Where does my boiler condensate water go? PS: Answer now given thanks.

Belenus

Potterton Powermax HE 150 Boiler in a standard brick built detached house in West Sussex both dating from about 2005.

In the picture below you can see the boiler pipework. The second pipe from the right is the pressure release discharge pipe with a black tundish. Pouring a little water into that tundish results in the water discharging, as expected, from an outside drain as in the second picture. I presume the discharged water has been coloured green by the copper pipe. The pressure release valve has never operated to my knowledge and that copper pipe has probably not seen much if any water for 16 years until I poured some in a few minutes ago.

Second left is a grey pipe leading into a white pipe. That is the condensate drain.

Where does that condensate water go? It doesn't go into the same pressure release discharge pipe as the gravel under the outside pipe has never been visibly wet other than from rain. I am also aware that copper should not be used for condensate water as it is acidic and will eat through copper.

There is no other obvious outlet for the condensate water.

Suggestions please.

Thanks.

grumbler

It goes to some waste pipe inside the house

Belenus

Thanks Grumnbler. That makes sense as there is an ensuite behind and beside the boiler cupboard with a shower, bath and WC.

Is it standard practice to do that?

I was expecting a separate drain into a limestone or other neutralising discharge set up. Is that not required?

Presumably condensate water is safe in plastic drainage pipes.

Are Southern Water happy that acidic water is being discharged into sewers? I suppose it is a small amount in comparison to the normal drainage water.

GDB2222

It’s absolutely standard to discharge it into the drain.

It’s not all that acidic.

neilmcl

Belenus said:

Thanks Grumnbler. That makes sense as there is an ensuite behind and beside the boiler cupboard with a shower, bath and WC.

Is it standard practice to do that?

I was expecting a separate drain into a limestone or other neutralising discharge set up. Is that not required?

Presumably condensate water is safe in plastic drainage pipes.

Are Southern Water happy that acidic water is being discharged into sewers? I suppose it is a small amount in comparison to the normal drainage water.

As mentioned, it's completely normal to discharge into a standard PVC waste and onto the normal waste drainage system. Drainage to a specific soakaway is the exception rather than the rule and only done when the former isn't possible.

daivid

Condensate into a normal waste pipe internally is much better than a condensate pipe going outside if you get cold weather. Every big cold snap results in stories of boilers stopping working as the condensate pipes freeze. In the very unlikely event the shared pipe the condensate goes into freezes solid you can pour hot water down from the sink/shower/bath to thaw it out.

Belenus

Thanks everyone for your informative and helpful comments.  

theoretica

My condensate has a pH of about 5 which is only a tiny bit more acidic than rain at about 5.6.  They mostly get their acidity for the same reason - dissolving carbon dioxide out of the air.   Acid rain was around 4.5.