insulating condensate tank

[clwestphal]

Does anyone have any experience with insulating their condensate tank on the boiler? Also insulating the mash tank, I take it there aren't any downsides with doing that.

[Silk City Distillers]

The act of returning condensate to the boiler is actually the energy saving measure - compared to dumping condensate down the drain, and feeding the boiler with cold water - which was actually commonplace at one point in time. So, the fact that you are returning condensate is a positive. The downside is that if you maintain a very high condensate temperature, you can actually cause cavitation in the condensate return pump, causing damage to the pump impeller. The biggest bang for the bulk is going to be insulating the largest surface areas exposed to the biggest temperature differences. Sometimes it's easy, like the steam and condensate pipes, sometimes it's more difficult, like insulating a jacketed tank.

[meerkat]

I agree with James that cavitation can be a real problem with condensate pumps. These pumps always require careful selection and positioning relative to the tank. If you have an existing pump then check the NPSH requirement before you raise the condensate temperature.

The amount of heat required to raise the condensate a few degrees is small compared with the heat required to vaporize the water and generate steam, so the economic advantage may not be much in insulating the condensate lines. In my experience, insulation of condensate systems has mostly been for personnel safety and inaccessible lines are often left uninsulated.

[clwestphal]

Thanks for the info. I'm going to get my building sprayed with insulation so I will have them do the pipes at the same time.