Dirty fluid in aqua-hot

[Mauro]

I had to change both circulation pumps this morning with my son's help. Everything went fine and now I have both circulation pumps and the previously changed stir pump in the new model. The original model (2014) was junk. In order to change the pumps I had to drain all the fluid and i was surprised to see how cloudy, and even brown, at the beginning of the flow, it was. Not knowing how it should be after three years of use, albeit for six, seven trips a year, I did not put the fluid back, which means, I did not test the unit after changing the pumps. What I would like to know from those among you that have been using the aqua-hot for some time, is whether a dirty looking fluid can be put back, or if I have to buy 6 gallons of new fluid.
Thank you very much,
Mauro

[Gordon Dewald]

I put ours back after changing zone 1 and 2. Now I have to change the engine heater pump. POS IMO My understanding is if the electric is used a lot the fluid turns brown. They say it is normal.

If you change fluid I think they recommend the system be flushed. I am considering doing that shortly and am getting my head around how to change everything and get the right concentration.

I am going to use distilled water to flush and am thinking how to devise a system to clean each of the zones and the boiler.

[Mr_D]

The fluid will change color due to the heat. Doesn't seem to affect the chemicals in it.