I have a horizontal closed loop with two waterfurnace units attached (5 ton 7 series + a 2 ton) that's about 4 years old. Has been working fairly well, apart from when it leaked near the circulation pump (outside of the unit) last year. Then last week it started flashing condensate errors. Removed front cover from unit, condensate tray was full, I disconnected the tubing down from it and flushed it out with a hose - fair amount of gunk in there, not surprised it was clogging. Pretty much straight after that, the main thermostat started printing "VS pump" and "High pressure" errors - so I called in the tech and they said it needs a new VS pump. However, the bill from that visit has left me deeply distrustful of the company (they installed the system) - I believe the tech is great, but the bill seems like price gouging. So before they come back to replace the pump (which is under warranty, but apparently the labor is not), I am going to insist they tell me what the labor will be this time. I'm not 100% sure which pump it is though .... There's a unit on the wall behind the main unit that has "Grundfoss magna 320-140 180 PWM" on the pump that's connected to the main line - is that the "VS pump"? If so, it looks like it should be easy to change ... assuming there's some way to shut off the loop without draining a bunch of stuff out. Any idea how much the labor replacing the VS pump should cost? 1 hr labor + callout fee? Previous bill was $129 service call, $96 "clear drain CO2", $79 repressurize loop, $195 loop conditioner. To me, $96 to flush a drain is obscene - I told him I'd done it already, and I suspect it took the tech 5-10 minutes to do. Repressurizing the loop maybe 20-30 mins (I know how it's done), and I looked up the loop conditioner, seems like a reasonable thing to do, but as far as I can see it's about $30 of materials and a bit of time. I think he was here total for about 1.5 hours, and I have a bill for $500 that I think is nearly all labor. Am I misunderstanding something fundamental here, or is this obscene?