Building Code regarding heat pump condensate

[Mike Balma]

In the decarbonization forum, there is a discussion that some building codes treat the water condensate from heat pumps to be the same as the acidic condensate from fossil fuel water and space heaters.  Palo Alto's code, below,  is used as an example of the problem.

I suggest including a line in the building code recommendation to allow heat pump condensate to be used for non potable uses such as irrigation.  Here is the discussion, below.

Regards,

Mike

From: Tam, Christine 
Sent: Tuesday, May 22, 2018 9:09 AM
To: 'Luke Morton'; Rider, Ken@Energy
Cc: Larry Weingarten; Tom Kabat; su...@sudsjain.com; ca-building-d...@googlegroups.com
Subject: RE: [CA-BD] What are the ideal characteristics of an heat-pump retrofit water heater

 

Thanks Luke for pointing out the fact that the condensate from a heat pump system shares the same terminology as the condensate produced by a condensing boiler or furnace. The latter condensate is acidic and requires special treatment.  I had to point out this difference when working with Palo Alto’s building department to put together a permit inspection checklist for the HPWH. Ideally, the condensate from a heat pump system, which is just moisture condensed from the ambient air, should have a different label than the acidic condensate.

 

- Christine

 

From: ca-building-d...@googlegroups.com [mailto:ca-building-d...@googlegroups.com] On Behalf Of Luke Morton
Sent: Monday, May 21, 2018 11:09 PM
To: Rider, Ken@Energy
Cc: Larry Weingarten; Tom Kabat; su...@sudsjain.com; ca-building-d...@googlegroups.com
Subject: Re: [CA-BD] What are the ideal characteristics of an heat-pump retrofit water heater

 

Definitely a worthwhile discussion and perhaps an opportunity to educate some of codes and code enforcers on the specific nature of this condensate.  I like Sean's term of 'atmospheric water', which might be a good differentiator from the caustic sputum from hydrocarbon combustion that seems to be what many think of with 'condensate' 

 

What I have seen as standard on my projects is one of the following:

• Codes that require this 'condensate' to be directed directly to a sewer, or specifically away from anywhere useful.
• Occasionally, I'll see a condensate neutralizer integrated into the system, just for extra protection from.... something.   

• I literally saw this the other day in San Mateo county on a brand new Stiebel Eltron.  

In other words-- you see some ludicrous stuff out there.

 

For the Palo Altans out there-- here is a code section which has specifically prohibited functional reuse of condensate from heat pump space heating systems:

It's item 5, and it reads:   (5)   Condensate lines shall not be connected or allowed to drain to the storm drain system;