I've got an older trane heat pump (mid 80's?)at a rental unit I own. The heat pump portion seems to be working somewhat (supplies some heat till it gets pretty cold, a/c worked fine this summer), but I get nothing from the auxiliary heater when it's too cold for the heat pump. I've cleaned the filters as well as the coils on both the inside and outside units. I need to see if I can get this fixed myself because I've got a couple of schmucks in the unit (months behind in rent, in process of evicting them) and money is very tight. <br /><br />I've got a generic repair book and will test the outside unit tomorrow (compressor, contactor). <br /><br />Couple of questions: what temp should I expect from just the heat pump at various outside temps (say 60 deg and 40 deg). When it was around 40 deg. outside seems like I was getting 70 deg air at the register. Inside unit is in a crawl space; unheated, but still much warmer than the outside. <br /><br />Seems like when it was between 40-45 deg outside I was getting 70 deg air out of a register fairly close to the inside unit.<br /><br />Can I check the freon pressure myself with fairly inexpensive guages I can pick up locally, or do I really need a profesional for that?<br /><br />On the inside unit, I think I've got two heating elements (two limit controls?), a contactor instead of multiple sequencers, a heat relay(?), a 24V converter, and one other 'boxy' electrical component I can't identify (I think it's connected to everything else; contactor, heat relay, thermostat, 24V converter, blower, and outside heat pump). It kinda looks like it might be another type of contactor.<br /><br />Wish I had taken a pic or the inside wiring, unfortunately the rental unit is about 1.5 hours away and I won't be back there till tomorrow.<br /><br />I did note that on the other (working) side of the duplex when I had a helper turn the heat up to the point the aux heat came on the contactor closed. On the 'broken' side, the contactor didn't close under any circunstances.<br /><br />So I'm wondering if:<br />1) I'm short on freon, which is making the heat pump inefficient to start.<br /><br />2) If the inside contactor is faulty, or whether it might be something that is supposed to trigger the inside contactor that's bad (thermostat, some control from the outside unit, etc.).<br /><br />3) Haven't tested the actual heating elements yet, but when I manually pushed in the aux heat contactor a helper siad the air blowing out the register was warmer.<br /><br />I know this is lengthy, but any suggestions as to order & how to test different components?<br /><br />btw, no fuses that I can see on the inside aux. heat unit. It does have it's own circuit breaker at the inside unit (40A I think?) as well as the two ganged (240 V) breakers in the main panel inside the house, one for the outside unit, one for the aux heat unit. I do know that this thing uses multiple power sources I need to deal with for safety, and that I should discharge the capcitors in the outside unit if I mess around with it to any extent, so hopefully won't put myself at too much risk w.r.t. frying.<br /><br />The wiring diagrams pasted to the equipment unfortunately are pretty faded/dirty, so they are of limited use. I'll call Trane to see if they have copies, but I bet they will be very hesitant to give em to me if they've even got easy access to em.<br /><br />Of well, any input appreciated!
