# Is it possible to check baseboard heater without supply wires and thermostat?

Discussion in 'Electrical and Wiring' started by vikasintl, Sep 21, 2012.

1. Sep 21, 2012

### vikasintl

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Without connecting thermostat or supply wires..how can I just check the heater if its working... ...is there any way we can check using ohmmeter ...(resistance)...

if its not possible to check without power supply to it...please explain how to connect power to it..without involving thermostat.

2. Sep 21, 2012

### JoeD

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Put the ohm meter across the two wires from the heater and see if there is continuity. You might even be able to find out what the resistance should be by checking the manufactures sight. If not then watts divided by volts should give you a rough idea of what it should be.
If the last test checks out then you should test from each line to ground. It should be open with no connection.

3. Sep 21, 2012

### vikasintl

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Clarification...which two wires I should check ? two wires from the heater means one element wire and other wire in wireway or one end of element to other end of element?

also how which line I should check to ground? element wire and other heater wire which is in wireway?

4. Sep 21, 2012

### Wuzzat?

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If there is heater element continuity then checking either end of the heater to ground is enough.

If you know the heater rated voltage and rated power in watts then the element hot resistance is (V^2)/P and the cold resistance as measured by an ohmmeter is within a few percent of this value.

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5. Sep 23, 2012

### vikasintl

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Ok voltage is 240v and watts is 1500 so..as per your instruction it should be 38.4 ohms

is this for hot or cold?

when I check cold resistance between two ends of element wires...it showed 35.6...is this within range?

6. Sep 24, 2012

### JoeD

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That resistance reading sounds reasonable to me.

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7. Sep 24, 2012

### Wuzzat?

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It depends on what your heater element is made of (possibly Nichrome) and how hot it gets during use and the "temperature coefficient of resistance" for your element.
The baseboard maker probably has a financial incentive to slightly overstate the wattage. Not many people will catch him and even fewer would sue for breach of contract or some such thing.
If you also have an ammeter you can check both voltage and current (about 6A) and determine the hot resistance.

8. Sep 26, 2012

### vikasintl

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Ok thanks...the other heater wire which is in wireway it shows continuity but the reading is only 0.06 at 200 ohms setting...is this ok? or something is wrong?

9. Sep 26, 2012

### JoeD

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If there is no short to ground just plug the damn thing in and try it. You are over thinking this.

10. Sep 26, 2012

### Wuzzat?

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Yes.
If it heats
and does not have the case energized with 120V with respect to ground
and this 120v if it exists is a phantom voltage
and the heater does not trip a breaker
it almost certainly is OK.

I would have measured the element resistance and checked for many, many, megohms from the element to the case, then plugged it in and checked the case for not being energized.
That's Due Diligence and a Duty of Care in my book.

Last edited: Sep 26, 2012

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