Neutralizing HE burner's condensate

Jadnashua

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I need to check the local codes, but how critical do you think it is to neutralize the condensate from a high-efficency burner, be it a furnace, boiler, or hot water tank? One boiler I looked at said the condensate could be in the ph 3 range. I live in a townhouse - the unit's drains are pvc, but the main line is cast iron (about 20' from the drain).

As opposed to the type discussed for whole house neutralization where there is a lot of flow, here, there would be minimal flow and seasonal (a lot more in the winter! than summer).
 
If it's a real concern you could build a tiny Acid Neutralizer from some PVC parts and a couple of fist fulls of calcite.
The condensate would only be a dribble. Correct?
Then again, orange juice has a pH of about 3. Do you worry about dumping a glass of it down the drain?
 
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I think the consideration here is how much the effluent is diluted. Didn't Terry tell a story here of how a closet bend was eaten through from someone who never flushed? The lower end of urine pH is only 4.5 but most drains are not affected because it is mixed with bowl and tank water. The plumbing code for plant drains in Detroit, 1956 (pre-plastic I assume) states: ...any waste will be deleterious which does not conform to the following specifications. 1. Acidity or alkalinity of plant effluent must be neutralized to a pH of 7.0 as a daily average on a volumetric basis, with a maximum temporary variation of pH 5.0 to 10.0... I expect I wouldn't worry about the condensate if it were being washed down on a regular basis.
 
How much condensate water?

A million BTUs (10 Therms if you are billed that way) of natural gas is about 42 pounds and contains about 10.5 pounds of hydrogen which will produce 11 gallons of water if it all condensed. I don't know what fraction is condensed and what fraction goes out with the carbon dioxide. The acidity in the water is caused by the carbon dioxide that is dissolved in it.

Just to keep things simple, assume that you will get 10 gallons of condensate per million BTUs of gas (1 gallon per Therm). Look at your water bill and your gas bill and see how many gallons of water you use while burning one Therm of gas. That is you dilution ratio. If your water bill is reported in cubic feet, multiply by 7.48 to get gallons.
 
Just a trivia point: Everyplace I have been familiar with bill water in HCF (hundred cubic feet) so you multiply by 748 to get gallons.

Anyway, your water dept. can explain the meters and the billing.
 
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