testing an electrical connection

Hey there, I'm having problems w/ my heating (as discussed in a previous thread), and I want to double check the connections between the thermostat and the boiler isn't the problem. I'm almost sure the connection is fine (the boiler clicks whenever I set the thermostat above the current temperature, or below the current temperature), but I want to have direct measurements that show me that the connection is solid. What is the best approach to doing this?
I just purchased a multimeter, with the following idea in mind -- hit the breaker on the power to the thermostat, disconnect the R & W cables from the thermostat, place the multimeter to 50V DV (the thermostat is 24V, 50 the closest higher reading in the multimeter), flip the breaker back on, and then place the black test lead on the W cable, and the red test lead on the R cable. If my understanding is correct, this should complete the circuit and my multemeter should read the voltage level.
Does this make sense, or am I misunderstanding how this works? I'm working off of reading about cabling and doing electrical work, but all the voltage meter docs I've seen are for wall sockets and such. I thought I'd ping the experts before causing any havok.
Thanks
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Leave the thermostat in place and the wires connected normally.
When the power is on but the thermostat circuit is open (that is, NOT calling for heat) you should see 24VAC across the thermostat terminals. When the thermostat is closed (calling for heat) you should see zero volts.
coldguy wrote:

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Just measure the low voltage at the termnal strip of the Boiler : R and C....then again at the terminal strip on the Boiler : W and C ; Do this when the thermostat is calling for heat. There shouldnt be much difference between the two readings but there is typically a small voltage drop ; So long as the voltage between W and C is no less than approx. 22 volts ... you are within safe and proper conditions and you can figure you arent loosing an excessive amount of voltage due to loose or poor connections. Hope that helps.
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