Carrier rtu 50HJQ016 521JH help

[ksefan]

I need a heating charging chart and specs for proper defrost sensor location. Any help would be greatly appreciated, thanks.

[rundawg]

I need a heating charging chart and specs for proper defrost sensor location. Any help would be greatly appreciated, thanks.

I tried to emailed you a couple manuals on this unit, but it rejected the address you have listed in your profile. Update it and I will try again.

There is no Heating Charging chart for this unit. Page 20 of the install manual states to charge in cooling if outdoor ambient is above 40ºf, and weigh in the charge below that.

I will also send you the export version of this install manual (50hz model), as it is the only one that shows the location of the defrost thermostats - see page 24 of export install manual when you get it.

[buford]

Are you getting nuisance lockouts when the od temps drop?

[ksefan]

Yes to the trips. The snow covered roof makes it hard to find exactly when or why it trips.

[buford]

I have got 2 of the 012 size that had the same problems. replaced both of the rev valves on both that would either refuse to shift or move really slow. this helped, but still on the coldest mornings I would get a call of units blowing cold air. Had them cycle power to get them going. I have verified the location and insulated both of the defrost stats, and have tattle tales on the high, low pressure switch's and freeze stats. I also closed down the outside air to zero thinking it was tripping the freeze stat when in defrost.
One of the two I caught running in cool when the call was for heat found and replaced both 1/4 spade terminals to rev valve that were corroded. Had a call earlier this week and could not get there, they reset power and unit has been fine since. I hope to have more info when I get back to see if any of the tattle tails tripped.