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QMark MUH0521 Wiring

8598 Views 4 Replies 4 Participants Last post by  Noodle
Hopefully somebody can help me out. I have a 3-5kw heater above model and its single phase 240v. I have wired it and it won't come on. I also have a marley m602 external 240v line voltage double break thermostat wired to it just like the wiring diagram on the heater shows it and still don't work. I have checked continuity through the overloads and those are ok. The thermostat has 4 wires 2-red for line and 2-black for load. The wiring diagram shows that one black wire goes to h1, one red wire goes to h2, the other black goes to p1 and the other red goes to p2. done all this and nothing. probably something simple hopefully.:furious::censored:. Thanks in advance.
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Does power make it through the thermostat and reach the heater?

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Is the breaker tripped?
Sounds like maybe the thermostat could be wired wrong, since all the Honeywell line-voltage thermostats I use have one black for L1 and one red for L2, also one black for T1 and red for T2.

If not, I'm wondering if one of the factory jumpers on the heating coils is missing or not connected.
Seems like simple diag to me, test for power in to thermostat, check for power out to heater, check for power at heater, check ohms through heater element. "be sure thermostat is set higher than ambient air temp when testing"
Thanks for the replies. I haven't had a chance to go back and check it yet. I talked to an fellow electrician friend of mine and he also suggested to bypass the one contact point in the thermostat. That will be fine to do because its for my father in law and he is using to take the chill out of the garage. I am just confused why it won't turn on with just the breaker as a switch and not even using the t-stat. I have power through the elements and i have ohmed out all the overloads and nothing. The wiring for the tstat says that the reds are line and the blacks are load.
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