Heating, Air Conditioning, Fridge, HVAC/Contacter switch connections


Hi John, I am based in Spain. I have a Carrier duct system with a burnt out contacter switch(mouse), so bad that I am unable to read the connector ports printed i.e. NC NO L1 etc. I have a new switch which ha the correct rating and is a dual pole as the original. I do not have any wiring diagrams of the exterior unit. I know that the 230V feed enters at L2 and Fan&Comp are thus at T2, but I am left with 4 wires over, a blue Neutral, which I believe enters at A2 and one of the remaining 3 black wires will enter at A1 to energize switch, however I am then left with 2 more cables that come from the terminal block row, can you help, my concern is where the 3 black cables from Terminal blocks should connect to on the contacter switch (schneider LC1D18), Duct system is an old R22 Carrier 38CHE, Heat & Cool system. Thanks for your help.

   A1 and A2 are on the side and are attached to the 24 volt coil.  The blue ( common ) wire attaches to one of them. makes do difference and the other is usually yellow on Carrier, but, never-the-less, It will be the same size as the blue.  It should be labeled on the box or the side of contactor which 2 terminals are for the 24 volt coil, that is the low voltage control wires that turn the coil into a magnet and oull the cotactor "points" together and let the high voltage go on through to the equipment to make it run.
 If you supply me with model and serial of the Heat Pump I can get a schematic to you to keep on hand.  There are differemces from my country to other countries with voltage, amperes, cycles and the parts themselves.  So, there are a couple ways I can help you.  
 If you have a smart phone, you can send a pic of the name plate and or a picture of the electrical box the contactor sits in and I can text,call or email back from that info, exactly where everything goes.
 Or you can send me pics on here or a detailed description of where the wires in question are attached at the other end and I can tell you where they land know.
 I would prefer the telephone to get it done quick for you.  I work today, on Saturdays, during the winter to try and get to everyone, it is pretty busy from fall to spring.
 john.borgman@yahoo.com is my personal mail box.  You can either send your phone number and time to call orreturn e-mail address and I will send you my phone number to call.
 I have gone so far as to travel to the Bahama's to help one guy that contacted me on here a few years ago, my wife thought that was pretty cool, as I took her and we made a vacation out of it.
 Let me know.....which way I can help.   I am in Portland, Oregon U.S.A as far as figuring the time difference

Heating, Air Conditioning, Fridge, HVAC

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john t. borgman


I am in Portland Oregon at Ben's heating 503-233-1779. I work days, so I can only answer early in the day or later in the evening. I only answer public questions for residential equipment. I am very well versed in gas, electric and heat pumps and will only answer residential applications. I have been known the past decade or so, by my employers as the guy you send when no one can figure it out. Trouble shooting is my special. I understand the physics behind air flow, refrigerants and electricity. I understand programmable t-stats, zone controls, economizers, fossil fuel kits and the engineering thought process in the wiring and construction of residential equipment


I was lucky enough to start in this field almost 30 years ago as an installer, for a company that installed the best duct systems I have ever seen, even to this day. The best ,as far as understanding the way air really flows through a duct system, from the return air to the very last supply register . They also had great pride and the duct work was put in, not only to last 50 years, but to look exceptional. Then as I started doing service work, I was again fortunate that I found a 3 year engineering class being put on be a man that was the educational director for the Entire united states for a society called " the Refrigeration Service Engineering Society " And for the next 3 years I schooled at night and practiced what I learned during the day, a great advantage over schooling and then trying to remember it years later.. Versed in duct design manual J heat gain/loss calculations.

Refrigeration Service Engineer's Society

I have 2 inventions that have gone through the process and been recorded at the National Institute of Standards and Technology from start to finish and thus been invited to national innovation workshops by the dept. of Commerce and the dept. of Energy. They are waste heat recovery devices that N.I.S.T approved as valid and am currently looking for marketing partners to get this product into the hands of consumers and make a BIG difference in Energy savings for every Household and Eatery and take a big bite in the the peak hours power consumption that face our Utilities companies.

factory training in Lennox ,Rheem, Ruud ,Trane, Tempstar ,Carrier, Day&Night, Payne, Bryant, Coleman, Intertherm, York, Goodman, Ultra boilers, Unico, Mitsubishi,Sanyo, Taylor, Nicewonger, Navien. Associates degree in Refrigeration Engineering. Certified with Energy Department, Check-me Program, P.T.C.S (performance tested comfort systems ), have N.A.T.E. certifications in gas, a/c & heat pump.

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