Boiler fill line question

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jcco

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Hi all,
New DIYer here looking for advice. This looks like an awesome resource.
I am needing to replace my boiler fill valve. It is a glycol system separated by a Watts 9d-M3 backflow preventer from my domestic water. I was going to replace the fill valve and backflow preventer, but researching the 9D-M3, it does not meet code for that application(says not for lines with glycol). Not sure if that is new or it was never installed to code. The 9D-M3 also does not meet the current lead-free standard. I think I have 3 options. Install new 9D-M3 and fill valve and get on with life.
2. Install a new double check valve on the system as it sits
3. Switch the 9D-M3 and fill valve to the irrigation side of my domestic water which already has a double-check valve in it. I worry about the surging on the irrigation side, but not sure if I should be. Just curious if anyone has any suggestions. Thanks in advance!
 
jcco said:
Hi all,
New DIYer here looking for advice. This looks like an awesome resource.
I am needing to replace my boiler fill valve. It is a glycol system separated by a Watts 9d-M3 backflow preventer from my domestic water. I was going to replace the fill valve and backflow preventer, but researching the 9D-M3, it does not meet code for that application(says not for lines with glycol). Not sure if that is new or it was never installed to code. The 9D-M3 also does not meet the current lead-free standard. I think I have 3 options. Install new 9D-M3 and fill valve and get on with life.
2. Install a new double check valve on the system as it sits
3. Switch the 9D-M3 and fill valve to the irrigation side of my domestic water which already has a double-check valve in it. I worry about the surging on the irrigation side, but not sure if I should be. Just curious if anyone has any suggestions. Thanks in advance!
Click to expand...
you cant do #3 you have to keep those two non potable systems totally separate …...if your code says its not for use on glycol systems you would need an Reduced Pressure Zone backflow preventer (rpz) has to be a testable device with an intermediate relief valve...(this dumps water in back siphonage or back pressure conditions) and I would install a spring loaded check valve with a foot of the back flow device this prevents the check valves from catering/and dumping water do to quick opening valves....your washing machine.....I install them on every device I install
 
Geofd said:
you cant do #3 you have to keep those two non potable systems totally separate …...if your code says its not for use on glycol systems you would need an Reduced Pressure Zone backflow preventer (rpz) has to be a testable device with an intermediate relief valve...(this dumps water in back siphonage or back pressure conditions) and I would install a spring loaded check valve with a foot of the back flow device on the house side.. this prevents the check valves from catering/and dumping water do to quick opening valves....your washing machine.....I install them on every device I install
Click to expand...
 
As Geofd stated...it has to be a Reduced Pressure Zone Backflow Preventer due to the fact that it's a glycol system, which is classified as a HIGH Hazard(or Health Hazard).
A double check valve assembly, is a testable device but is not acceptable for glycol.
I believe some jurisdictions may allow a manual fill, which cannot be hard piped. In other words, not physically/permanently connected.
Massachusetts is definitely not one of them!
The only other approved method is an Air Gap. But in order to use an air gap system in an application that requires it to be pressurized, a pump must be included. Not practical for small applications but absolutely the best protection against cross connection.
 
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Thanks @Geofd and @Diehard! Exactly what I needed to know. Never even thought about it, but now that I'm learning about it, I don't like the way this is set up. Hopefully I haven't been drinking Glycol for the last 10 years. Definitely want to fix it right. I'll get me a RPZ backflow preventer, a check valve, and the new fill valve I already have. Better late than never to get it fixed up. Thanks Again!
One final question. Does a typical backflow preventer need to be under pressure to work? I have a valve before my current 9D-M3 that i can close off and basically separate the systems there until I can get this done, but I don't want to make the backflow preventer not work. Thanks!!!
 
Pretty sure it will still do what it's suppose to do. But I wouldn't hesitate calling Watts or emailing them on your questions.
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jcco said:
Thanks @Geofd and @Diehard! Exactly what I needed to know. Never even thought about it, but now that I'm learning about it, I don't like the way this is set up. Hopefully I haven't been drinking Glycol for the last 10 years. Definitely want to fix it right. I'll get me a RPZ backflow preventer, a check valve, and the new fill valve I already have. Better late than never to get it fixed up. Thanks Again!
One final question. Does a typical backflow preventer need to be under pressure to work? I have a valve before my current 9D-M3 that i can close off and basically separate the systems there until I can get this done, but I don't want to make the backflow preventer not work. Thanks!!!
Click to expand...
that's what the back flow will do...once the city water passes thru the back flow the check valves and relief valve prevent the potable and non potable water from mixing so there is no need to keep the valve closed
 
I believe the concern is with the existing Watts 9d-M3 unit and the fact that it's still a risk no matter how remote the possibility is.
Granted, all the necessary conditions would have to be met, like a negative pressure on the potable water side and fouled checks valves. The possibility of mixing of the glycol is still present, even with the vent to help prevent it. That would not be possible with the valve closed.
 
Right @Geofd and right @Diehard. The 9D-M3 backflow preventer, if working properly(and hopefully has been) should keep the systems separate. With a leaking fill valve, i just figured I would just shut it off on both sides. I've had the glycol side off since the fill valve started leaking and have not lost any pressure out of my boiler. My original plan was to just replace the fill valve and BFP in kind, but when I received the new 9D-M3, it had the not lead free "not for use in systems in contact with household potable water" warning. That's when I started researching all of this. I guess the 9D-M3 was probably once considered fine for this use, but from your responses there are more code compliant, if not better options. It also states in the literature "not for us in glycol systems". Love seeing that on something I've been using for my glycol system 10+ years. Might as well do upgrade while it needs fixing. Thanks again!
 
If a boiler fill valve has to be lead-free, that is taking the code too far. Yes it is connected to the potable water system, but the water flows from the potable side to the boiler, so if there is any lead in the valve, it would leach into the boiler, and never back into the potable side where someone might drink it.
 
I was thinking along the same lines. I suppose there's a remote chance of getting a little of that water, that sits on the potable water side, back into house piping. But I feel it's overkill, myself.
Every soldered connection in my house has lead in it. What should I do? Replace it all.;)
 
fixitron said:
If a boiler fill valve has to be lead-free, that is taking the code too far. Yes it is connected to the potable water system, but the water flows from the potable side to the boiler, so if there is any lead in the valve, it would leach into the boiler, and never back into the potable side where someone might drink it.
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I guess I sort of agree that it is an overabundance of concern, but the water on the potable side would be in contact with the fitting. When water is not flowing, any leached lead can still move around in the water especially as it starts and stops when the water is turned on and off. I'm sure it's a very small amount, but it was deemed a risk enough to require lead free fittings on any fitting in contact with a potable water system a few years back. I don't know. That 9D-M3 has 2 strikes against it as far as code compliance. It's not compliant for health hazard systems and it's not lead free. I'll get it replaced with a current Lead free RPZ BF preventer and I'll live forever! Here's what I think I need once I get over the sticker shock!
 

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I wasn't going to mention this, but as you may or may not know, many, if not all states(don't know if it applies in all states), require periodic testing of an RPZ, by a certified tester. In my state it's annually. The water department is required to log it and track it. Used to be in the neighborhood of $125-150 per test around here.
 
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I used to test for a company in mass I tested and surveyed all over the boston area unless your backflow is permitted and registered with the water dept it wont get tested
we never tested residental devices...I think the reseasoning is that the homeowner would never let you in....I ran into this testing and surveying commercial establishments
we did have the righ to shut off their water if they refused but that never happened.....its just like having a testable device for your irrigation....they are never tested
 
Geofd said:
I used to test for a company in mass I tested and surveyed all over the boston area unless your backflow is permitted and registered with the water dept it wont get tested
we never tested residental devices...I think the reseasoning is that the homeowner would never let you in....I ran into this testing and surveying commercial establishments
we did have the righ to shut off their water if they refused but that never happened.....its just like having a testable device for your irrigation....they are never tested
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That's good information Geofd. As I believe you know, I was a certified tester in Mass as well. But I never tested any.:D
I thought it was the plumbers responsibility to notify the appropriate jurisdiction. But that's another story.
 
I doubt they have it together around here enough to keep up with it, but it's possible and good to know. I do have one on my irrigation system and I've never had it tested, though it was in there when I moved in. I'll look and see if it has any old inspection tags on it, but I don't think it does.
 
jcco said:
I doubt they have it together around here enough to keep up with it, but it's possible and good to know. I do have one on my irrigation system and I've never had it tested, though it was in there when I moved in. I'll look and see if it has any old inspection tags on it, but I don't think it does.
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in mass there are no inspection tags....just records at the water dept that it was tested
 
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