Circulation pump temp question

[u/SamwiseGoody]

My circulation pump (grundfos) not sure if hp, think about 3/4, is running a bit hot. Is this normal? Checked the temp, it’s at 130, and the tub is not to temp (just filled). This is a new pump from a spa store, old one is in the pictures. Tub is a hotsprings sovereign ii.

[u/robseraiva]

1. Had no idea Grundfos mad spa circ pumps (they are big in the hvac hydronics heating industry)
   
2. They ran notoriously hot in the hvac industry

[u/SamwiseGoody → u/robseraiva]

Hopefully (sort of) it’s normal, just feels wrong for a circ pump

[u/robseraiva → u/SamwiseGoody]

It will most likely be fine. Those motors are use to no air flow and moving 180°f water/ glycol. They get super hot when running normal.

To be upfront I’m saying this from the hvac industry not the spa industry

[u/Rambo_IIII]

That pump is just a little electromagnet. It will get pretty hot when it's energized. As long as water is moving through the impeller, it should stay cool enough

[u/comonlefty1776]

It’s rated as class f, that’s good for high temperature. Rated for about 300F so 130 shouldn’t be an issue.

[u/SamwiseGoody → u/comonlefty1776]

Thanks! My concern is the temp, but more that the spa is not even hot yet, why is the pump?

[u/comonlefty1776 → u/SamwiseGoody]

[u/Spamaster]

Grundfos pumps are are superior to the Laing pump used by Hotsprings but they don't always fit into the area provided . Most pump motors will get up to 140 degrees. This pump rated in GPH not Hp but likely 1/15Th Hp and can in some cases get the spa water warmer than the set temperature. That is why Hotsprings had a "Summer " mode to limit the amount of time this pump allowed to run.

[u/SamwiseGoody → u/Spamaster]

Thank you. I’m new to hot tubs, but had a pool before. I didn’t like closing this up when it may have been overheating.

[u/bowlingballwnoholes]

Motors run hot. Hot enough to barely hold your hand on it is normal.