Its the last job of the day, 4:00 Friday night.  You are called back to a previous mini split installation. You walk up to find that the unit is giving a communication error. This fist of all doesn't make sense since the unit has worked before. So first thing is to get on tech line and wait for someone. Then they take you through testing boards and find that the board is bad. Some units will have multiple boards and the answer we seem to always get is "...replace all the boards". So now the customer is out for the weekend and into late next week. Then you get the new boards, customer is probably a little mad that they were not in stock, and put it all back together again. Then it very well could happen again.

Obviously there could be something wrong with the unit. From what we have seen its really a matter of what is coming in to the unit. All DC inverter product has sensitive electronics like a computer. A computer however has a power supply that make sure the PC is getting the proper voltage to its components. In these  mini split and unitary inverters we don't have that. Typical units have a ranger of 187-253VAC for incoming voltage. Anything under or over could possibly ruin components. We have seen a lot of areas being delivered higher than allowed voltages, so this in turn turns in to a long service call, waiting for parts, then back to the job  a later day. So the solution to this is to work into your pricing a surge protector/line voltage monitor.

We suggest the Rectorseal 96421 or Rectorseal 96424 (with disconnect), or we still have the ICM493 available. It is more expensive than standard surge protectors but it does so much more. You get 5 actual surges and also a line voltage monitor that looks at both over and under voltage. Most units do not look at over voltage. It also uses a contactor to take both legs of unit from power source. Unlike most others that only offer parallel wiring.

So yes it may be expensive but will save you on nuisance calls later. Which will save you big in both time and money.