Ever hear of an air switch occasionally self-activating?

[nuttyp]

Hello all - I'm trying to help some friends who have been plagued by a spa air switch that seems to self activate from time to time. I'm wondering if anyone has heard of that before. Their pool is a 10K gal IG gunite, spa alongside using the main 240V pool pump and 240V blower, controlled by an intermatic RC2343PT four position air controlled relay switch with timer, spa air switch installed on top ledge of spa, 30 ft of 1/8" flexible (aquarium style) clear tubing from switch to RC2343PT.

In order for the timer portion of rc2343 to properly control the pool pump when spa is not in use, the RC2343 must be in "Step 1" (of it's 4 possible steps - wherein subsequent presses of the air switch advances the internal RC2343 relays to create 4 possible combinations of pump and blower on and off). Again Step 1 leaves the pump controlled by the timer. This works fine for awhile, but something is causing the rc2343 to advance to other steps, sporadically, once or twice per week, as if something or someone pressed the spa-side air switch.

Going back 2 years, I believe they had a similar symptom and they had the RC2343 replaced. Then one year ago they had the tubing replaced. They have no kids, they're away and pool cage is locked, and the pool cleaning service swears they never touch the spa-side switch, yet it keeps happening. Each time I go over there I find the relays in a different step, and of course the timer cannot control the pump properly if the controller is in any of steps 2, 3 or 4. Today I went over and replaced the RC2343PT (again, which was probably stupid but I had observed the enclosure had issues anyway and the tubing compression nut was missing).

Now I have to go over there again because the new RC2343PT has new issues, so I'll return it for refund if possible (brand new and the blower relay is intermittent and somehow they assembled the timer tripper switch to go ON with red stepper and off with green, which is backwards - ugh). I'm tempted to re-install the last RC2343PT after fixing the enclosure and finding a compression nut for the air hose, but then I'll be back to where I was, with the original problem.

I don't have a good feel for the air switch model, have not tried to remove it - it's just a white covered rubber plunger at the top, no clicking or anything when depressed, but one hint is that it takes very little pressure to actuate the controller into the next "step". Perhaps about 1/2 inch of plunger travel causes it to actuate. I'm wondering if anyone has heard of the "heat of the day" adding enough pressure in the hose to actuate the switch. This is south florida. Another hint is that despite the fact the hose was a fairly snug (might say very snug) fit on the old RC2343, absent the compression nut the hose was found disconnected a couple times in the past year.

On the next trip over I'm going to try blowing out the hose to see if water / condensate might be in the hose. Or perhaps a wider hose that is less sensitive? Or a switch that is less sensitive? Perhaps a better controller? I'm looking at the Len Gordon FF1094TC-4 as one possibility if I can't trust the relays in the RC2343PT. Any advice on good controllers of this type (short of a $3K automation system)?

The friends are out of town for a few months, so in the interim I shut off the blower breaker so it can't come on when in the wrong step, and I'm monitoring the pump remotely using an old smartphone set to auto-answer video calls from my skype account - a clever little free "baby monitor" I though of and folks have posted about around the web - lol.

Thanks for any advice!

JT (nuttyp)

 

[OldPoolMan]

I have on 3 occasions seen phantom air switches tripping. 2 were do to moisture in the tubing. The third was unknown but we solved it by adapting a larger diameter air tubing.

 

[ps0303]

Water in the airline. Air switches are notorious for this problem.

 

[nuttyp]

Thanks very much guys for the replies, I'll especially chase the water in the air line angle!

 

[JamesW]

Any chance that a spa cover is pushing the switch?

 

[ps0303]

Thanks very much guys for the replies, I'll especially chase the water in the air line angle!

Use some compressed air to blow it out. It's just a common annoyance with air lines.

 

[nuttyp]

Thanks again for the ideas. No spa cover there, but a clever thought! I blew air through the 35 ft of 1/8 tubing today, no water came through but I may need to try a compressor that is better than my 1 gal cheapo. Also need a helper there to watch if "anything" is really coming through - resistance to air flow seemed very high. Then again 35' of 1/8 tubing should pose resistance. I also noticed that although there may not be water in the tubing, the 1" conduit the tubing routes through is FULL of water. That too will take a better compressor methinks, so more to experiment with. For now I leave tubing disconnected from control so timer operates reliably.

 

[abalosa]

Thanks again for the ideas. No spa cover there, but a clever thought! I blew air through the 35 ft of 1/8 tubing today, no water came through but I may need to try a compressor that is better than my 1 gal cheapo. Also need a helper there to watch if "anything" is really coming through - resistance to air flow seemed very high. Then again 35' of 1/8 tubing should pose resistance. I also noticed that although there may not be water in the tubing, the 1" conduit the tubing routes through is FULL of water. That too will take a better compressor methinks, so more to experiment with. For now I leave tubing disconnected from control so timer operates reliably.

Hi nuttyp, after much searching online I finally found your discussion about the same problem I am having. Every once in a while, i come home and the pump is running. I can tell it was the air switch because the control is at a different step as you described.

Have you found a solution? I have replaced the tubing, i rerouted it to avoid sun exposure ( in case it was heat build up causing air in the tube to expand) and nothing worked. i disconnected the tubing from the control for now. My next attempt will be to replace the electrical air-activated switch in the controller in case it is too sensitive.

 

[wjr75]

My indoor whirlpool had one that would turn on once in a while. It finally turned on one day when I was not at home and burnt the pump out. Once they replaced the pump never had the problem again. I guess the switch was bad.

 

[nuttyp]

I know this is an old thread but a couple folks reported the same problem - in this thread and in email - so I thought I would update the topic with a couple fixes I deployed. I also encountered this same problem on another RC2343PT, although with a different failure mode. In the original case the RC2343 sensor was overly sensitive, and in the second case I bought a pool home (as luck would have it with the same setup) and it's not sensitive enough. At this new place it seems the prior owner abandoned the spa-side remote plunger and installed a wall mounted and larger air plunger near the RC2343 on the equipment wall. That switch works, but any switch 40 feet away with 1/8 tubing will not actuate the stepper.

Let me digress for a moment about the cause of these failures. Some in the forum and elsewhere have suggested moisture is the enemy of these air switches. Although I never found air in the 1/8 tubing at either location, both locations had a fair amount of water in the 1" conduit through which the tubing runs. It seems plausible that when the conduit is full of water, condensation into the tubing may be more likely. And it generally just seems best to keep water out of the entire equation, so I suggest making sure water is blown out of the tubing and the conduit - and it may be best just to install new dry tubing. Also install the spa-side switch so it's properly sealed to prevent water incursion into the conduit. And same at the other end, ensure the tubing exits the conduit in a way such that rainwater cannot enter the conduit. I directed the conduit downward with a 45 degree elbow, capped it and drilled a hole just large enough for the tubing. The last turn, elbow and cap are not glued, to allow future maintenance.

Okay, now that water is eliminated for the future, on to my first solution at the friend's house. This one is somewhat of a hack.... I created a sort of "poor man's adjustable air chamber" - basically following the idea from 'OldPoolMan' (thank you OPM) wherein he indicated he once solved the problem with larger diameter tubing. A good idea but I didn't want to buy and adapt and pull that tubing while being unsure what size to get in order to achieve the desired pressure sensitivity. And who knows how long that would work. And I don't want to keep buying and installing new air switches even if the manufacturer is willing to ship only the new air sensor/switch. So I simply took a one gallon plastic jug and glue-sealed a 1/8 inlet and outlet into the cap. Really l I just ran the hose lines through holes in the cap and sealed them with silicone sealant. When the jug is empty, the chamber was too big and would not actuate, so I filled it with water until just the point where a solid hit of the plunger actuated the switch. That wound up being with the 1 gallon jug about 3/4 full, so I effectively created an air chamber about the size of a 3" cube, somewhere between a pint and a quart - but adjustable! Given the aforementioned issues with water one might think this a bit stupid. I initially wanted to just determine the size of the air chamber I needed, but I wound up leaving it that way and it's been working for three years. I don't even think my pal every replaced the water in the jug. So that was the Rube Goldberg fix.

As noted my new place has an RC2343 (why me?) that is not sensitive enough. I chose to remove the air sensor component from the RC2343, ran it's wires out a sealed connector (using proper outdoor 120/250 volt cord) and over to a sealed 4" enclosure which houses an adjustable and easily replaceable air switch that you can get for about $12. Inside the new enclosure I taped the following explanation for any interested party - that note follows below and perhaps answers most other questions. Downside is that I suppose my RC2343 is no longer UL approved (if it ever was).

Questions welcome.

Enclosure note:
The adjacent Intermatic RC2343PT is the pump timer and blower control. The RC2343 has a long history of problems with the air switch sensitivity, both here and in other installations. At times the sensor in the RC2343 is too sensitive and invites false triggers (resulting in the blower turning on and/or the pump turning off) and at other times it fails to respond to the remote spa-side air plunger. As a better solution, this air switch - a Cleveland Controls NS2-0000-05 adjustable air switch - is installed in this enclosure. The NS2 offers several adjustable setpoint ranges, and in this case the most sensitive (black) spring is used. The NS2 contacts are wired over to the RC2343 in place of the integral air switch to actuate the four-step sequencer. The NS2 adjustment screw (on the rear of the NS2) is set to an approximate midpoint. Full instructions and NS2 parts are enclosed.

Note the NS2 adjustment screw is turned clockwise (tightening it) to decrease sensitivity, resulting in more input pressure required to actuate switch. Follow manufacturer's instructions carefully by turning the screw inward until the first labeled NO condition occurs (NO opens to create the default state). At that point positive pressure on P1 closes the NO terminal. More tightening should result in more pressure required to close the NO terminal ("decreased sensitivity"). This is all somewhat counterintuitive - if the default state is not created as described (eg no spring installed or screw loose), all operation will reverse (NO becomes NC and positive pressure on P2 would be required to actuate switch).