How do you know if your Heat Siphon is an ANALOG MODEL?
Suppose you just bought a house and it has a pool and you see this Heat Siphon which you would like support on but don't know what type or model it is ?
First look at the front - if your Heat Siphon has a KNOB instead of a digital display - it's ANALOG. Look at the nameplate for the model number and if it DOES NOT START WITH A "D" then it's ANALOG.
The current ANALOG models with the TIMERSTAT PRO, like the one pictured above look exactly like the Digital models, except the control pocket door in the upper left has a knob and different decal.
Analog models from 2010 to 2014 have the same gray cabinet and the doors are the same, with a blank door in the upper left covering the digital control pocket, and just below that door a larger door with a knob in the lower right coner.
Older analog models may have an almond color PVC cabinet instead of the new Titanium Gray. They will have the knob in on the lower right corner of the control box door, but they will not have the smaller door on the upper left as they have no digital pocket.
On all ANALOG models the control circuit is wired in series, like a christmas tree's lights from one to the next - ALL control switches must be closed to turn it on like all bulbs must be good to light the tree. If any control is "open" or faulty it will prevent your Heat siphon from starting. Troubleshooting merely involves jumping out each control until the Heat Siphon starts to find the faulty control or the condition preventing operation.