Ooo-rah Gunny: This unit is not a rusted hulk, it's always been high and dry, gets just enough sun to dry it off every day and I've kept it clean, repainted and rustproofed it when it needed it over the years (was trained well in that department), had every panel off and replaced all the seals and insulation. The components are modular and mechanical, so it actually seems that it would be easier to repair than the electronic circuit boards, just remove the bad part and replace. I've watched the few times it was serviced, first couple of times by the tech equivalent of a Gunny (had seen it all), last time by a younger tech who called the senior tech for advice. They just removed the bad contacts or switch or circuit breaker and popped in the new part. Only thing is that any tech under about 45 isn't familiar with the type.
It would help the next tech that comes to look at it if anyone had the service diagrams for that type/model or knew where I could download them, they have faded and are about impossible to read. I'm on my own financially, been applying for some government jobs, takes forever to hear if you hear at all.
I just talked to an independant tech, he's on his way to look at it. Says he can probably retrofit a circuit board to replace some of the defrost timer components. I'll know in an hour or so.
Got a call from the tech (he's more of a handy man that works on HVAC partime); he said the defrost timer is not working, he took it apart and oiled the bearings?, said it worked for a few minutes then stopped. Said the bulb was also empty? Also said that he could tell the system was low on coolant because the pipe was not hot enough and that it iced up very quickly with an outside temp of about 50 degrees it shouldn't ice up that quickly in heat mode??
He said he should install the type of schrader valve that pierces the low pressure line and add coolant, said it takes 4-5 lbs?? Does all that sound correct?
He said the timer was a 120Volt paragon B-51-20; does anyone recognize that part?? Said he would try to find a replacement but also said he had never worked with that type and that most everything now is 24Volts.
Anyone know where I can find that part or what could be used to replace it?
Guys; I say again, I have no money. A new package unit would run me around $$$$, don't have it, can't get it, my car isn't worth that much and besides, it's broke also, along with my refrigerator, washing machine, and microwave. I'm in Tennessee and found a part-time tech who said he's never worked on anything this old but is trying. My thermostat is also very old, original tipping mercury bulb type; it only has Heat, Cool and Auto positions, no emergency heat choice.
Does the parts diagram below help anyone suggest a fix or replacement for the defrost components??
Last edited by jpsmith1cm; 01-17-2012 at 06:09 PM.
Reason: Removed pricing
Gunny; As I mentioned a couple of times below, I found a tech, I'm NOT doing this myself, I'm just trying to help out the tech as he said he's never worked on anything like this before and didn't know what he could find to replace the old components. Was hoping I'd find an old hat who knew something about this type unit. The thermostat does not have an Emergency heat setting, just Heat, Cool, and Auto.
I have to say this site has some unusual rules. I'm a member of a few 4x4 truck forums where everybody helps everybody, from Master mechanics to vendors to dealer parts managers to back yard mechanics. A very open and free flow of information no matter the topic; brakes, fuel systems, electrical, suspension, steering, ----, and no one is worried about lawsuits or competition.