I was looking at the wrong model.
The 8550 has 9 psi head loss (20.79 feet) at 30 GPM.
That is a crazy amount of head loss.
You might need a 10 psi spring check valve bypass.
It is the same bypass.
Contact Raypak and ask them if the head loss data is accurate.
Raypak Pool & Spa, Residential and Commercial Hydronic Products -
www.raypak.com
The problem is that the heat exchanger is a spiral titanium tube inside the larger tube.
This is not designed for the type of flow a pool has.
They need to increase the diameter of the inner and outer tubes.
This will not reduce the efficiency of the heat transfer.
It would actually improve the heat exchange efficiency.
It's the same mistake that they make with the gas heater and using multiple passes instead of a single pass.
Increased contact time seems like it should be better because the water gets hotter, but that reduces transfer efficiency.
For the hot side, you want to extract as much heat as possible, which means that the hot fluid gets cold.
For the colder pool water side, you want to minimize the temperature increase because there is always water moving through the system.
In other words, 100 gallons gaining 1 degree is more efficient than 10 gallons gaining 9.5 degrees.
It all goes into the main body of water either way.
What pump do you have?
If it is variable speed, what speed are you using?
What was the filter pressure before the heat pump was installed?
What is the filter pressure now?
Can you show the system>
ITEM IS BRAND NEW ONLY OPENED BOX TO SHOW EXACTLY WHAT YOU’RE PURCHASING WORKS ON RHEEM HEATPUMP POOL HEATERS NO RETURNS FOR ANY REASON AS ITEM IS BRAND NEW FROM FACTORY, ANY ISSUES JUST CONTACT ME I SHIP EXTREMELY FAST ALWAYS SAME DAY ANY QUESTIONS JUST ASK AND I WILL ANSWER ASAP!
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Titanium Heat Exchanger for Pool Spa, Heat or Cool, Rheem/Raypak (H000369) 8450
