Polaris 280 too buoyant?

[jerry100]

I'm having a problem with my Polaris 280.

It seems to be too buoyant. When in operation, it tends to leave the bottom of the pool and swim around in the 'air'. When not in operation, it sits with the rear end off the bottom of the pool. If I take it out and throw it back in the pool, it sinks very slowly.

The result is that it does not do a good job of cleaning the bottom, and almost every day manages to tie itself in a knot around the hose connection at the side of the pool.

Now what this is not:

* Air trapped in the unit. All air is out of the unit.
* Air in the line. I can see it, there's no air going through the line.
* Incorrect settings on the various adjustments and spouts. I've played around with the float, tail pressure, position of the rear propulsion control to no avail. In any case, the problem is evident when the unit is OFF.
* Position of the hose floats. I've played around with this, and there no tension on the floats when the unit is on the bottom of the pool. I can hold the hose under the water while the unit is on the bottom, and it still doesn't have all wheels on the 'ground'.
* The backup device. This is operating normally - no water flow when it's supposed to be between backup cycles.

I've tried adding weights (took it apart and put them inside, hung weights on various appendages, etc.) but mostly this seems to throw the unit out of balance so it will either fall on its side or otherwise malfunction - it does stay on the bottom though.

My last guess is the following: I have a salt water chlorinator, so there's a lot of salt in the water. I think that would make the unit more buoyant. But if so, I would expect to see some chatter on the internet from others with similar problems.

Maybe I'm missing a part, though this is hard to imagine?

Any ideas would be appreciated!

Thanks,

Jerry

 

[DBfan187]

the head float(big white ball on top of cleaner, part #A20) needs adjusted, make it about an 1" or 1.5 finger widths away from the feed pipe.

It's what gives the unit balance.

 

[UnderWaterVanya]

Now what this is not:

* Air trapped in the unit. All air is out of the unit.
* Air in the line. I can see it, there's no air going through the line.
* Incorrect settings on the various adjustments and spouts. I've played around with the float, tail pressure, position of the rear propulsion control to no avail. In any case, the problem is evident when the unit is OFF.
* Position of the hose floats. I've played around with this, and there no tension on the floats when the unit is on the bottom of the pool. I can hold the hose under the water while the unit is on the bottom, and it still doesn't have all wheels on the 'ground'.
* The backup device. This is operating normally - no water flow when it's supposed to be between backup cycles.

the head float(big white ball on top of cleaner, part #A20) needs adjusted, make it about an 1" or 1.5 finger widths away from the feed pipe.

It's what gives the unit balance.

It appears the OP has already tried adusting the float. I'm frankly at a loss. When adding weight - very small amounts added where the float goes would be what I would try. My 380 hasn't ever done this.

OP: How did you test for air trapped inside?

 

[PJ]

I would also like to know the answer to this problem. I have a customer who's Polaris is doing the exact same thing, but it will work for a short time.
This is what we tried:

1) cleaned out the backup valve (it was stuck partially open all the time).
2) Adjusted float, tail, etc...
3) shortened the hose (it was a little long).
4) replaced O ring on main pump, it was sucking air and sending it back through the returns and Polaris line.

Next thing we will do in the spring is open it up and check for blockages in the jets, check the gears...etc... (we are at a loss with this one).

 

[duraleigh]

I don't have a 280 but when my robot floats a bit, it is ALWAYS because air has been trapped.

It comes from the factory heavier than water so it seems the only way to get it lighter than water is to put some air in it.

 

[Christian]

This issue can be caused by water getting inside the head float. If there is any water at all inside the head float it throws off the buoyancy.

 

[UnderWaterVanya]

This issue can be caused by water getting inside the head float. If there is any water at all inside the head float it throws off the buoyancy.

:? How does reducing the bouancy of the float make the entire device float more?

 

[DBfan187]

there should be no water inside of it, if there is then throw it out and put a new one on

 

[Christian]

Vanya water in the head float throws off the buoyancy which can cause the exact symptoms he is describing in the OP. I'm not sure on the exact physics of it I just know I've seen water in the head float cause this issue.

 

[UnderWaterVanya]

Vanya water in the head float throws off the buoyancy which can cause the exact symptoms he is describing in the OP. I'm not sure on the exact physics of it I just know I've seen water in the head float cause this issue.

Funky... I am totally befuddled by that.

 

[jerry100]

Ok folks - thanks for all the responses. I found the problem - a pool sweep version of a 'kidney stone':

There are two small vertical water jet spouts on the interior of the central shaft that apparently serve 2 purposes: Obviously, to cause a stream of water upward that will suck up debris into the bag, but also to cause downward pressure on the whole unit to keep it more or less rolling on the bottom of the pool.

In my case, it turns out that one or more tiny pebbles had become trapped inside the plastic housing that routes the water to one or both of these jet spouts. When the unit was in operation, the pressure of the water would trap the pebbles up against the small opening of the spout(s), blocking the water flow. When the unit was off, these were just about impossible to diagnose because without the water pressure, then would simply fall back down the (internal) piping.

Credit to my wife: removing the water-directing plastic housing and shaking it, you could hear the pebble(s) knocking around.

It was difficult to remove the pebble(s) because just blowing on the spouts wasn't quite enough - the air pressure wasn't adequate to move the pebbles all the way back up their route and get them out. But a combination of blowing and turning the unit in various orientations eventually caused the pebbles to emerge.

Quite a puzzle. The pool sweep is now working perfectly.

I hope this helps other poor souls with floating sweeps!

Jerry

 

[DBfan187]

take the 2 screws off the bottom cover, then also remove the 2 screws holding the jet onto the frame, then rinse/poke out the debris in the jets, then put it all back together

 

[tpn7399]

Ok folks - thanks for all the responses. I found the problem - a pool sweep version of a 'kidney stone':

There are two small vertical water jet spouts on the interior of the central shaft that apparently serve 2 purposes: Obviously, to cause a stream of water upward that will suck up debris into the bag, but also to cause downward pressure on the whole unit to keep it more or less rolling on the bottom of the pool.

In my case, it turns out that one or more tiny pebbles had become trapped inside the plastic housing that routes the water to one or both of these jet spouts. When the unit was in operation, the pressure of the water would trap the pebbles up against the small opening of the spout(s), blocking the water flow. When the unit was off, these were just about impossible to diagnose because without the water pressure, then would simply fall back down the (internal) piping.

Credit to my wife: removing the water-directing plastic housing and shaking it, you could hear the pebble(s) knocking around.

It was difficult to remove the pebble(s) because just blowing on the spouts wasn't quite enough - the air pressure wasn't adequate to move the pebbles all the way back up their route and get them out. But a combination of blowing and turning the unit in various orientations eventually caused the pebbles to emerge.

Quite a puzzle. The pool sweep is now working perfectly.

I hope this helps other poor souls with floating sweeps!

Jerry

Hi, I have this problem and have checked for the “kidney stone”...it’s clear. What else have you all tried?

Ball float has no water in it and is .75 inches from the post.

Not sure what else I can do. Thanks in advance....

 

[Pool Clown]

Hi, I have this problem and have checked for the “kidney stone”...it’s clear. What else have you all tried?

Ball float has no water in it and is .75 inches from the post.

Not sure what else I can do. Thanks in advance....

Make sure that the wall fitting with the finger screen in it, or the inline finger screen is clear. Also make sure that the booster pump is putting out plenty of pressure. The wall fitting has a pressure relief valve that should always be bleeding some water off when the pump (booster) is running.

 

[Mayorb]

Water in the head float will cause the cleaner to lay on its side. Every time.
Floating is caused by trapped air, defective back-up valve or clogged vacuum jets.

 

[1TM]

Troubleshooting the polaris pool cleaner too buoyant (solved).

My Polaris pool vacuum cleaner (380) was also lifting off the pool floor, flying in mid-air, wiggling around, doing wheelies, running on its side and otherwise moving odd.
I finally found the solution which was as difficult as overclocking a computer (and perhaps with more parameters to tune). It was the thrust jet.

What I checked first:
The three vacuuming jets in the cleaner were not plugged with little pebbles (had this happen several years ago), water wasn't leaking (much) from the hose, pool filter was clean, backpressure valve at pool wall working (recently replaced), strainer in the backpressure valve clean, none of the internal hoses disconnected inside the cleaner (had that also happen a few years ago). The float (the oval shaped) was not broken and had no water inside, was 1 inch from cleaner.
Cleaner acted as if the flow is too much, wiggling like a firehose.
Running it on just cleaner pump or cleaner and pool pump made no difference.

What did help the most:
The rear thrust jet was too strong. I disconnected and opened the cleaner, and inserted half of a plastic screw fastener inside the thrust jet to act as a flow restrictor to make it less powerful of a jet, and to divert more flow to the three vacuuming jets.

What also helped:
Half of the hose also was replaced. My cleaner is well over 10 years old and the hose has become much less flexible, especially now in cold January water (we don't stop pools in Texas for the winter). This semi-rigid hose made the cleaner run on its side, but did not explain the wiggling when the hose was fully extended. After I replaced the hose (before I fixed the rear jet) it would still fly up and wiggle.

What did not help:
adjusting the jet to 3, 5, 7, 11 o'clock positions as various posts recommend.
replacing the reverse valve (it did leak a little water)
running both pool pump and cleaner pump

My current configuration:
Cleaner runs only with the cleaner pump; the pool pump is off.
Jet is aimed at 10 o'clock, not at extreme but half-way outward.
Sweeper hose screw is open 1 turn (fully closed then open 1 full turn).
Hose configuration: the cleaner connected to a ~20 inches soft (new) hose, backup valve, another 20 inches old (harder) hose with a float, a swivel, followed by 8 feet of new soft hose with several floats, a swivel, 8 feet of old (harder) hose with few floats, a swivel and 2 feet of soft hose to the pool wall.
Made sure there is no air suction in pipework: checked and tightened all connections around the cleaner pump, pool heater and pool pump. Actually removed and bypassed the pool heater for now as it corroded and was leaking/sucking air, which made the cleaner pump lose and regain suction and the pool hose would jerk from time to time when the cleaner was running.


The thrust jet part itself is only a year old and came with a polaris (OEM) rebuild kit. Perhaps the new plastic is softer than what it used to be and got eroded making the jet opening too wide and the jet flow way too strong.

 

[millerwd]

Thanks for this post! A plugged jet was plaguing my Polaris for months. A plugged jet was the culprit. I forgot how quickly the Polaris cleans the pool when everything is working correctly.

 

[Jadamz]

STIFF OLD HOSE.
I found my culprit.
The hose was stiff and had some curled sections were too stiff for the robot to straighten, or to stiff for it to bend as required.

Instead of buying new Polaris hose, I opted for plain 3/4-inch (2cm) garden hose. That's the fatter one than the typical.

Used hose click-in fittings etc.

All good now, but the hose is green instead of white.