RPZ Backflow Prevention Device

[ARedetzke]

Anybody know anything about RPZ Backflow Prevention Devices? We have one on our boiler here at work. It was due for testing, so I called our HVAC company to come out and test it. It failed, the tech tried cleaning it, and it failed again. This device was installed new EXACTLY 1 year ago today. They haven't gotten back to me, but I just know they're going to fight me on replacing this. I know they are a lot more complex than a regular backflow prevention device, and therefore more prone to failure, but one year?? Come on! So my question is what kind of life can I expect out of this thing? Cost me $500 to get it put in last year, and there is no way I'm going to replace it every year. Any advice is appreciated, I'm trying to do my homework before the HVAC company calls me back to try and screw me.

TIA

AJ

 

[NPloysa]

Have the state come do an inspection, then they can possibly prove it's broken and have the boiler company come fix it.



Our backflow preventer on our cold water line for the flash-tank for the steam boiler blowdown leaks like crazy. I told the inspector to write it up so these guys here would actually see it needed to be fixed, instead of blaming us for spending too much money on the HVAC system.



Nick

 

[phloop]

These things are easy to rebuild, they just look complicated. If it fails, the tester should repair it and test it again. I guess some tester's might not be able to repair the device and will need too have a plumber repair it. And unless parts for the device are available, they will have to be ordered in. And if your devices are leaking, they might be doing their job.

 

[Elite1]

Can you give us some more info... what size is it? 1",2",3",4" or bigger? which brand is it? Febco, Watts, Wilkens are the devices I have installed. I am a landscape contractor and install these devices on almost every job. I don't service them, but I do have a buddy who does. He has given me a few pointers over the years. I use Febco more than any other and the most common size that I use is 2". The most common problem is a little debris, sand, gravel or other grit in the springs. Most units have double check valves (ball valves or gate valves) you can shut those down and take apart the spring housing and clean it out with water. When putting it back together put a little liquid dish soap on the gaskets or O-rings it will help them not to crack. If the springs aren't the problem it may just be a leaky o-ring or gasket or a spring doesn't have enough tension.

Who knows, maybe your backflow preventer is fine, but you just got a dishonest tech. looking to make some extra cash.

 

[ARedetzke]

They ended of taking care of it, but the tech's description doesn't make sense to me. I told him I wanted to make sure it was tested before a years service was up to make sure that it wasn't defective before the warranty was up. His response bothered me. Keep in mind that this is actually a company that I trust, they do all my work (and have for years) and have always been fair with me. I'm no plumber, but also know my way around most stuff that they work on. He told me that the RPZ may have just needed a seal kit, and the reason that it didn't test was that it was doing it's job (so it locked up to prevent a back flow, and then was done). So to me, the way he made it sound, these back flow prevention devices are good to prevent one back flow, then they lock up and need to be rebuilt. Now like I said, they more than took care of the situation to my satisfaction, but that sounds like a BS answer to me. I can't believe that these valves are only good to stop one back flow, and then you have to rebuild them. If that was the case, they would have to be inspected more than once a year. Elite, sorry I can't tell you anything else about the valve, I'm out of my area of expertise. I'm happy with the way this was resolved, but I'm worried about possible future incidents. Thanks for all the help guys!!!

AJ

 

[phloop]

AJ. The devices are not a one time back flow situation device. They are good for way more than one incident. Now if it stopped a back flow incident that had enough force behind it, it may have damaged either the disk or seat. That would cause it to leak and not function correctly. Also, his wording of locking up might have thrown you off. That or he doesn't really know what he's talking about. The device doesn't lock up when it works, the check valves inside close. Kinda like a flapper valve for want of an easy discription.



Elite1. You never want to put liquid dish soap on the seal's inside of a backflow device. To do so your introducing a nonpotable liquid into a potable water supply. They sell a compatible lubricant to coat the seals with. It's just a vasiline thats been approved for use in potable water systems. If your buddy is using soap, thats a no-no.



I'm a liscenced backflow tester so I have an idea of what I'm typing here, just so that I don't ruffle any feathers.

 

[ARedetzke]

Thanks for all the help. I'm just going to hope that it tests good for next year. After that we should be in a new facility, with no boiler and no RPZ, thank God!!

AJ

 

[Elite1]

Phloop, you may be right, but the guy who told me to do this, Owns one of the largest backflow testing companies in California. He is also certified and has been doing this work for about 40 years, he has a staff of about a dozen certified plumbers that work for him. Accurate Backflow testing out of Van Nuys... . now I'm sure that there are probably better products, but he did tell me to use this as it is readily available. Besides we are talking about a minute amount of soap, just enough to lube an o-ring etc...

 

[phloop]

Elite 1, He might have been doing this for the last 40 years and might own one of the largest backflow testing companies in California but he is doing it wrong if he is using dish soap inside of a potable water system. Here in Oregon that is a no-no. I've been in the water supply field for the last 13 years myself. That includes installing and operating those water systems from the water supply to the business/home owner.



Ask yourself this, what would you do when you or your company turned on your tap to get a glass of nice cold clean water and got bubbles or foamy water instead? You would call the local water supply company, be it private or a city/municipality and some one like me would have to come out and see why you have nice lemony smelling foamy bubbly water instead of that nice clean clear water you expected. And then we would find that the plumber used dish soap on the inside of a device and would have to go back too him about the problem he had caused.



Sorry about the rant, but dish soap is wrong. If you want something readily available, use vaseline out of a new jar. It is not approved but that is all the approved sealant is. And it will not wash off into the water supply like that soap will do.

 

[Elite1]

Phloop, OK I get your point about dish soap, but to tell you the truth he was suggesting a few drops on your finger tip and rubbing it onto an O-ring that doesn't really make contact with the water supply. But your analogy of someone filling a glass of water and getting soapy smelly water is almost as bad as an analogy of someone pouring a glass of water and having gobs of vaseline in it! In other words neither would actually happen!