Mixing radiators and radiant floors

Darin_4

Hello,

I have a 1940's house. It currently has a oil boiler with one pipe mono-flow tees. We love the radiator heat, not so much the radiators themselves. We are planning an addition, bedroom and bath, as well as a kitchen remodel. Kitchen is under heated and previous owners have removed some of the radiators. We would like to radiant flooring in the addition/rennovation. Can you mix the two?

I understand you can use a tempering valve to get the correct temps, but what is the impact on the boiler and the heat calls? Will the boiler short cycle because of a heat call for the flooring when its sized for radiators?

Our oil boiler is 15 plus years old and I was considering replacing it with natural gas. I'm in VA and there are not a ton of oil customers and not much competition on oil price.

Are there better "dual temp"? boilers out there? Is it common to mix radiators and radiant on a single temp boiler?

I've read the How Come? books and looking to the experts for advice. Also looking for a qualified installer in the Northern VA, (Washington DC) area.

Thanks!

Rexford_2

primary loop

If you plan on using the old boiler be sure to install a primary loop. Then you can run your existing radiators on one zone and mix a 2nd zone for you floor. The reason for a primary loop is to protect the boiler from thermal shock. A mixed zone will send cool water back to the hot boiler.
Some of the newer generation of boilers can handle return temps as low as 104' like the Buderus G115 oil fired. Most of the new modulating and condensing gas fired boilers already com equiped for primary piping and can accept return water temperatures much lower.
If your on a budget just add the primary piping to your old boiler. This set up will help make it easier to install a different boiler in the future. Keep looking for a good heating speacialist in your area they should be able match up the proper components for proper operation.

Stewy_2

here a little info on what is takes to add a hot water zone

http://www.heatinghelp.com/heating_howcome6.cfm

if the link doesn't work use the tabs above the questions on the main Wall page and go to "systems"/"hot water"/"condensate loop"

Darin_4

Stewey,

Does the link you provided apply to monoflow hot water as well as steam?

Darin_4

I was thinking of a new natural gas fired boiler, given the age of the oil burner. Would that remove the need for the primary loop? I'm a little confused about what the primary loop would look like. Would it just feed the hot water zone manifold and the existing monoflow loop?

Thanks again for the help.