Crankcase Heater for 50 ton Trane Unit

[johnstonesupplyguy]

My customer has a 50 ton Trane Compressor
M/N: CRHR500C-4HAT, 460v r22 50ton.
He would like to replace the crankcase heater on this unit.
That would be a part #HTR-1566.
This unit appears to have no immersion well. The heater screws right into the crankcase.
He is concerned about contaminating his system.
Can he just quickly unscrew the old & screw in the new below the oil level & maintain the integrity of the system? (De-energized,of course.)
Does He have to evacuate the whole system to do this?
Are any Exterior Heaters available for a compressor this size?

[wolfdog]

In theory, if the system is pumped down and the crankcase is at zero pressure, one could unscrew the old heater and screw in the new heater with minimal oil loss.

If there is any pressure in the crankcase it could get interesting.

If he is asking you...to ask us.....I would like to be a fly on the wall watching the whole procedure.

[Carrene #2]

I sure hope you are asking out of your own curiousity, 'cause if you're not, you'd have to wonder if the oil heater is actually defective in the first place, with a question like that.

[maustin]

I'll hang around with wolfdog, this should be good.

[ultratec]

Like was stated above, If the case is at 0psi then you could do it fast w/ little loss ( if you pull a vacuum on the compressor before you pull the heater, it will suck air in and no oil will come out) are you sure there is no well? If not, I would drop and change the oil and install a well type heater.. Evacuate the isolated compressor when your done, even if you dont change the oil. MY 2 cents..

[freonrick]

if the heater is burnt out, evacuate the compressor and open the hand hole and clean out the sump. alot of the black junk will probally fall off the heater. install new heater and oil.

[snipe70e]

Originally posted by freonrick
if the heater is burnt out, evacuate the compressor and open the hand hole and clean out the sump. alot of the black junk will probally fall off the heater. install new heater and oil.

Rick is right. If there is any carbon on the heater when it is removed some will be deposited in crankcase and should be cleaned out.