QuietCube harvest problem

[Richvacr]

I have a Manitowoc QY1475 going off on safety limit 2. Freeze cycle pressures are good and time is ok. But in harvest one of the evap. does not drop, it appears to be either left or right side. The harvest pressured are off 50-60psi low and 120- 140 high at 50 degrees ambient. Was there again this mourning at mid 30 degrees and checked the temp incoming and out from head master noticiible to the touch difference - head master letting cooled liguid by in harvest. Manitowoc tech support called back and said head master problem also fan cycle switch - opening at 175psi and closing at 225psi where it should be 200/250.

So here is my question called our Manitowoc supplier and they want almost $300 for the HMV. I think that is more of a resale price. But if it is consistent with Manitowoc prices is there another valve that is cheaper I could use.

Since the HMV is not only for low ambient temp but is the 'hot gas bypass' would a cheaper valve work the same or should I go OEM. Or is my supplier selling me at list prices?

[FEISTY]

First things first. This air cooled unit does not use the headmaster valve you describe but does use a hot gas bypass valve to allow defrost to occur. If valve is leaking or partially restricted you will not provide enough heat to clear grid of ice. I would also double check your pressure readings concerning the cycle points of the fan control. Check on the serial number to verify if warranty may apply that would save cost of hot gas bypass valve. Not knowing where you are located in US , all I can do is suggest you call Alpha Distributors in Harwood Hts, Illinois. Phone # is 708-867-5200. Parts Mgr is Brian. They are on northwest border of Chicago. He is factory sales and service-parts for Manitowok and is very fair pricewise. I would also inquire about a set of factory handbooks covering all models. They include a spec sheet to fill out before calling tech support that will provide all the info they require to diagnose what we can't. Last but not least, many years of working on these units has taught me to stick with what parts they design, especially if a warranty issue comes up. Substitute a part and there goes your warranty. If it is the hot gas valve, have patience as spare space to work is not usually provided. Good luck !!

[FEISTY]

Sorry but long working weekend and my mind slips a bit. You didn't give a lot of info on unit. Do you have a remote condenser outside that is exposed to winter temps? In the outdoor cond. case a headmaster valve would be installed but then your fan would not cycle on pressure. It would run whenever compressor is on. Headmaster would switch internally, most likely at 180psi since you are running R404 *****. What you said tech support told you leads me to believe it is remote condenser indoors with fan cycle control. Better if you double check and, if need be, write back with more info. Again...sorry for afterthought. No sleep takes its toll.