wood heating option for a hot tubby Admin
Apr 2014

Message:  I was in the US in January and wanted to visit a showroom.  Please do me the courtesy of responding to this query. I am interested in your cedar hot tubs.  It would be nice to be actually able to see one before purchase.  I live about 1.5 hours north of Sydney for most of the year and then spend the rest in LA.  If you  have showrooms at either location that would be great. The query I have is the US has softwoods and hence your burners are set up for those timbers.  In Australia however ours are hardwoods.  I live in a country location and have plenty of local wood so this is a good option for me.  My experience with burners which can only burn softwoods, placing hardwoods into them can cause them to overheat and essentially melt.  Can you advise please if you have burners for this region.  If not, how can I overcome this problem (whilst staying with a wood burner).   thanks   Steve

Dated on : 04-27-2013

Replies :


Steve, the wood heater's fuel type (hardwood or softwood) is not the main factor.  Dry softwood can produce power exceeding that of hardwood, just not for as long (because the total hydrocarbon content per unit volume is less).  What is important is the ability for the thermo-siphon "pump" flow rate generated  to keep up with the heat (power) generated.  This is especially important with the large heater.  If the heat generated exceeds what can be transported away from the wood fired hot tub heater, by thermo-siphoning (and there is a limit), then a small pump needs to be introduced.  This pump either needs grid power or off-grid power (Solar PV for example).  Otherwise the water in the heater will eventually reach the boiling point, which is no good. Dieter Jung Northern Lights Cedar Tubs Winnipeg, Canada 204 977 1674 Ext 222

Post By : Dieter Jung Dated On : 04-04-2013

Thanks Dieter, so from that are you saying that the setup you can supply will be satisfactory for our conditions?  We can either run the pump via 240 volts or through a step down converter which we have.  In understanding what you have replied providing the heated water can be siphoned away I am not sure what happens when the water temp inside the tub reaches the desired temperature.  At that stage I understand from the literature you need to turn it off otherwise the bathers would end up boiled.  What happens to the heater when that occurs as it itself is still heating. Perhaps I am not that clear on the setup required. Steve 

Post By : Steve James Dated On : 04-04-2013


Steve, there is no automation to heating with the wood heater.  When water is hot enough, the fire needs to be stopped.  We also have no problems supplying an appropriate pump for 230v/50Hz.  Pump would only be necessary with the largest heater. Some level of automation could be added by adding an auxiliary electric heater.  Then once you have brought the hot tub water to temperature using the wood heater, then you plug in the electric heater and it maintains the temperature. A pump is frequently used for the purpose of filtering the water, so it stays clear and to agitate the water so it's temperature stays uniform throughout.  Otherwise you need to stir the water with a paddle, to stop temperature layering (top is hot but bottom is cold). Dieter

Post By : Dieter Jung Dated On : 04-04-2013

  Comments: 0
No Comments!!!
Register or Login to post comment!
Help Desk Software