I have a 18,000 gallon pool with a spa. I have a Hayward EcoStar VS 2.7hp pump and have been using it for years with a RayPak RP2100 (Model P-R335AL-EN from 1998)
and I was able to run the VS pump at 1000rpm and have 3psi at the filter and have water flowing down from the spa to the pool.
The RayPak was getting pretty rusty on the inside and I've had to replace parts on it over several years, so I knew it was getting old,
but then the heat exchanger started leaking, so I decided I needed a new heater.
Luckily my neighbor was tossing his Pentair Mastertemp 300 from 2013 which he had been using on his 600 gallon hot tub (using bromine incase that matters).
He didnt have any issues with the heater, he just got rid of his hottub so he didnt need it anymore.
So I decided I use the MasterTemp to replace the RayPak and got it all installed, and have been successfully able to heat my hot tub.
However, I have noticed that the water flow is significantly less compared to when the RayPak was install.
Pressure Observations:
Could the MasterTempHeater exchanger be clogged up with Calcium deposits?
Other notes:
and I was able to run the VS pump at 1000rpm and have 3psi at the filter and have water flowing down from the spa to the pool.
The RayPak was getting pretty rusty on the inside and I've had to replace parts on it over several years, so I knew it was getting old,
but then the heat exchanger started leaking, so I decided I needed a new heater.
Luckily my neighbor was tossing his Pentair Mastertemp 300 from 2013 which he had been using on his 600 gallon hot tub (using bromine incase that matters).
He didnt have any issues with the heater, he just got rid of his hottub so he didnt need it anymore.
So I decided I use the MasterTemp to replace the RayPak and got it all installed, and have been successfully able to heat my hot tub.
However, I have noticed that the water flow is significantly less compared to when the RayPak was install.
Pressure Observations:
- I'd say that 2000rpm now is equivalent to 1500rpm previously
- 1000rpm, the filter reads ~0 psi, and it isnt enough to make the hot tub waterfall into the pool anymore, it used to be able to.
- I used to run the pump at 1000rpm 24/7, and that was enough to circulate the pool and hottub. But now its not enough pressure to create flow in the hottub. I have to run at 1500rpm now.
Could the MasterTempHeater exchanger be clogged up with Calcium deposits?
Other notes:
- The pool pump pad is about 3 feet below water level in the pool.
- The RayPak heater exchanger was near water level, versus the MasterTemp heat exchanger is now ~2 feet below water level.
- added 2 new 90 degree 2" PVC elbows get the plumbing to the MasterTemp
- He only used his Hottub about once/twice a month, over the past 6 years.
- There was a rat's nest in the MasterTemp. It was at the bottom, below the heating chamber, and I cleaned it out.
- He used Bromine as sanitizer in his hottub, and I use Chlorine in my pool.
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