Installation Issues

Old 12-22-14, 07:37 PM
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Installation Issues

Over the summer, I had my central A/C replaced with a A/C and heat pump unit with electric backup. As a secondary backup which would require manual switching, I kept my hot water oil system. The thermostat that previously was A/C and heat became just heat and a new thermostat was installed for the A/C and heat.

I went to turn on my oil heat (something I admitedly should have teted after installation) and nothing. The thermostat sounds like it should be working but isn't. I know the boiler is fine since my hot water is fired off it. I took off the oil control panel and found this:


The metal box I know was there previously. When in installed the original programmable thermostat, there already was a metal box there so I figured it was necessary. The wiring looks like it's 120V and I did attach the ground wire to the box but I have no idea where it actually goes since it is actually a low voltage connection traveling over grossly oversized wiring.

The wire running up and through this box is the new wiring going to the newly installed thermostat. My first question on this is, is this running of the wire through the box permissible?

Below is my suspected cause for the issue. The wire appears to have been damaged when they ran the new wire up. Could something like this be causing the issue?


Just for reference, here is where the new wires end up going for the new thermostat. I didn't want to take it off the wall since I'm making an installation warranty claim, but the wires are all coming through a hole in the wall that is behind the left area of the thermostat plate.

Old 12-23-14, 05:26 AM
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There should be a connector in the box,running the wire through the box is not an issue except for lack of connectors,not sure why the installers just didn't fish the new wire up to the new location.
Is that a block wall?do you know where the 2 black wires terminate at the boiler?
Old 12-23-14, 09:05 AM
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There is something strange there. It looks like a cloth covered romex was originally in the box. The reason the connector is not in is because they fished a new thermostat cable up thru that box to your new thermostat.

The presence of that romex signifies high voltage as in old style 120v thermostat. They may have converted the boiler to run on a 24v control signal which would mean that cable passing thru the box is fine.

When they moved the A/C to the new thermostat they should have removed all extra wires from the old thermostat. That heavy wire.... white and black..... should be connected to the W and R or Rh terminals.

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