Adding solar panels to OWB

[toecheese]

Does anyone know the install procedure? Or a website or video to point me in the right direction? This would be adding it to a existing boiler. Hoping this would cut my wood consumption.

Thanks

 

[Hydronics]

Can't tell where you live but typically solar is best for dhw in summer but with enough panels and storage can supplement heat in fall and spring. There is a solar website, google it. Check americansolartechnics.com a poster here located in Maine.

 

[lectraplayer]

There is a sorts of stuff on eHow about building and installing solar heating panels. However, I have not messed with it yet.

 

[peakbagger]

Adding solar hot water panels to an OWB does not make a lot of sense. They actually will end up working like radiators and increase the wood use. SHW puts relatively low temperate hot water and its most efficient taking cold water and heating it up to warm. Conventional baseboard type heating returns relatively hot water (140 degrees) so the using the panels to preheat the return water doesn't gain you much expect in summer when you don't need. You could use evacuated tubes but they are very expensive and many brands have reliability and longevity issues.

You are far better off dealing with the fundamental problem which is an OWB is inherently inefficient as most people run them. OWBs have to be sized for the worst case heat load and generally are oversized. They can burn efficiently at full load if dry wood is used, but most of the time the boiler is oversized and running with the damper closed. This gets worse as the heating load drops in the shoulder seasons. In theory a large thermal storage tank could be incorporated but then it operation needs to be matched to the tank temp and has to be relit frequently.

 

[maple1]

I would be kind of surprised if a simple solar panel add-on would make as much heat as the OWB looses.

 

[lectraplayer]

I know to be efficient, you would have to know the temperature of your water and the panel, and only run the solar collectors when the panels are warmer than your water.

 

[Bob Rohr]

It's possible a thermal array could cover a large portion of you summer DHW use, if you plan on burning the OWF for DHW year around?

A stand alone solar DHW system would be better if that is the case. Typically 1.5 gallons of storage per square foot of collector. So if your OWF holds 200- 300 gallons or more, it would require a large array to keep it at a useable DHW temperature, or even pre-heat temperature. And the flue pipe in the OWF would just siphon away much of the solar input.

 

[lectraplayer]

...so close the valve for the OWF when not in use...

 

[maple1]

...so close the valve for the OWF when not in use...

That won't accomplish much if the panels are hooked to the OWB. Which was what the OP posted about. I think.

 

[Bob Rohr]

...so close the valve for the OWF when not in use...

I assumed the OP meant installing the collectors at the OWF. Sure, if they were tied into the piping either with a manual or electric zone valve the OWF would be able to be isolated.

 

[lectraplayer]

That won't accomplish much if the panels are hooked to the OWB. Which was what the OP posted about. I think.

It's hard to tell. I think he's just wanting to add solar heat in addition to the boiler he already has. ...so the obvious still needs to be discussed, including where the solar panels go.