what's the proper way to test the voltage to the heater element

[DaveMc]

"Profiles in courage"---by JFK---- was not written about people that agreed with the current pulpit occupant!
Rosie-----Can one of you in the fan club explain why sk 1 is the "ONLY" way to test voltage at the heater?
Serjiocal----In sk 2 is there any instance when the meter would read 110?
Ace---What DOES sk 3 confirm?

[SerjicalStrike]

Rosie-----Can one of you in the fan club explain why sk 1 is the "ONLY" way to test voltage at the heater?

Because if all you want to know is if the element is getting the correct amount of voltage, you need to measure 240v across terminals.

Serjiocal----In sk 2 is there any instance when the meter would read 110?

The way it is pictured, no.   

Ace---What DOES sk 3 confirm?

If you read the text under it, it tells you.  It confirms that some voltage is getting to the heater.  It requires further testing to determine if the heater is getting correct voltage, which is what the original poster is asking how to test. 

[Dr. Spa™ Ret.]

Though it would be EXTREMELY rare, #2 could read 110v if element had a direct short to ground.

#3 goes along with #4, to demonstrate why testing from one individual leg to ground doesn't give any relevant information. Most people don't realize that if you have power going to one terminal of the heater, the electricity will also travel THROUGH the heater, and make the other terminal "appear" to have power.

But then, I have a feeling you already know all of this...    

[Tman122]

I hate electrical work. I'm a framer not a finisher.

[Jacuzzi Jim]

 If the all the switches and sensors are working and it's sending 220v to the heater and the spa is not heating.  It's a bad heater, no 2 ways about it!   End of story..

[SerjicalStrike]

Though it would be EXTREMELY rare, #2 could read 110v if element had a direct short to ground.

In which case the spa should be tripping the breaker and then you would be troubleshooting a different issue 

[DaveMc]

Do you think that maybe you should check the thermostatic control---prior to deciding that the heater is bad?

[Dr. Spa™ Ret.]

This thread is about, "what's the proper way to test the voltage to the heater element". e.g. How do you test the voltage going to a heater element and determine if it's correct.

Causes as to why the voltage may be incorrect is a completely different subject, off topic, and irrelevant to the subject of this thread....how ever, as Jim says, if the element IS getting 220v and not heating, it's a bad element.

[watson524]

Not to stir the pot but I find it hilarious that this was posted on another forum as a "tell me if I'm right about these sketches being goofy" question.... I got a good laugh when I saw that pop up on the other forum I was perusing last nite and today when another unrelated party mentioned the thermostat:

http://www.diychatroom.com/f18/sketch-relevance-212234/

Guess the interwebs aren't so big

[Hot Spring Ace]

Not to stir the pot but I find it hilarious that this was posted on another forum as a "tell me if I'm right about these sketches being goofy" question.... I got a good laugh when I saw that pop up on the other forum I was perusing last nite and today when another unrelated party mentioned the thermostat:

http://www.diychatroom.com/f18/sketch-relevance-212234/

Guess the interwebs aren't so big

I think someone is taking this way too personally.

[watson524]

Just a tad 

[Jacuzzi Jim]

Do you think that maybe you should check the thermostatic control---prior to deciding that the heater is bad?

  Are you talking temp sensors and or the topside controls?   Either way it doesn't matter, if the system is calling for heat and all parameters say ok, it sends 220v to the heater, it doesn't fluctuate in voltage.   In some cases where 220v is lacking to the spa it may only send 110v to the heater, but the system doesn't know that there is only 110v.  It only knows it's ok to send power to the heater.   So again if you check and there is 220 going to the heater, but no heat. It's a bad heater.  If you check and it's only getting 110v then you need to back track from there and find the problem.  Pretty rare that happens but it does.

   In a case of a bad temp sensor, the spa can be set at 100 and the water can be cold. That's because the sensor thinks it's 100 or 101 and does not send power to the heater, thus a cold spa.  Or the spa is 108 and the temp sensor thinks it's only 90 so it keeps calling for heat.  Thus a really hot spa, till it hits 112 and the high limit trips and shuts off power to the heater.   

[Kev B]

 And Dr Spa had it correct in his post and all the rest of you quizzlings never even needed to respond.
 Now...who in here can give the proper way to check a heating element without even having the power on?

[Tman122]

Without power, check resistance. But as I said this gets tricky. Can you tell us what brand of heater? Could be listed as part of the control pac? Can you disassemble it? Get the tube in your hand? Different sizes of heaters have different resistance values and while your getting resistance between the terminals whats the right resistance? Follow?

This might help.

http://www.wikihow.com/Test-a-Heating-Element

[Kev B]

Without power, check resistance. But as I said this gets tricky. Can you tell us what brand of heater? Could be listed as part of the control pac? Can you disassemble it? Get the tube in your hand? Different sizes of heaters have different resistance values and while your getting resistance between the terminals whats the right resistance? Follow?

 Follow??? LOL, I know my trade well, and if you are a professional....you are able to decipher all this out I will presume. One of these days, this forum is going to get a complete novice electrocuted by giving them advise to do something they should never attempt.