boiler feed on or off?

TLM

Ive been installing hydronic heating for 28+ years and have a question for you wallies. Leave the PRV on or off? Ive seen houses flooded because of PRV's coming apart at the seams and seen boilers with no apparent leaks run out of water.... What are your thoughts, if any?

Steamhead

Put a low-water cutoff on the piping above the boiler

and leave the PRV off.

Mark Eatherton

And....

If the home is only occasionally occupied, add a low water pressure cut off, and connect it to either the homes alarm system, or a remote dial out feature.



If the system is brand new, it will take a while to get the free air out of the system, and you will need to keep the makeup on to compensate for the loss. Once it stabilizes, you can cut the make up off, provided that you have a LWCO as Steamhead said.



Belts, suspenders and velcro...



ME

j a_2

agreeed

I as well am a firm believer, leave it off....In fact, that, was discussed in detail here quite some time ago....I also agree leave it open for a few days if you like..As well its my understanding cold non circulating water is the best way to remove air..It is a closed loop system, much like that of a cars cooling system, excuse the analogy,you don't drive around with a hose attached to it...You just check it as required....I also cant quote the page in the IBR guide at this time but it as well recommends keep it closed...30 years installing mainly steam and hot water..and that's my two cents...Oh and I love low water cutiffs, very comforting....to me    j a

Paul Fredricks_3

Not me

Leave it on. I've never seen a house flood because of a feeder. I've seen the basement get wet, but that's usually the expansion tank or relief or coil. I have seen lots of houses get air bound because the feeder was either plugged up or turned off. And they do plug up all the time. Based on the law of averages I always leave it open.

Paul48

Where do you stop?

Where I work....every time someone gets hurt, we wind up with a new rule, and protective device. We're starting to look like football players. Do you shut the main off between showers? The only time I think it would be a good idea, is as said, a home that's only occasionally used. You could spend a fortune trying to "idiot-proof " your home, and still miss something.

Robert O'Brien

Callbacks

If you like going back for free,leave it off

hot_rod

on

Leaving it on is the only way it can do the job you paid it to do.



Put a feeder tank or a water or "feeder" pig instead if you don't want the valve on.



Never been to a problem job caused by an on valve, but plenty of no heat problems, have been reported with new mod cons that have pressure switches, if the fill is off.



"Evolve" is the key word here You'll be hearing a lot of that word.



New boilers equipped with pressure switches may require new fill valve procedures?



hr

billtwocase

gotta agree

The only time I consider leaving the auto feed off, is when the system has antifreeze. Other than that, there are strong arguments for both, but I prefer it on. 

Mark Eatherton

There is a good reason behind my behavior...

And yes, it has to do with an occasional use home in the mountains.



I had a customer up in yonder hills that we;d done a RFH system for. We also installed a Buderi horizontal DHW storage tank below the stairs going to the third level of his home. Whilst still under warranty, a 1" soldered joint decided to start leaking. I am emberassed to say that it was one of my S.J.'s, and upon further inspection, where the manufacturer had stamped the fitting with their name (EPCO), it had attracted the oxides, and I only got a minor face joint cap.



Long story short, the leak did about $30,000 worth of damage. My insurance company fought it tooth and nail, and eventually settled for less than was being asked for. I lost him as a good customer over it, which is sad, but more importantly, the insurance company told us that if we were to continue to be insured by them, that we could no longer have a constant source of water to the heating system. That's when we invented The Pig.



My attitude hasn't changed over the years, and that was about 15 years ago. Truth be known, if there is a leak in the system, regardless of location or source, I WANT to know where it is, because it can not only do structural damage to the house, but with these low content boilers, it will destroy the boiler in short order.



And as Paul Harvey use to say, "Now, you know the REST of the story..... Good Day"



ME

JohnHenry_2

If you build a better idiot trap...

They build a better idiot...



Nothing is truly idiot proof.

Jean-David Beyer

In deciding, do not forget this one.

http://www.heatinghelp.com/article/183/Plumbing-Mechanical-articles/2180/Fill-Valves-Open-or-Closed-August-2011

billtwocase

good reason Mark

Sometimes no matter how hard you try, $hit happens to good people, and I regard you as good people. Some people also take advantage when things like this happen. Everything becomes priceless. 

j a_2

I=B=R GUIDE

In your I=B=R guide on page 3-19 upper left corner is a take on prvs...I remember going over that in my class some years back......there was a mild discussing about them..I do notice that the most common prv in my area at this time is one that has a 15 psi limit I believe.. presently when I do install a condensing boiler the class instructor and the book say the optimal static pressure is 17-18 psig for this particular boiler...So the standard one sold in most supply house boiler trim kits wont work...I think.  Times and so many changes have occurred in our industry over the past few years...Science does not...Now if I can pass the math test below and only press the button once I will be happy...ja

gennady

test

if we build heating system from scratch, we do 2 tests, 1 air test 100psi 2 hrs, then water test 100 psi for 4 hrs. then we leave feeder on. in finished basements or in apartments we offer watts water detection shutoff http://www.watts.com/floodsafe/# as an option for additional fee.

TLM

Thanks

Thanks to all the info. Had always been told/taught to leave the feed on. I have a good friend who lost $$$$$ when he and the family went on a ski trip and came home to find the bottom floor of a split ranch turned into an aquarium from a feeder that came apart at the diaphragm. Now I leave them off. Most of the modcons out there today do have a pressure safety/ lwco of sorts which will protect the small mass boilers. Right?

TLM

Thanks

Thanks to all the info. Had always been told/taught to leave the feed on. I have a good friend who lost $$$$$ when he and the family went on a ski trip and came home to find the bottom floor of a split ranch turned into an aquarium from a feeder that came apart at the diaphragm. Now I leave them off. Most of the modcons out there today do have a pressure safety/ lwco of sorts which will protect the small mass boilers. Right?

Ron Jr._3

Why not leave it to the customer ?

I haven't read the instructions for PRVs in a long time , but I believe some state to leave the valve open and some want it closed .



Why not explain the benefits of both options and if they want the valve left closed ( safest option ) there will be a nominal charge if a zone becomes air bound ? Something that probably won't happen if the valve is left open ......



We leave the valve closed on systems with old radiant or if we see signs the piping looks old and might leak . Too many horror stories from homes with convectors and those crappy wafer bleeders that dry out and leak . Or auto vents that become a water fountain .



Everything else stays open ( we use the AquaSmart on every install ) .