Reliable check-valve for in-line chlorinator.

[WorBry]

I'm looking at purchasing an in-line chlorinator for my AGP. I know many on this forum don't favor chlorine pucks in general (CYA levels etc), but I used them all last season (my first), in the skimmer basket, without any problems. Just got fed up having to remove and replace the pucks when the pump was run discontinuously. Plus, I wanted a solution for vacations. A neighbour said he'd used his chlorinator (Hayward) for ten years and recommended them.

The two brands I'm considering, due to local availability, are Hayward and Olympic (WaterPik/Jandy) - the Olympic is around $40 cheaper here. Looking at the product information, both recommend putting a check-valve (one-way) between the filter (or heater, which I don't have) and chlorinator, to prevent back-flow of chlorine. The neighbour's set-up doesn't include one, but it does seem a wise precaution, especially if the chlorinator is fitted directly to the filter valve return port.

Can anyone recommend a reliable (mechanically), corrosion-resistant check-valve? I can imagine if the valve corrodes, or worse, clogs, there would be problems. I would be using quick-connect unions to connect the chlorinator-check-valve combo to the filter return port and the chlorinator to the return line (flexible hose), so that the unit can be removed at winter closure, and should problems arise.

Another thing I was wondering. I'll be putting the pump on timer this year, at least early and late season. Is it OK to leave the chlorine feed (dial control) valve open (apart from when refreshing the pucks) or will this result in chlorine/gas build up when the water is not flowing. Having to close manually the valve every time the pump goes off would clearly defeat the object.

 

[jblizzle]

I think the recommended check valves are the flapper type by Jandy or Pentair. Low head loss clear top so you can see ot working and they are rebuildable if a problem develops.

 

[WorBry]

Hi,

I assume this is the type you are referring to:

http://www.backyardpoolsuperstore.com/J ... _4467.html

Quite pricey !

I've seen less-expensive check-valves, specifically designated for chlorinators, on Amazon:

http://www.amazon.com/Rainbow-Chlorinat ... 055&sr=1-1

http://www.amazon.com/Hayward-CLX220EA- ... 430&sr=1-2

Are they no good?

Edit: Looking at the manual for the Hayward CL100/200 (in-line) and CL110/220 (offline) chlorinators, I think that maybe the third valve linked above is an integral component of the off-line chlorinators that prevents back-flow from the return through the feed line into the chlorinator when servicing. Looks like the in-line CL100 (but not CL-200) uses something similar inside the unit.

The Pentair/Rainbow spring check valve (second link) would certainly fit the bill.

http://www.inyopools.com/Products/03900020003548.htm

but it is a sealed unit, and I do like the fact that the Jandy check valve (also 'highly resistant to chlorine') can be inspected and accessed for maintenance.


Just thinking though. I was anyway intending to fit a ball stop-valve in the return line. If I were to drop the chlorinator to ground level and fit two stop valves, one either side of the chlorinator (so it can be isolated when recharging), would a check-valve still be needed? Edit: thinking about it more - as long as the pool water level (return jet) is higher than the filter return port (as it is in my case), there will always be potential for chlorine to migrate back to the filter head when the pump goes off, irrespective of the position of the chlorinator.

 

[jblizzle]

The first link is what I was talking about... although that is double the price of other online sources I gave seen.

I do not know about plumbing for chlorinators. Just know the clear check valves are less restrictive and repairable.

 

[WorBry]

The first link is what I was talking about... although that is double the price of other online sources I gave seen.

I'll search some more. Actually that link was for the 2.5-3" fitting model. The 1.5-2" version is:

http://www.backyardpoolsuperstore.com/J ... _4468.html

Just called a local pool store. Told me that, whilst awaiting stock of fittings for the new season, they were not aware of the need for a check-valve with chlorinators, as, during the cooler periods (early and late season), when one might consider running the pump discontinuously, the pucks dissolve far too slowly to allow build up and back-flow of chlorine. He just recommended installing a ball stop-valve to isolate when recharging/servicing. Strange, when the manufacturers specifically recommend installing a check valve.

Just checked, and the pucks I have been using in the skimmer are the 3" slow-dissolving type,

 

[jblizzle]

Still seems a bit high for cost but I don't know what you need for you application.

Note the small number is the pipe size that fits into the valve and the large number is the pipe size that matches the valve and requires a coupler.

 

[WorBry]

It would be the 1.5"/2" size.

 

[WorBry]

OK, so what I thought was going to be a relatively simple exercise is becoming rather confusing and complicated (possibly over-complicated).

Went to another pool store to see what they had. This was one of the big pool chains in my locale (Quebec), who do a lot of installations.

Explained my requirements and the response was, again, why on earth would I want to put a check valve between the chlorinator and filter? Because the manufacturer recommends it. Nah, just fit the chlorinator straight to the filter port, maybe with a short bit of spacer pipe and/or union quick-connect, if needs be. That's what everyone does. If you want to fit a check-valve, fit it after the chlorinator in place of a stop-valve - that way you don't have to worry about closing another valve when opening the chlorinator. Pretty much what the other pool store said.

The 'standard' 1.5-2" check-valve (20 $CAN + tax) they stocked (not sure of the brand) is a spring type that looked similar to the Pentair/Rainbow one, maybe a bit bigger, with slot-in (solvent weld) connects. This one though, could be unscrewed for cleaning (although not for replacing the spring) whereas the Rainbow valve is sealed. The spring strength (1/2 pound) was also less than the Rainbow valve (2 pound), but he told me that was adequate.

He showed me what fittings it would take to fit the check-valve between the chlorinator and filter port. Adding to this, the chlorinator (Olympic model - width 10", including 1.5" adapters) and elbow quick-union for connecting the return hose, the whole assembly would be about 26" long, all hanging on the filter port. I do have about 6' between my return and filter (local regulations), but no way would that would be practical without some additional support. What about piping the chlorinator to ground level? He didn't recommend it - would require a stop-valve on either side of the chlorinator, and the vessel would always be full to the brim when opening. Plus, I'd still need some ground support.

They did have the Jandy 180 1.5-2" check-valve on one of their show-room demo pools (for a purifier unit I think), and could order one (61 $CAN + tax), but I'd only gain a few inches.

So, what to do? Follow the pack and forget the check-valve or follow the manufacturers recommendations.

I did come across this online manual for a Waterway in-line chlorinator, that indicates the type of equipment that should be protected, quote:

If your pool has any of the following equipment, install a corrosion-resistant
swing check valve:
• Brass or bronze gate, rotary or backwash valves.
• The preceding valves constructed of PVC or other plastic material with metallic shafts.
• Filters, heaters, heat exchanges or other items with metallic tanks, shafts, coils or tubes.

Does the multi-port head on a Hayward sand filter have any metallic components this would apply to?

What do other AGP users on this forum with in-line chlorinators do? Are off-line chlorinators a better solution in this case?

Unfortunately, I don't have any pics of my existing set-up just now.

 

[WorBry]

Well, after reading around, I think I'll go ahead and fit a check-valve between the filter and (port-mounted) chlorinator. Regardless of what the pool store experts say. I cannot believe that, when the pump is off, acidic chlorine will not accumulate in that segment of the line and filter head, even in cooler weather, and especially if the pool return is higher than the filter port.

One of the main reasons for installing a chlorinator is so that I can leave the pool running when on vacation, without having to impose on neighbours etc - and what if the power goes off and/or GFCI trips when on vacation? I'd prefer just having a green pool to deal with.

I guess a lot depends on how 'corrosion-resistant' the check-valve is itself. I'll maybe try one of the locally available spring-type valves first and see how it holds-up in the early part of the season when the pump is on timer.

Just a thought, about vacations. Are there any large/high-capacity (like 9-10 3" pucks) chlorine floaters out there? I guess one could be rigged together with 4" PVC pipe, end stops (one screw-in) and maybe a flange so that it can be held in a styrofoam float. Drill holes with a sliding collar for 'feed' control. Maybe vent at the top. Some screen mesh inside to stop blockage and bits floating out. Secure it with cord. Remove gingerly on return.

What do BBB enthusiasts do when they go away?

 

[WorBry]

Change of mind Whilst looking looking for a seller for the Pentair/Rainbow "chlorine-resistant" spring check-valve, I managed to speak to a Pentair guy, who affirmed, and explained why, a check-valve is not needed, even when the in-line chlorinator is fitted directly to the filter port and the pump is running discontinuously on timer. Only needed if there is an in-line heater. In fact he advised against putting a check valve any where in the system (e.g. in place of a stop valve on the return) unless absolutely necessary, as they slow down the flow and can fail.

And so concludes the distinctly uninteresting subject of chlorinator check valves :blah:

 

[75th]

ATTENTION: For anyone reading this thread, the above is certainly not true. Due to experience, I know for a fact that without a (YES) restrictive check valve (or a plumbed in P-trap) to separate your in-line chlorine dispenser from your filter and/or multi-port valve, WHEN the lines drain out (and they will), extremely corrosive chlorine gas WILL enter your filter housing and EAT anything metal, including stainless hardware, starting with the threads. You'd be surprised at the physical damage. It WILL destroy anything metal in short order due to the insane Cl gas levels that can build up. It can ruin a stainless filter housing (pinholes) or an expensive valve. This is why inline tablet dispensing units are a bad idea in the end, because they can do more harm than good. If you must go with one, the off-line units are somewhat safer, as you can loop the thin lines, effectively creating P-traps, trapping the gas in the unit itself.

 

[Bama Rambler]

75th - - the actual incidence of that happening is extremely low and is very dependant on the individual plumbing.
I'm sorry that you had an issue and would like to know more about your particular setup when this happened.

 

[75th]

Sure Dave. In this instance, the return out of the (wretched Hayward EC-65 perflex) filter (2-3 feet above the ground) was running horizontal out, 90 down to 7" above ground, 90 horizontal, (no check valve in horizontal run), inline Pentair Rainbow and then 90 down straight into underground to pool. Again, no check valve or water column to stop the dispenser gasses from going straight up inside the filter when this line drained out on its own. I'm thinking a "P-trap" made from long curving 2" 90's plumbed between the filter and dispenser unit would be more effective and much less restrictive than a Pentair R172288 check valve (which might not even stay air-tight anyway). What's your opinion on the P-trap? Good idea or not? It's sure to trap the Cl gas between that "P-trap water column" and the pool water level underground. No metal there to eat.

The less desirable alternative would be to 90 up AFTER said tablet dispenser unit, 90 horizontal and 90 down to underground. Together with the line coming down from the filter, this would keep the horizontal run and bottom half of the dispenser unit permanently full of water, which would make maintenance of the unit (they plug inboard of the fitting sometimes and stop dispensing) less than ideal. This water column would eventually be full of super-chlorinated water during shut-off ...and THAT MIGHT lead to the whole chlorine gas thing in the equipment yet again... so back to the P-trap idea.

IMHO the liquid chlorine dispensers are the best way to go, all else being equal. What's your opinion?