Hi folks –

Does anyone know if acidic well water can cause pinhole leaks or other destruction in hydronic heating systems? The reason I ask is because my well water ph is very low – 5.5. I’m in the process of figuring out how to take care of this, but I’ve been mainly thinking that the main problem is the effect of that water on my copper piping.

Don’t know why I didn’t think of it before but it just occurred to me, that’s the same water that feeds into my boiler and heat piping and radiators. Seems to me failure of that equipment would make pinhole leaks in my copper piping seem like a minor problem in comparison. I’ve heard people say you can always replace copper piping in the house with PVC if you water is too acidic. But seems to me with hydronic heat, you have no choice- you have to bring the water ph level up or you would probably eventually have leaks in your heating system. Is that correct?

Any thoughts would be greatly appreciated!

 

For steel and cast iron equipment you want to be neutral or slightly above. You can do some water treatment to change the PH.

 

Thanks rbeck!

I kind of figured I’d better treat the water to get the PH higher. I was just entertaining the idea of just replacing the copper piping in my house with pvc. Seems like there would be a lot of advantages going that route. My house isn’t big and I can do it. But I figured that still would leave a big problem with my heating system. My boiler is steel - and I guess my piping is iron? Guess I’ll bite the bullet and get that ph up to neutral or slightly higher as you say. Thanks for your input.

 

If you are otherwise satisfied, or not concerned, about your acid water then replacing your domestic plumbing with CPVC and chemically treating the heating system is certainly a viable option.

I would strongly suggest a "reduced pressure backflow protector" rather than the more common double check valve type normally installed on residential heating systems. You can use any of a number of common chemicals to raise the pH of the heating system water. It would be necessary to install some kind of "feeder" to the system and it would also be necessary to periodically check the pH of the heating system water. If all you do is raise the pH then you can get test tape from a pool/spa supply store.

BTW, your piping is steel if it isn't copper. Iron piping went out of use about 100 years ago. What is commonly called "black iron" is really steel.

 

Thanks furd.

Believe I understand what you are saying. Sounds like a good possible route. I have in fact been learning about feeder systems. But I was using in the box thinking before – either feed the entire house or nothing. Didn’t like the effect on the drinking water. I see now there are ways around that.

But If I understand then, the reduced pressure backflow protector would be used because it would better protect the rest of the plumbing system from backflow from the heating system, which would be especially important if you use a feeder for the heating system?

I just looked at my system to see if I have a check valve but I can’t find one. I probably don’t know what I’m looking at, but all I have on the cold water feed line to the boiler is a Watts Regulator which has stamped on it “Set 12-15”. And if I remember from what I learned on this forum in the past, that regulator reduces the house pressure down to a lower pressure for the boiler? But does that take the place of a check valve or should I really have one regardless of what else I do? Or would that only be necessary with a feeder system? I found some other problems with the plumbing so I don’t assume anything is correct.

Thanks for your time and information.

 

I see you are in Southeastern PA, welcome to the land of water so acidic it could be used for battery acid. What we are using here is a tank of crushed limestone to neutralize the water. There is a fiberglass tank about 5' tall, 12" in diameter, dip tube to the bottom, basket on the bottom, then a cap that has the water entering the top and then out from the dip tube.

From time to time it needs a back flush to re-set the bed along with adding more crushed limestone (calcite). This just takes a few ball valves and some added piping. The tank goes between the well's pressure tank and the household water.

Now, it does make the water harder as it adds minerals. But it sure beats the bitter acid taste.

I'm not keen on using plastic for house hold plumbing on a well system. It allows a biofilm to build up that copper won't. This biofilm habours bacteria. Maybe OK on city water with the chlorine in it.

Anyway, by using the neutralizer I don't worry about the hydronic system. Make up water is not added that often, and when it is it isn't a lot. This summer I need to open & drain the boiler & pipes for some repair work.

I am thinking of refilling with distilled water instead of the well water. One reason is the minerals of the treated house hold water. Don't want it to precipitate out in the boiler. The distilled water is free as the basement dehumidifier produces some 2 to 3 gallons a day in the summer.

This would need to be pumped in, but that too is rather easy. Just use a sealed container and 15 psi of compressed air. Right into the boiler drain with a piece of washing machine hose.

Al.

 

Hi Al –

Thanks for responding neighbor. Coincidence you should mention bitter acid taste. I’ve been using bottled water for a long time now till I get my water treated and tested again. Today I ran out of bottled water and made coffee with the well water for the first time in a long time. You are certainly right about a bitter acid taste. I think it tastes like battery acid. I still have the taste in my mouth tonight. Added minerals would certainly be better than that taste.

Good point about city water with the chlorine in it. I grew up in Philly and the chlorine taste turned me off drinking water as a matter of life-long habit. Too bad! But I guess it was good protection. I see what you are saying about the plastic pipes and well water.

Doesn’t sound like the added hardness is a problem for you. I guess that means you didn’t have to add a softener? I heard sometimes people need one after a neutralizer.

Sounds like you don’t feel the back flush and adding limestone is frequent enough to be a nuisance. That sounds very good. (Been getting into the various types of neutralizers on another forum.) But does that mean you manually backwash your neutralizer? Wouldn’t bother me unless you had to do it every day.

That is a neat idea with the distilled water. I was going to wait until warm weather to see what kind of water is in my heating system (I’m afraid to look) and how to change it if needed. Figured I’d be asking on this forum in the summer. I have some humidifiers I could put in my basement.

I was wondering about the rate of make up water in a hydronic system? One of many things that puzzles me – where oh where does that water go?

Thanks again Al!

 

Don't use distilled water. Real distilled water, made by boiling and collection of condensate, can have a pH <6.

Use deionized or demineralized water.

 

A softener would make the water better by removing some of the hardness. From what we can tell it isn't required on this system. No problem with soaps or dish washing (by machine or hand) or showering and so on.

The back wash is done manually. It is built into the set up with added pipes and ball valves. A line is run over to the laundry tub with a garden hose threaded end soldered on (up at the ceiling). I place a bucket in the tub and a hose from the fitting into the bucket. This is to catch any media that escapes the tank (don't want it in the drain).

Then back flush for a few minutes. Return the valves to the proper position, remove the hose and dump the bucket of water. The small amount of media that escapes I usually let dry and toss it in the trash.

For re-filling I do this about every 6 months. I was checking it monthly but found that it didn't use that much.

Make up in the hydronic system, sometimes I wonder. Some of it is from using a non-bladder expansion tank. The air in the tank dissolves into the water. This lowers the pressure and more water gets added.

Al.

 

Thanks for your input xiphias!

And thanks Al for your time. Sounds like the manual backwash works well. I had seen systems advertised where they said you only needed to backwash a few minutes when you do it if your system is sized right. Looks like your system is a case in point.

And I see where many people say there is a good chance you won’t need a softener after your neutralizer. Again, looks like your system is a case in point.

Re-filling every 6 months sounds great! My case might be more often since I have a pretty low ph (5.5), but still, I bet in any case it would be many months between re-fills.

Alas the mystery solved – I believe I also have a non-bladder expansion tank. Now I won't be ransacking the house looking for the missing water.

Thanks again!