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Steve D'Gerolamo
01-11-2009, 01:05 PM
Condensate from high efficiency boilers is very acidic. Can it be plumbed directly into the home's sanitary drain or does it have to be treated first?

I was at a new home yesterday with 3 HTP high efficiency boilers being installed (500,000 btu each) and there is continuous condensate dumping from the units right into a sump well. Not sure if this won't affect the life of the sump pump.

http://www.ultimategarage.com/garageprojects/htp109e.jpg

Impressive installation....there are also a pair of 200 gallon indirect water heaters.

http://www.ultimategarage.com/garageprojects/htp109d.jpg

John Arnold
01-11-2009, 02:51 PM
Condensate from high efficiency boilers is very acidic. Can it be plumbed directly into the home's sanitary drain or does it have to be treated first?

Depends on your area, I believe. I recently attended a seminar given by a heating guy from Rhode Island and Massachusetts, and when he mentioned treatment of condensate, all of us PA (and maybe NJ?) guys didn't know what he was talking about.

Chuck Melocco
01-11-2009, 04:32 PM
The condensate from 90% gas burning appliances is typically no stronger then urine and it is allowed to be discharged into the sanitary sewer system. The flue gases from the same appliances also has an acitic content, which is the resone for the PVC flue pipe.

John Arnold
01-11-2009, 04:40 PM
The condensate from 90% gas burning appliances is typically no stronger then urine and it is allowed to be discharged into the sanitary sewer system. The flue gases from the same appliances also has an acitic content, which is the resone for the PVC flue pipe.

The "condensate" and the liquid produced from the "flue gases", as stated above, are one and the same thing, are they not?

As I said, it's my understanding that in Rhode Island and/or Massachusetts, at least, treating ("sweetening") the acidic condensate is required. I don't know about other states or regions.

Markus Keller
01-11-2009, 05:28 PM
This question came up a while ago. I think most stated it was Ok for direct discharge in most areas. Some maybe not. Ok around here.

Jim Robinson
01-11-2009, 06:55 PM
It seems to be okay here, but then again so are a lot of things.

How big was that house? It must be gigantic. That much boiler capacity would heat most of my street.

Jerry Peck
01-11-2009, 07:50 PM
Looks impressively nice ... until you start looking at the details ...

Is it just me, or do those sediment traps look like the caps on at the floor?

How on earth is one to unscrew them to empty the sediment trap?

Ron Bibler
01-11-2009, 07:53 PM
Looks impressively nice ... until you start looking at the details ...

Is it just me, or do those sediment traps look like the caps on at the floor?

How on earth is one to unscrew them to empty the sediment trap?


Jerry is there a set drop for sediment traps? or are they to short?

Best

Ron

Billy Stephens
01-11-2009, 07:56 PM
Looks impressively nice ... until you start looking at the details ...
.
Or the Water heaters sitting directly on the floor.
..

Jerry Peck
01-11-2009, 09:11 PM
Ron,

Typically (i.e., "typically" means it is in the IRC commentary but spelled out in the IRC itself) the minimum drop is 3".

However, my point was that the shut off valve is installed upstream of the sediment trap to allow the gas to be shut off, the sediment trap unscrewed, emptied out, then re-installed ... and that there is - "looks like" - there is no room for that to be unscrewed and thus no way to realistically clean the sediment trap.

Ron Bibler
01-11-2009, 10:36 PM
Thanks Jerry. I ask that because i had a home the other day that had a drip leg but it was short like 1 inch.

Best

Ron

Steve D'Gerolamo
01-12-2009, 06:18 AM
.
Or the Water heaters sitting directly on the floor.
..

Is that a problem? I have a much smaller SuperStor unit at my home and its right on the floor. SD

Steve D'Gerolamo
01-12-2009, 06:23 AM
Looks impressively nice ... until you start looking at the details ...

Is it just me, or do those sediment traps look like the caps on at the floor?

How on earth is one to unscrew them to empty the sediment trap?

Here's another view of the boilers and a few other pics I took in the mechanical room....there is room to unscrew the caps. A friend of mine was over at the house on Sunday doing the control wiring. He did notice a problem with the mounting of one of the recirculation pumps as some of you will see below.

Also, the boiler installation is very tight. These units are meant to be stacked and doing so would have allowed a lot more room around the units. Originally, the job called for 2 boilers but it was increased to 3. This installation makes the job across the street from this home (see Munchkin and Chiller HVAC (http://www.ultimategarage.com/homegarage/munchkin2.html) ) look tiny.

http://www.ultimategarage.com/garageprojects/htp109f.jpg

http://www.ultimategarage.com/garageprojects/htp109g.jpg

http://www.ultimategarage.com/garageprojects/htp109c.jpg

http://www.ultimategarage.com/garageprojects/htp109a.jpg

http://www.ultimategarage.com/garageprojects/htp109b.jpg

Billy Stephens
01-12-2009, 06:33 AM
Is that a problem? I have a much smaller SuperStor unit at my home and its right on the floor. SD
.
Only when it leaks Steve. :D
.

Jerry Peck
01-12-2009, 10:05 AM
He did notice a problem with the mounting of one of the recirculation pumps as some of you will see below.





http://www.ultimategarage.com/garageprojects/htp109a.jpg



The shaft on that lower pump is supposed to be horizontal, if I recall correctly.

I also believe that the PEX is supposed to come off the manifold straight, be strapped and supported, then bend.

I don't like that NM cable hanging and exposed like that to the pumps either, really should be in flexible conduit for protection (this is arguable position, so I am sure I will get arguments on it :D ).

Steve D'Gerolamo
01-12-2009, 10:18 AM
The shaft on that lower pump is supposed to be horizontal, if I recall correctly.



Exactly! In all fairness with the other stuff, the installation is not yet finished. Hopefully the local building inspector would catch anything not to code. SD

John Arnold
01-12-2009, 10:45 AM
... Hopefully the local building inspector would catch anything not to code. SD

As a famous linguist once said, "Abandon hopefully, all ye who enter here!"

Anyway, I wouldn't count on it.

Morgan Audetat
08-22-2011, 10:07 AM
If all you can find is a short nipple on the drip leg, you are looking too hard. Technically, 3.5". These have room to screw off but I have rarely found a drip of anything on natural gas installations.

The circulator drive shaft should lay perpendicular to the pipe and horizontal in low pressure applications and MC is standard for wiring.

Condensate from condensing boilers has a pH between 4 & 5 (a lemon and an orange) and will not harm plastic waste pipe or septic system. If the condensate runs to an old cast iron drain where a softener or AC unit is not also drained erosion may be an issue...in a decade or two.

Electricians rarely do the near wiring.

ted kidd
09-12-2011, 12:29 AM
It seems to be okay here, but then again so are a lot of things.

How big was that house? It must be gigantic. That much boiler capacity would heat most of my street.

So, how many sf? 40,000?

How much solar was installed? What an interesting project.