Tom, I am trying to keep mine in the 120F range. I believe they are spec'd to slow down at 140F (Coorrect me if I am wrong Tim!). On many occassions I have seen mine slow in response to over-heating. After my acrylic got crazed, I bought a non-contact temp. sensor to find out how hot they were getting and regularly saw readings between 135F and 145F. I now run them between 60 - 70% or so to keep the temp. down, although as you know, I don't really know what the percentage is or even if the control is linear.
Your temps. are well below the danger zone and within spec. and as Tim wrote, I wouldn't worry about it. If you feel that temps. are rising, I would visually inspect the gasket to make sure that the magnet is not rubbing on them. The wear is very apparent and can be the cause of excessive heat.
I think there are many different things playing into my Vortech experience, most of which are well beyond normal R & D.
Food for thought in regards to why I am having so many issues:
-- Tank room temp. and humidity is above normal (if this does indeed become the top-line issue, I am afraid there will be a lot of resistance to the MP-40 long term);
-- I am using 1000W Sunlight ballasts which have been indicated in some interference issues;
-- my tank is 3/4" acrylic which may or may not be exact, and is on the outside edge fo the Vortech's specs. It could even be slightly bowed and causing a problem.
-- I was using an ACIII Pro to control the pumps (I can't risk any ON/OFF cycles at this point so I just leave them on 24/7);
These are just the lingering questions in my system. Tim has worked with me throughout this ordeal and I can imagine that the Eco-Tech team is getting tired of dealing with me. Unfortunately for them and me, I cannot go back and put in closed loops without even more pain and the total dismantling of my system, so they are stuck with my outer-edge install. There really are no good alternatives IMO as I distinctly dislike their closest competitor's products with the heat, wires, etc. in the water column. In fact I plan on installing two more MP-40s bringing the total to 7 before the end of the year. Lucky Tim! :lol: I sure wish I could run them flat out too.
I am currently thinking about how to bring down the temp. and humidity in the tank room without instaling a chiller or HVAC unit. When I originally designed the system, I added extra valves for later expansion and one was slated for a heat exchanger/ground loop. That may help control the tank temp. but its affect on the tank room itself may not be enough to counter the current conditions.
One of the key reasons why I selected the Vortech was to make my system as electrically efficient as possible, but unfortunately, I may have to eat up that savings with and HVAC unit and that is really depressing.