" Zach,
We are pleased with how things are working".

" Hi Zach, 
     We just wanted to say thank you for all of your work.  This Air Conditioner cools the house down so quickly that is dosen't run much. 
      Thanks again and I will put  your name out there when people ask about our purchase".
                                                                                                                      --- Jon and Sue

"Hi Zach,
      I turned up the water temp and it seems to heating up now.  Thanks for the quick reply this morning".
                                                                                                                    ---- Jeff N