Bad smelling hot water

Solar Domestic Hot Water and Solar hot water heating for homes and pools
Beardo McShorts
Posts: 55
Joined: Thu May 21, 2009 10:25 am

Bad smelling hot water

Postby Beardo McShorts » Tue Jan 19, 2016 4:01 pm

About 2 months after I installed my SDHW system I noticed a problem with the smell of the hot water. This is something that I have never run across so I thought I would post it here for your info.

The hot water started to smell like rotten eggs and it was only the hot water. My plumber friend dropped over and told me that the problem was something called anaerobic bacteria. Apparently my water supply has a high bacteria count and this is causing the problem. I added some chlorine to my well and the problem went away for a few months. I had the water tested and sure enough, it showed a high bacteria count, so this is definitely the cause.

He suggested the problem is that the bacteria is interacting with the magnesium sacrificial anode and that I should remove it and the problem will go away. What are your thoughts?


Opinions expressed are my own. You can't have them. Go get your own damn opinions.

Off Grid With:
Solar: 6x 235W Mono (1410 Watts)
Charge Controller: 60A CAP
Turbine: UP2KA 2000W
Inverter: 1x 3000W Charging Inverter
Batteries: 12x Trojan L16

Conundrum
Site Admin
Posts: 352
Joined: Wed Apr 29, 2009 5:43 pm

Re: Bad smelling hot water

Postby Conundrum » Tue Jan 19, 2016 4:13 pm

He suggested the problem is that the bacteria is interacting with the magnesium sacrificial anode and that I should remove it and the problem will go away. What are your thoughts?


Your plumber friend is partly correct. The sacrificial anode is there to protect the tank from corrosion and is a very important to extend the lifespan of your hot water tank. If you remove it, the tank will corrode much faster than the it would with the anode. With heat exchange hot water tanks, it is doubly important because the free ions will attack the heat exchange coil. The key problem you have is that the bacteria is interacting with the magnesium. The solution is to change the anode from magnesium to zinc and the problem will go away. Zinc anodes are uncommon but are available. Give us a call with the size of the orifice and I'll get you the correct anode to solve this.

Beardo McShorts
Posts: 55
Joined: Thu May 21, 2009 10:25 am

Re: Bad smelling hot water

Postby Beardo McShorts » Tue Jan 19, 2016 4:38 pm

Yeah, I thought there might be something fishy about taking the anode out completely. I really appreciate the info. I'll get back to you with the size in email.
Opinions expressed are my own. You can't have them. Go get your own damn opinions.

Off Grid With:
Solar: 6x 235W Mono (1410 Watts)
Charge Controller: 60A CAP
Turbine: UP2KA 2000W
Inverter: 1x 3000W Charging Inverter
Batteries: 12x Trojan L16

Conundrum
Site Admin
Posts: 352
Joined: Wed Apr 29, 2009 5:43 pm

Re: Bad smelling hot water

Postby Conundrum » Tue Jan 19, 2016 4:48 pm

To eliminate the smell quicker you can put some hydrogen peroxide in the tank when you remove the anode. You can pick it up at the dollar store and you will need about 1 bottle for every 25 gallons of water in your tank. I can't remember which one you had, but if its the regular 300L tank then you should use 3-4 bottles. This will kill off the bacteria in the tank and start you off fresh.

Beardo McShorts
Posts: 55
Joined: Thu May 21, 2009 10:25 am

Re: Bad smelling hot water

Postby Beardo McShorts » Tue Jan 19, 2016 4:49 pm

Yup, its a 300L tank with 2 coils.

Can I use chlorine bleach instead? I read that it will kill the bacteria as well and I don't need as much.
Opinions expressed are my own. You can't have them. Go get your own damn opinions.

Off Grid With:
Solar: 6x 235W Mono (1410 Watts)
Charge Controller: 60A CAP
Turbine: UP2KA 2000W
Inverter: 1x 3000W Charging Inverter
Batteries: 12x Trojan L16

Conundrum
Site Admin
Posts: 352
Joined: Wed Apr 29, 2009 5:43 pm

Re: Bad smelling hot water

Postby Conundrum » Tue Jan 19, 2016 4:52 pm

No, don't use chlorine. That would be a bad idea. With the tank you have, there are 2 copper coils inside it. The coils will react with high chlorine levels especially at a high water temperature and may damage them. Peroxide is a much safer option.


Return to “Solar Hot Water”

Who is online

Users browsing this forum: No registered users and 1 guest