Radiator help!

[Jamina Metcalf]

I live in California and I want a radiator heating system in my home. It's an old spanish style home built in 1926. There was a furnace in the hallway as the only source of heat. And yes, California is very mild weather, but it can still get pretty cool in the winter mornings. I just want a simple heating system. I've consulted with a few HVAC professionals and was very disappointed with how large the units are and the problem is my home is only 1110 sq ft, so every inch is valuable real estate. I have a flat roof so ducting in the roof is impossible. In my research, I liked how the radiators look number one, but also because it seems I can put the boiler outside and all I would need to do then is plumb the piping to each radiator. Am I missing something? Also, does a radiator recycle water? Because living in California, we are always in a drought, so that may be an issue if it is using too much water.

Any and all advice much appreciated and very welcomed. Thanks!

 

[Reach4]

The water is not consumed in the boiler. There is a thermal expansion tank that lets the water expand when heated without having to vent out. Water usage is negligible. An advantage to that is that you don't have oxygen coming in with new water, so the corrosion is kept down.

I don't know about boilers outside, but they can put antifreeze in the water.

 

[Sponsor]

 

[BadgerBoilerMN]

If you have a tank-type gas water heater you may use it to drive wall-hung panel radiators in each room. Some modification is required. Potable water from the water heater is used to indirectly heat the panel radiators.

Hydronic heating systems circulate water in a sealed system much like your car's cooling system where the engine creates heat and the radiator gets rid of it.

http://www.badgerradiantdesigns.com/hotwater.html

 

[Dana]

It's highly likely that your heat load (the amount of heat you need to stay above 68F indoors at the 99th percentile outdoor temperature, aka the "99% outside design temperature") is WELL within the output of any gas fired tank hot water heater, but is certainly within the output of a condensing tank type hot water heater. Listen to the Badger- that is the most likely solution.

The amount of radiator you need in each room is also likely to be quite small, and much of the expense of retrofitting a this type of heating system will be in the radiation. To achieve reasonable room-to-room temperature balance you will need to do a room-by-room heat loss calculation in order to size the radiators proportionally. If money is no object you could oversize the radiators and install thermostatic valves on each radiator, effectively micro-zoning the place, but that's not going to be money well spent.

If you can use computer spreadsheet tools (Microsoft Excel, etc) it's pretty straighforward to do an I=B=R methods load calculation, from which you can size the radiation, which will be more than adequate. An energy nerd or a true pro would use the somewhat more sophisticated ACCA Manual-J methods, but you can also use online tools based on Manual-J if you like. In cooler climates it's possible to get accurate whole house load numbers derived from fuel use, but in very temperate coastal CA the error from solar gain and hot water use is large using those methods. In this case a I=B=R spreadsheet is probably the best, since you can save and correct it as you figure out the particulars of your construction details. If you need help figuring out U-factors of your construction type, ask.

If you're not on the gas grid there are reversible air source heat pump solutions that will be dramatically cheaper to operate than either propane or electric boilers at typical CA utility pricing. It's more expensive to install than hot water heater based heating, but has the additional benefit of being able to provide cooling (from both the radiators &/or chilled water coils) There are some very thin profile hydronic air coils out there that can do both heating & cooling with a reversible chiller.