- Apr 26, 2009
- 419
OK, not yet, but I'm about to....
This is a customer's pool - not my design, just something I've been working (dealing) with the customer for almost a year... The previous owner "home built" the pool (~17,000gal), and should have found TFP first.
All of the plumbing is 1.5", skimmers on one line, MD on another, T'ed to 2" at the pad to the pump. Return is 1.5". Pump is 2HP WhisperFlo, valve off to Polaris PB4. I know... worthless without pictures...
Filter (DE) pressure averages around 32psi clean, to 38 dirty - system is currently clean. And to really make things difficult, the whole pad is about 8' below the pool - so you have to shut-off ball valves to work at anything at the pad - or get deluged with water.
I know the pump's wayyyyyy over-sized for the pipe, and have discussed with the customer he'd be much better off changing out the pump... He doesn't have the funds right now.
Note: Using the 2.31xPSI indicates the TDH is around 90 (suction+pressure), which says the WFE shouldn't have any flow moving through the system(via the head curve). I can indeed say that there's plenty of water coming out both returns... including the sweep when the PB4 is running.
The issue that continually comes up is that right after my customer moved in, he purchased and had a Heat Pump installed (not by, or from me). It worked for a while - he was keeping it on year-around... But within a few months of being installed, it started giving an "HP3" alarm.
HP is the alarm given on the "AC" compressor: "Compressor High Pressure", and the system shuts down after three tries of starting up (hence, "HP3" flashing on the unit) and needs power-cycled to re-start.
The vendor (Rolm Industries) was swearing it was the flow switch. It's a standard binary flow-switch: Flow = closed, 0 ohms. No flow = open, infinite ohms. They sent a flow switch and asked me to install it (and paid me for it). I opened up the unit, and ohmed-out the existing flow switch. Pump on = 0 ohms. Pump off = infinite. Left the pump on. A few minutes of trying to start up, the thing goes HP, HP, HP3 and turns off. Still zero ohms on the flow switch. I took the new flow switch, taped it "closed" and wired it in (prior to cutting any pipe) and still got the HP3.
Fortunately, the system had a circuit diagram on it and I located the "HP" switch - it's on the AC-side of everything. AC ain't my bailey-wick (what does that mean, anyway...), but I'm smart enough to be able to ohm-out the HP switch and verify that it's open (infinite ohms, should be closed = zero ohms) when the system was trying to start up and the pump was on.
Stick with me... this is in "Pumping Station" (and not "Everything Else") for a reason.
So, the vendor calls up an AC guy, and the AC guy comes out and this guy "fixes" the unit by swapping out the pressure-switch on the AC side of things. The unit works great for a few months... then starts going "HP3" again.
My customer calls the vendor, vendor says we're not getting enough flow through the system... deja-vous? I tell the customer that there's no way that there's not enough flow (minimum flow for the switch to engage is 20GPM).
Then, the vendor says that because the pad is ~8' below the pool, that the extra pressure/head because of the distance the pump needs to push the water up is causing the HP (remember, the HP isn't in the flow of the water at all, it is part of the freon's circulation path). "Hello? Water drops 8' before it rises 8' - system is sealed both to and from the pool..."
Now, the vendor says they finally got it. There's too much flow through the water side of the unit - their system is rated for max 70GPM, and now they want me to put in a flow-bypass on the system.
The customer sent me the installation manual tonight, and it does indeed recommend a bypass when water is flowing >70GPM... I am just very skeptical that when I re-plumb (and charge the vendor) that this is going to work... While getting paid is nice, I want to do right by "my" customer.
So, given the details, does the last statement make any sense? IDTS, but wanted to bounce it off of others first. And, if I install the bypass, without a flow-meter on the heat-pump side, exactly how will I know how much water's going through the bypass vs. through the heat-pump? Schlock, I say...
Thanks.
- Jeff
This is a customer's pool - not my design, just something I've been working (dealing) with the customer for almost a year... The previous owner "home built" the pool (~17,000gal), and should have found TFP first.
All of the plumbing is 1.5", skimmers on one line, MD on another, T'ed to 2" at the pad to the pump. Return is 1.5". Pump is 2HP WhisperFlo, valve off to Polaris PB4. I know... worthless without pictures...
Filter (DE) pressure averages around 32psi clean, to 38 dirty - system is currently clean. And to really make things difficult, the whole pad is about 8' below the pool - so you have to shut-off ball valves to work at anything at the pad - or get deluged with water.
I know the pump's wayyyyyy over-sized for the pipe, and have discussed with the customer he'd be much better off changing out the pump... He doesn't have the funds right now.
Note: Using the 2.31xPSI indicates the TDH is around 90 (suction+pressure), which says the WFE shouldn't have any flow moving through the system(via the head curve). I can indeed say that there's plenty of water coming out both returns... including the sweep when the PB4 is running.
The issue that continually comes up is that right after my customer moved in, he purchased and had a Heat Pump installed (not by, or from me). It worked for a while - he was keeping it on year-around... But within a few months of being installed, it started giving an "HP3" alarm.
HP is the alarm given on the "AC" compressor: "Compressor High Pressure", and the system shuts down after three tries of starting up (hence, "HP3" flashing on the unit) and needs power-cycled to re-start.
The vendor (Rolm Industries) was swearing it was the flow switch. It's a standard binary flow-switch: Flow = closed, 0 ohms. No flow = open, infinite ohms. They sent a flow switch and asked me to install it (and paid me for it). I opened up the unit, and ohmed-out the existing flow switch. Pump on = 0 ohms. Pump off = infinite. Left the pump on. A few minutes of trying to start up, the thing goes HP, HP, HP3 and turns off. Still zero ohms on the flow switch. I took the new flow switch, taped it "closed" and wired it in (prior to cutting any pipe) and still got the HP3.
Fortunately, the system had a circuit diagram on it and I located the "HP" switch - it's on the AC-side of everything. AC ain't my bailey-wick (what does that mean, anyway...), but I'm smart enough to be able to ohm-out the HP switch and verify that it's open (infinite ohms, should be closed = zero ohms) when the system was trying to start up and the pump was on.
Stick with me... this is in "Pumping Station" (and not "Everything Else") for a reason.
So, the vendor calls up an AC guy, and the AC guy comes out and this guy "fixes" the unit by swapping out the pressure-switch on the AC side of things. The unit works great for a few months... then starts going "HP3" again.
My customer calls the vendor, vendor says we're not getting enough flow through the system... deja-vous? I tell the customer that there's no way that there's not enough flow (minimum flow for the switch to engage is 20GPM).
Then, the vendor says that because the pad is ~8' below the pool, that the extra pressure/head because of the distance the pump needs to push the water up is causing the HP (remember, the HP isn't in the flow of the water at all, it is part of the freon's circulation path). "Hello? Water drops 8' before it rises 8' - system is sealed both to and from the pool..."
Now, the vendor says they finally got it. There's too much flow through the water side of the unit - their system is rated for max 70GPM, and now they want me to put in a flow-bypass on the system.
The customer sent me the installation manual tonight, and it does indeed recommend a bypass when water is flowing >70GPM... I am just very skeptical that when I re-plumb (and charge the vendor) that this is going to work... While getting paid is nice, I want to do right by "my" customer.
So, given the details, does the last statement make any sense? IDTS, but wanted to bounce it off of others first. And, if I install the bypass, without a flow-meter on the heat-pump side, exactly how will I know how much water's going through the bypass vs. through the heat-pump? Schlock, I say...
Thanks.
- Jeff