The effects of condensate

Le John

Happy Holidays to all on this site.



Can someone explain how to neutralize condensate from a high efficiency boiler. I am considering a high efficiency combi boiler for a tenant apartment but worried on the effects it will have on the cast iron drain pipes.



A neighbor recently had one put in but the condensate line just drips into a drain. I asked how he neutralizes the condensate but he didn't know so hence the question on this site.



Is draining the condensate straight to a drain acceptable? I don't want to rip out my basement floor to replace corroded pipe. I'll stick to a 85% cast iron boiler and a indirect.



Any assistance is greatly appreciated.

earl burnermann

Condensate Neutralizer

Draining into a pvc drain is fine but not into metal drains.



Here's a link to a condensate neutralizer. Make sure the one you get unscrews so you can change the media. We use these on all the boilers on our campus. When pH readings drops below 6 we dump and refill. Changing the media once a year should be fine for residential use. The tech that figured out how to recharge them uses a piece of screen on the outlet side to keep it from getting clogged by the new media which is plain old pelletized lime that you can get at your home garden store.



http://www.plumbersurplus.com/Prod/Noritz-America-NC-1-Residential-Condensate-Neutralizer-Kit/287915/Cat/143?gclid=CNyijevXzrsCFeHm7AoduC0Auw

Jean-David Beyer

Is draining the condensate straight to a drain acceptable? I

I wondered about this when I (a homeowner) had a mod-con installed. The contractor said the codes where I live in New Jersey are so complicated, and no two inspectors agree, that they would run it outside the house and let it drip on the ground. The theory was that when the inspector failed it, he would specify how it was to be done and they would do what he said. (By the way: no condensate neutralizer.)



Well, that did not work. The inspector could have easily seen the hose from the condensate pump go over to the 1 1/4 inch PVC pipe that went through the outside wall, and walked around to see where it went. But he did not care enough to look, so that is how it still is. It dribbles on the periwinkle plants, and they do not seem to mind it. If it freezes, it does not matter much because there are no walkways there.



The contractor thought he would dig a big hole in the ground, get a big plastic bucket and put holes in it, fill it with rocks, and run the condensate down there. But some inspectors do not allow that.



Some places do not allow the condensate to go into cast iron drain pipe. I understand some do. I have seen it recommended that if you do that, you feed the cast iron pipe downstream from some high water use device, such as a toilet, so the pipe gets rinsed frequently. Urine probably neutralizes it somewhat. I do not know how true this is. For me, I would need a pretty heavy duty condensate pump because I would have to run the tubing up about 10 feet, over about 25 feet, and back down to connect. And since that could not be outside because of freezing risk, and since the house is built on a slab, it would mean chipping away the ceilings (plaster)  of three rooms, and one wall, to run the tubing. This did not appeal to me.

Vinny_5

You can see the difference

in these pictures I posted on this thread. The condensate runs through a neutralizer which is filled with marble chips before it gets pumped up into my drain and down to the septic tank. The condensate leaving the boiler is pretty acidic, but after the neutralizer it is fine.

http://www.heatinghelp.com/forum-thread/142863/Lochinvar-Knight-Wall-Mount-Cleaning#p1276569

Steamfitter66

limestone

3/8 chips in a 2 by 18" pvc pipe.or by one depending on the circumstances.

AlexS

how long...

How long do the marble chips last?  I built a homemade neutralizer for my own system and I see the marble chips have changed color... Does that mean they are spent, or are they still functioning until completely dissolved?



Seems if they're good to go until they dissolve, I wont have to worry about replacement for about a decade...

Jean-David Beyer

How long do the marble chips last?

I do not know. Because I do not know what percentage of a marble chip is calcium carbonate. If you used pure calcium carbonate (calcite is pretty pure), you could let them dissolve away completely. I just looked them up on the Internet, and they are pretty pure calcium carbonate.



But you might still want to replace them sooner. Imagine they dissolve until they are pretty small, and then they get into your condensate pump (assuming the pump is after the neutralizer) damaging the pump.



Solve this by putting the neutralizer after the pump, but they could still clog the drain piping.



So maybe you want to replace the chips a little early, or put a screen in the neutralizer just before the outlet. Marble chips cannot be very expensive. The labour of changing them is probably the big expense.

Henry

Neutraliser

If you want a midnight no heat call, use any of the factory supplied neutralisers. They often block up. We make our one with a Rubbermaid PVC bin and marble chips. The marble chips will last many years. We have not changed any in 10 years and had not one call back for a blocked condensate line. The condensate has the same acidity as lemon juice. Cast iron pipe and all ABS/PVC pipe can take the condensate but depending on local regulations, you might need a neutraliser.

ChrisJ

Worth it?

I'm going to ask a question and please keep in mind I'm essentially an uneducated homeowner when it comes to this.



But, with this problem and the extra cost of the boiler is it really worth all of the trouble in the end?  Standard cast iron boilers seem to last an awful long time on hot water systems and they seem to complain very little.  Do the high efficiency boilers make sense in the end?

M Lane

Chris J-

If you have an old school heating system such as baseboard or radiators,

and you don't mind having a really warm boiler room,

and you have adequate combustion air piped into your boiler room,

then a high-mass boiler (cast iron) will work fine.

Unless your city requires 90% or better per energy codes.

Keep in mind that a lot of energy is venting outside, and you usually are limited to one set point temperature no matter what the temp outside is.

And vent dampers are a giant pain in the arse for us too.

ChrisJ

Ah

This is why I asked.  I didn't even think of outdoor resets.

By vent dampers, do you mean the damper in the flu that shuts when the boiler is off and opens before it lights? 

M Lane

Yes.

They have 2 weaknesses- one is the motor burning out, the other is the contact switch that makes (or doesn't) when the damper opens.

ChrisJ

Ah

Understood.

AlexS

neutralizer

My homemade marble chip neutralizer doesnt have a pump after it, so Im free and clear.  It drains right into the septic system.  The chips have turned a rust color though, that's why I was concerned... A high percentage of iron in these chips?  

Bob Gagnon plumbing and heating

I Pipe In

A drum trap, with the drain plug on the top, instead of the bottom, so you can monitor and add lime chips as needed. I run the condensate up. and over into the drum trap.



Thanks, Bob Gagnon