When to let water out of boiler drain. Burnham Gas Steam

DO NOT drain any water, especially weekly.

If it was a float type LWCO, you should be dumping that weekly with the burner on, but I assume this new install has a probe type LWCO. Pictures would help us.

You may want to have the system flushed out every few years but other than that, no, no draining.

That instruction of draining water weekly comes from an old style LWCO control that requires that procedure. They actually have the necessary valve as part of the control.

Unless you have one of the float type LWCO controls that instruction is not for you. Most new boilers are equipped with a probe type electronic LWCO control. They only require annual maintenance. Do not open any water drain valves during the heating season to let water out of the boiler unless it is required for servicing some other part of the system. You want to keep from adding fresh water on a regular basis.

That water in your boiler is actually equivalent to distilled water after several weeks of operation because it will all have been boiled off at some point to make steam then returned to the boiler as condensed water. That is the process for distilled water, boiling off the water and condensing it back into water. That way all the contaminants are left behind. That is what you don't want in your boiler or float type LWCO so you flush them out.  But the new water added will contain more contaminants.    

So if you don't have a float type LWCO, don’t add new water  every week.  Wait for the entire year of operation then you can flush out any muck that forms inside the boiler from that entire year of operation all at once.  Make sense?

Hope this answers your query.

if it is a float type lwco it isn't just to test it, it is also to flush muck out of the float chamber so it doesn't end up binding up so a bit more water than what it takes to shut it down isn't a bad idea.

So, I was talking to a Burnham rep that told me they have a water quality issue that the chlorides stay dissolved and get to a higher concentration because of the location of the flue. Apparently they have a tendency to rot the return nipple so draining the steam max is actually a good idea. Could have been BS but it sounded like logic unless the water was treated.

they don't know what they're talking about. sodium chloride gets in water supplies largely as road salt. If anything draining and adding water will allow you to put more chlorides in the boiler with the fresh water you have added while some of the chlorides in the previously added water have precipitated somewhere in the system. unless you are adding deionized water any water you add to the boiler increases the minerals in the boiler. Unless you have a float type low water cutout the only times to drain water for maintenance are to remove and clean the probe for the lwco or if you are going to flush the mud out of the returns and the boiler every couple years or so and with certain water chemistries flushing the mud doesn't need to even happen that often.

I don’t think the boilers actually distill the water because probe type LWC do not work in DI or distilled water

We bought a handful if different brands and tested them with the DI water from the cart

Any sludge, sodium, dirt in the water will raise the conductivity of the water high enough for the probe to detect

Adding any fresh water brings in new minerals and O2. The steam conditioners help scavengers the O2and also help keep minerals in suspension to prevent sludge generation

They're the only ones getting chlorides in their boiler water. If you have another brand that doesn't happen apparently.