How do Istop oil burner from heating hot water?

[mwatkinson]

I have a 25 year old oil burner that does not do an adequate job heating our hot water. I have bought an electric hot water heater which I am comfortable plumbing in, but how do I stop the old "sidearm" water heater? Just cut and cap the pipes? Will the oil burner still try to heat the hot water?

[richapplyguy]

You can't prevent the oil burner heating the hot water pipes.
Do you have low flow rate from the boiler hot water takeoff, if so there is a fix for that. Please post.

[mwatkinson]

I'm not sure I understand the question. Could you elaborate? There is a mixing valve for tempering the hot water. Is it ok to just cut and cap the pipes in and out of the boiler? I'm concerned that the system will be calling for hot water and firing the burner for no reason. I only want to heat the house with it.

[richapplyguy]

I am not an expert on hot water boilers. My boiler has a valve that feeds extra water to the radiator pipes if the pressure goes down. I assume this is a pressure regulated valve,but I assume it doesn't work as I have manually added water to the pipes to fill the radiators up all the way.
If your sink hot water pressure is less than your cold water then you have low flow rate. You can fix this with the use of a turkey baster; run a calcium disolving acid thru the boiler to clean out deposits. I found most deposits occur at joints and valves and little inside the boiler. I used "calci-solve" I got at the plumbing supply. Carefull with it it dissolves concrete on contact!

[richapplyguy]

Will try to answer your questions by example. I just added a electric hot water heater to heat the water in the Summer when the boiler is off. I just added valves to the pipes to switch between boiler and hot water heater. No reason to cap off the boiler if you can clear the calcium out. Your reference to a "mixing valve must be the auto add valve I mentioned.