ReplyThat unit should only have one temperature control and a defrost clock
see link for manual, you can call them at 800-325-6152 and ask them to fax you a wiring diagram
http://www.truemfg.com/CC_catalogs/t...rz_english.pdf
Professional Member
Naturally the wiring diagram that comes with the unit is long gone. Japanese restaurant so trying to see if the manager has it is fruitless. I'd prefer to have it before I start looking at that rats nest. I notice they use two temp switches instead of a standard defrost termination/fan switch. I tried the web site but it seems they don;t want just anyone looking at their technical data...
Professional Member
That unit should only have one temperature control and a defrost clock
see link for manual, you can call them at 800-325-6152 and ask them to fax you a wiring diagram
http://www.truemfg.com/CC_catalogs/t...rz_english.pdf
If your not part of the solution, You must be part of the problem
Professional Member
it has one of those cheesy defrost timers like they use on cheap units. all plastic with 4 terminals the harness plugs into. There is one temp control on top of the evap and one on the suction line where it comes out of the evap. Each one has two wires. I'm guessing one is for defrost termination and the other for the evap fan. The evap fan is not running no matter how long the comp runs. I applied power and the fan is fine. No power going through the temp switch on the suction line which appears to be the evap fan control. A wiring diagram is always nice,
I can take my meter and trace out all the circuits but it just takes longer. It would be nice if they glued diagram on the inside of the evaporator shroud. That's just me I guess.
Professional Member*
usually the evaporator fan will not come on until the freezer temp drops (40-30f) so as not to circulate warm air throughout the box so you can check the t-stat circuit if the temp has dropped.Originally Posted by gsxrsquid
it has one of those cheesy defrost timers like they use on cheap units. all plastic with 4 terminals the harness plugs into. There is one temp control on top of the evap and one on the suction line where it comes out of the evap. Each one has two wires. I'm guessing one is for defrost termination and the other for the evap fan. The evap fan is not running no matter how long the comp runs. I applied power and the fan is fine. No power going through the temp switch on the suction line which appears to be the evap fan control. A wiring diagram is always nice,
I can take my meter and trace out all the circuits but it just takes longer. It would be nice if they glued diagram on the inside of the evaporator shroud. That's just me I guess.
Professional Member
yep. that is what the switch is for. Usually I see a single switch with 3 leads. It does that same thing though. The evap frosts up, charge is good and it works fine if I jump the switch.
SDC/Educational/Membership Committee*
On these units there are three temperature controls:
1. Box temperature - (adjustable) senses discharge air temp and controls the compressor
2. Fan Delay - (Klixon) mounted on top of the coil
3. Defrost Limit - (Klixon) mounted on the evap outlet
That cheap defrost control has four terminals:
#1 > Hot
#3 > Neutral
#2 > Defrost Heaters
#4 > Compressor/Evap Fan
The drain tube and mullion heaters are energized constantly. That's about it.
I had one similar last week...a TUC-27F...that had be going for a while. I had then fax me a wiring schematic which helped, but it's a ladder diagram and doesn't show the actual wire connections and routing, so tracing through the rat's nest of wires is a PITA.
It turned out there was a broken neutral where the wiring came through the cabinet from the compressor compartment.
Professional Member
hmmmmmmmm I'll call and get the diagram. It's interesting because the fan switch on this unit was on the evap return and not on top of the evap. I wonder if someone else worked on it and switched them? hmmmmm
thanks Ice
Posting Permissions
