Jandy JXi (260) heater - insufficient flow rate

MostlyCanuck · Sep 7, 2021

Hi there

Brand new heater on new pool build. Heater is supposed to function with min flow rate of 30GPM. However, in my case, it needs ~45GPM to fire up and any speed below that heater does not kick in and shows "check flow" error message.

I find this very frustrating because I have invested in VSF pump to run pool low and slow and dial in the min flow required to optimize filtration/circulation and minimize spend....aka what I learned from this site! My PB dismissed it by saying that that's just what "the manual" states and there can be variance.... I find the variance too great to be acceptable in this case.

Two questions:
- Anyone experienced similar circumstances and is there a known fix (something in the heater to adjust to let it see the full flow coming in)?
- Could this be due to piping setup? My PB didnt have too much room on equipment pad and pipes to the heater have three 90-degree elbows right before heater... and I thought maybe all the 90s are restricting the flow?? Is there such thing?

Thank you!

ajw22 · Sep 7, 2021

MostlyCanuck said:
Hi there

Brand new heater on new pool build. Heater is supposed to function with min flow rate of 30GPM. However, in my case, it needs ~45GPM to fire up and any speed below that heater does not kick in and shows "check flow" error message.

How are you measuring the flow rate? What the pump displays is a mathematical approximation and not measuring actual flow rate.

What RPM does your heater require?

I need to run my Pentair MasterTemp heater at 1700 rpm as my minimum flow rate for the heater and SWG to be happy. I have never even looked at what flow rate the pump says that is.

MostlyCanuck said:
I find this very frustrating because I have invested in VSF pump to run pool low and slow and dial in the min flow required to optimize filtration/circulation and minimize spend....aka what I learned from this site! My PB dismissed it by saying that that's just what "the manual" states and there can be variance.... I find the variance too great to be acceptable in this case.

Without measuring the actual flow you don’t know if you have something to complain about.

MostlyCanuck said:
- Could this be due to piping setup? My PB didnt have too much room on equipment pad and pipes to the heater have three 90-degree elbows right before heater... and I thought maybe all the 90s are restricting the flow?? Is there such thing?

No, a few 90's will not make a difference.

Is your equipment pad significantly above or below the water level?

Post pics of your equipment pad.

MostlyCanuck · Sep 8, 2021

I am pretty confident about flow rate measurements as I am getting it both via Intelliflo VSF/Intellicenter as well as a second indepndent reading from a FlowVis flow meter and the two are pretty close within small margin.

Based on manual, there are no RPM requirements for the heater - just a min (30) and max (100) flow rate.

Pad is level with pool (a few inches higher).

Attached are pix of the equipment pad.

Most grateful for any suggestion you all can share.

Cheers
L

ajw22 · Sep 8, 2021

That Jandy heater have the integrated Versaflo bypass?

I think that is the way that heater is. I doubt Jandy will say there is any problem.

PoolGate · Sep 8, 2021

I agree with your builder. Run your heater at a setting that it is happy with. I kind of wish they would stop advertising any sort of flow rates it only leads to confusion. I am sure builders wish it too!

MostlyCanuck · Sep 8, 2021

ajw22 said:
That Jandy heater have the integrated Versaflo bypass?

I think that is the way that heater is. I doubt Jandy will say there is any problem.

I dont know what the Versaflo does, but mine doesn't have it. That series of heaters now (can) come with it based on marketing material I read, but mine didn't as far as I can tell.

MostlyCanuck · Oct 7, 2021

To close the loop on this - and for the benefit of anyone encountering the same issue: I fixed the problem.

Despite the band-aid solution my PB was suggesting, no, you don't need to run the pump at 3000RPM to achieve enough flow with this heater, and yes a heater like this rated for 30GPM should work at that flow.

I called Jandy/Zodiak and they sent a tech. The tech replaced two parts. A pressure valve (I could be getting the name wrong), which he mentioned comes standard for 5PSI and he replaced with one for 2PSI. That got rid of the "check flow" error at lower water flows. Then he replaced the unitherm governor which was somehow clogged with gunk and that got rid of this annoying howling/whaling noise the heater was making.

G-knows what's next, but for now, with these two adjustments to the hardware, the heater runs exactly as needed and very quiet.

Hope this helps anyone else with this heater experiencing similar symptoms.

ps0303 · Oct 8, 2021

No your heater does not have the versaflo. The versaflo is very recognizable when looking at the exterior of the unit.

The thermal regulator might have been gunked up as you have a new pool and the pool finish is still curing.

Poolbreh · Oct 9, 2021

Are you only getting 45gpm at 3000rpms?
Yea you can change the pressure switch. Will it potentially heat up and cause leaks and gaskets to leak because the output is 125f? Probably. I think the point everyone is trying to make is there is a fine line. Most people don’t run the heater continuously so the savings on electricity wouldn’t compare to the damage it may cause messing with the pressure switch. If someone runs their heater 12 months out of the year this may be a good idea. But otherwise the argument is pointless IMO. The benefits running it at higher rate and lower rate it’s based on each circumstance. Flow rate more often than not is the symptom of someone having a heater issue. So it’s best to run at a rpm rate healthy for the heater.