Mineral Deposits In Household Pipes

[Dan O]

replying to jamesgangnc, Dan O wrote: Actually I can tell you that deposits can and do build up in copper. Years ago I replace a water heater with an indirect water heater. I was horrified to see that after only a few years (3-5 or so) the hot water pipe output from the heater had maybe half of its cross section left open. In general, folks may be right that it isn't usually a problem with copper. However, in my case I think my situation was worse due to the fact that I have a passive hot water re-circulation loop. So the water lazily flows through the loop 24/7 - I assume continually depositing calcium. Recently I added a softener for the hot water feed. As a side note, we are on a township well with medium hard water. I don't recall the number but remember looking it up an it wasn't considered extremely hard.

[Ed Pawlowski]

Water sits in the hot water tank and the minerals collect over time. In your case, they were circulated more than normal. Water heaters are notorius for mineral buildup.

[TimR]

I don't know the exact chemistry of it but if you get hot water too hot, mi nerals precipitate out. We've had that problem with boilers at work. If w e set the temperature too high, or it got out of control, mixing valves etc would start failing in a day. I would think that temperature is hotter th an domestic hot water tanks but maybe there's some effect at a lower temper ature.

[Ed Pawlowski]

Your boilers at work should be blown down on a regular basis and possibly have chemical treatment. I used to do a test every day on our steam boilers as we used a lot of water. Even though softened you still have to be careful with steam boilers. We operated at 110 psi, over 300 degrees.

[James Wilkinson Sword]

Why don't cars suffer from this? Can't we make boilers run like car cooling systems?

[Taxed and Spent]

You get new water all the time, bringing in more and more minerals.

[James Wilkinson Sword]

I see.

Since you're here, explain why (older?) Renaults got airlocks all the time and simply stopped pumping water without warning, overheating the engine to catastrophic failure. Central heating does the same, but most non-Renault cars never get airlocks. Surely they could learn from each other.

[Taxed and Spent]

I retrofitted an old Renault with some left over Trane parts, and it worked just fine.

[Ed Pawlowski]

Sure, depends on the system. Steam used for process is constantly adding make up water. We used 250 to 400 gallons an hour depending on production load. These were 125 hp boilers running high pressure and we had to have a state licensed person on staff any time they were running.

Boilers in industrial setups have plenty of places for loss in the system too if you have many meters of piping. Smaller residential boilers usually don't see those problems.

In another section of the building we had a steam heating boiler and it needed very little care and no chemicals. Makeup water was minimal and it was low pressure (>15 psi) so no license needed.

[Ed Pawlowski]

French engineering. Wine and brie anyone?

[TimR]

The boilers were okay. The boiler had a loop for the building heating syst em and a loop for domestic hot water. It was domestic hot water that would precipitate deposits in the valves if it got too hot. Obviously you can't do chemical treatment on domestic hot water.

[Ed Pawlowski]

A softener would help.

[TimR]

system and a loop for domestic hot water. It was domestic hot water that w ould precipitate deposits in the valves if it got too hot. Obviously you c an't do chemical treatment on domestic hot water.

Sure. But it would be costly to run in a building this big, with 300 showe rs.

[Ed Pawlowski]

Pay me now or pay me later. What is the cost going to be clearing the pipes of 300 showers? How well do the shower heads work? Dishwashers? Softeners cost little to operate once installed. I bought 50# bags of salt for about $9 delivered in volume. We treated enough for up to 400 gallons and hour. We did it to save money!

[Unquestionably Confused]

What will it cost to repipe that big building when the pipes begin to look like your milk drinking, high cholesterol and fat loving uncle Eddie's arteries at age 59 when he goes into full arrest? ;-)

[marsie]

Yeah, but it tastes GOOD!

[TimR]

g system and a loop for domestic hot water. It was domestic hot water that would precipitate deposits in the valves if it got too hot. Obviously you can't do chemical treatment on domestic hot water.

Or you can just keep the water cool enough, which is what we do. Works fin e.

The mixing valve right after the storage tank will scale up if we get the h eat up too much. The rest of the pipes don't seem to have any problem.

Maybe I should mention we have 410 buildings on this campus. Softeners wou ld cost a lot to run, and it comes out of the maintenance budget.

[James Wilkinson Sword]

Cheaper to turn it off and tell people to wear jumpers.

[Frank]

My neighbor said he just took his softener off line because he had leaky pipes. His pipes are PEX but leaks were at fittings.

Softening will not take much out of water, just exchange calcium for sodium.

Take a bowl of water somewhere and let it evaporate and you'll see all the salts left behind. I have crusts around pots of indoor plants because of mineral build-up. Does not bother the plants.