Nest Thermostat Wiring for Baseboard Heaters
Since you have a R841C (with an integral transformer)

You have your terminals on the relay confused. Connect RH to the HOT terminal from the relay and W1 to to the NEUTRAL terminal from the relay.  C on the Nest is left unconnected, and you do not need a separate transformer here.

If this was an R841D (standalone relay)

You have your terminals on the Nest confused here.  Connect the hot wire from the transformer to the RH terminal on the Nest, the neutral wire on the transformer to one end of the relay coil (it doesn't care which way it's wired) AND to the C terminal on the Nest, and the other end of the relay coil to the W1 terminal on the Nest.