Wood fired pool heating
The energy prices are raising higher than ever before. The most effective way to heat a swimming pool is probably a solar collector or a heat pump. But if you have a huge stock of firewood like me, a fire-based heating installation is an option to consider.
The principle is simple: a heat exchanger in the chimney of a garden stove. The heat of the fire and the gasses are used to heat the water. Also making the heat exchanger itself is not complex or difficult to achieve. A flexible copper tube is turned into a spiral and at the ends equipped with connections for a garden hose.
In the swimming pool finally I placed a pump with a low flow rate I had laying around.
An initial test was done with a small bath. The temperature of the water raised soon to a temperature that was no longer tolerable to the bare hand. The bath had a capacity of about 80 litres.
This is obviously nothing compared to the pool for which the heating will be used, an Intex pool with a capacity of 12 cubic meters.
on Sep 5th, 2008 at 10:28 am
how long is the copper pipe?
on Sep 13th, 2008 at 2:26 pm
I had this idea to do with a paddling pool, just with my mates for fun in winter.
It’s probably going to be about 4000 liters, but i’m not sure how long it would take to heat to a good enough temperature.
My chiminea isnt that big bit packs out alot of heat.
Also would it ever got hot enough for convection to take over from the pump.
Email me if you have any tips.
Mike
on Sep 14th, 2008 at 12:39 pm
Steve:
I used 5m of 15mm diameter tube. That’s not much but I’m afraid the water will become too hot when I make it longer. This could ruin my garden hose I use to transport the water from the exchanger to the pool.
Michael:
If you want the water to get hot (+40°C for a hot tub) fast you should use a smaller pool. A smaller pool also will lose less heat to the environment.
I wouldn’t count on convection. The current will be rather slow. I tried it with my setup but as mentioned above the water becomes too hot for the garden hose. When I turned on the little pump steam was coming out of the, at that time very flexible, garden hose! To have a better flow you’ll have to make sure the exchanger is positioned far enough below the water in your pool.