The power usage is consistent with the 1.5 HP model.
What is the pump P/N part number from the barcode sticker?
What HP is on the motor label?
NEW Raypak Heat Pump Heater significant flow restriction?
- Thread starter hotpool2468
- Start date
What is the pump P/N part number from the barcode sticker?
What HP is on the motor label?
it uses more electricity if I run it at the same speed on bypass. Not sure why the difference. It pulls ~2kw on bypass at max.
I also have been suspicious of a suction side air leak….the pump basket often has 3 inches of air in it… it goes away at higher speeds.
2.8 times more restrictive? Could the check valve be a factor? That is the only difference besides a slightly longer loop and a few elbows.
Power usage depends on flow and system head loss.
The flow is higher at lower head loss, so it uses more power.
The pressure reading on my filter was ~30 psi at 45gpm with heater. So that checks.Your system curve with the heater is really bad at about y = 0.03669 X^2.
The heater is about H = 0.00924F^2.
So, the system without the heater would be about H = 0.02745F^2.
At 45 GPM without the heater, the system pressure would be about 24 psi.
With the heater, the system pressure will go to about 33 psi.
Curve A: H = 0.0167 x F2 (Curve 2.0)
Curve B: H = 0.050 x F2 (Curve 1.5)
Curve C: H = 0.0082 x F2 (Curve 2.5)
Where: H is the total system head in feet of water.
F is the flow rate in gallons per minute (gpm)
How to Read Pump & System Curves
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y=0.03669X^2, y from 0 to 75 - Wolfram|Alpha
Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels.www.wolframalpha.com
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Seems to be excessively restrictive.
See what Raypak has to say about the restriction.
Maybe some sort of blockage?
The check valve should be relatively minor.
What exact check valve do you have?
7305: 2"–2½" 180° NeverLube® Check Valve (2" Flow).
The first is H = 0.05F^2, which makes it about curve B.
The first is H = 0.015F^2, which makes it about curve A.
That puts the Heat Pump at about H = 0.035F^2. (56 feet or 24 psi)
The heat pump should be about H = 0.013F^2.
That makes the heat pump about 2.7 times more restrictive than it should be.
The heat pump is causing about an extra 24 psi, when is should be about 9 psi.
The heat pump is causing 15 psi more than expected.
30 psi - 24 psi = 6 psi filter pressure when bypass open.
6 psi + 9 psi = 15 psi expected when the bypass is closed and flow is going to the heater.
The first is H = 0.015F^2, which makes it about curve A.
That puts the Heat Pump at about H = 0.035F^2. (56 feet or 24 psi)
The heat pump should be about H = 0.013F^2.
That makes the heat pump about 2.7 times more restrictive than it should be.
The heat pump is causing about an extra 24 psi, when is should be about 9 psi.
The heat pump is causing 15 psi more than expected.
30 psi - 24 psi = 6 psi filter pressure when bypass open.
6 psi + 9 psi = 15 psi expected when the bypass is closed and flow is going to the heater.
The check valve should only create about 0.43 psi at 40 gpm.
Maybe a clog in the heat pump lines?
Maybe a clog in the heat pump lines?
Check valve is Hayward Check Valve PSCV2S2 2 - 2.5 Inch.
The filter pressure is 15psi with bypass open at 45gpm.
The filter pressure is 15psi with bypass open at 45gpm.
The head loss should be less than 1 psi.
The heater is creating about an extra 15 psi and it should be about 10 psi with the check valve.
15 psi with the bypass open is pretty high for 45 GPM.
Which suction and return valves are open?
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So, 15 psi at 45 GPM with the bypass open and 30 psi at 45 GPM with the bypass closed?
That's a 15 psi jump, where the expected increase is about 10 psi, so about 1.5 times more than expected.
The 15 psi is high for a flow rate of 45 gpm.
The pressure should be closer to about 5 to 8 psi with the bypass open and about 15 to 18 with the bypass closed.
That's a 15 psi jump, where the expected increase is about 10 psi, so about 1.5 times more than expected.
The 15 psi is high for a flow rate of 45 gpm.
The pressure should be closer to about 5 to 8 psi with the bypass open and about 15 to 18 with the bypass closed.
Check the cell to see if it is clean.
What does each return valve go to?
Why is there a check valve on the suction?
Check the pump basket to make sure that it is clean.
When was the last time you backwashed the filter?
What does each return valve go to?
Why is there a check valve on the suction?
Check the pump basket to make sure that it is clean.
When was the last time you backwashed the filter?
Cell was cleaned last week, filter backwashed 3 weeks ago. Pump basket is clean. But those are all common to the bypass and the heater. Check valve on suction? No idea i didn’t install the pump. Pool has bubble jets and regular jets on the return the others that are off are slide and deck jets.
Three weeks is a long time for that size filter.
What is the clean pressure?
Time to backwash again and note the pressure before and after the backwash at the same flow rate.
Was the cell clean?
I would remove the flapper in the suction check valve unless you really need a check valve there.
What is the pump elevation relative to the pool?
I would put a check valve between the pump and filter.
@JamesW i have the same setup, with a similar equip pad. I’ll post a pic tomorrow.
What do you think the solution is here? Bypass the HP, except when needed, and move on?
What do you think the solution is here? Bypass the HP, except when needed, and move on?