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Have you tried jumping TT
I dont see TT
I have TV and T
The terminals where the thermostat connects
If jumping the thermostat terminals doesn't pull the relay in but you can get the boiler to work by manually puling in the contactor then you probably need to replace the L8148
What can I check to see if its bad
I would hate to waste 180 bucks
Doing what I just described is the field test for determining if the control works.
is there not a way to check the transformer or the relay itself?
when you say TT is there a actual terminal named that?
Neither of these components are serviceable. If the control doesn't function properly we replace the entire control. If you modify the control in any way you are assuming liability for any future (potentially serious) failure.
Is there supposed to be a terminal named TT
It depends on which version of the control you have. Some only have TT others have 3 thermostat terminals. If the control has functioned properly until now with the thermostat connected as it is then how they name the stat terminals doesn't matter
When I say TT I mean 2 T terminals
thers is a terminal named TV and T and W and Z
Z and W look like they have a brass jumper between them
If it has worked properly for a period of time then the terminal designation is not relevant. If you want info on what these terminals are for I need the 4 numbers that come after the E in L8148E
when you say jump the terminals, I was just wondering what ones
The terminals the thermostat wires are connected to
there was three wires connected red, blue and whitw
The number you gave me is an OEM number and I can't access the schematic. I am not familiar with a 3 wire stat config and with out a schematic I am in the dark. I'll opt out maybe one of my colleagues is familiar with this
See fig 6 on link below for internal wiring of this control, also check electronic board for any burnt portion of circuit board have seen this in past
no burnt spots on board
it does nothing mechanically, is there a way I can check it?
If you jumper tv and t terminals it should start
Is there voltage on tv and z terminals should be 24vac
can the relay be replaced?