo so I can get this running again.

 

[JasonLion]

Variable speed pumps have significantly worse reliability than two speeds, at least so far. Hopefully they will eventually learn how to make them more reliable, but they haven't yet.

 

[wktexas]

After all these years since 2014 and all the Pentair 2-speed Whisperflo pumps being sold, this thread is the only advice thru the whole global internet that explains exactly how to wire the relay as well as wire the pump. Every pool professional must use this thread because no one at Pentair would know how to explain it.