Testing a block heater

[RickB]

My 870 had it in a freeze plug somewheres on the engine...dont remember where. There was a plug that ran down and was zipped tied next to the starter. thats all i remember about it. Whenever i want to know if something electrical is working, i use a clamp on meter. a can get a reading and know in a matter of seconds how many watts its pulling. Been an electrician for 30 years. Old habits are hard to break

That for sure will work, but you still have to split the legs, don't you, say if you have an old analog Amprobe like mine?

 

[grsthegreat]

That for sure will work, but you still have to split the legs, don't you, say if you have an old analog Amprobe like mine?

i have a test block i use, has a male and female end with open wires to place the clamp. like i said, im an electrician and have to deal with loads and current on a daily basis. For anyone else, yes the leads must be separate. test hot leg only.

 

[RickB]

i have a test block i use, has a male and female end with open wires to place the clamp. like i said, im an electrician and have to deal with loads and current on a daily basis. For anyone else, yes the leads must be separate. test hot leg only.

I can see how that test block would be a very useful item.

 

[Pipestone Kid]

I don't have a clamp on meter, so I can't try that--even if I did, the cord on the heater is moulded and would be very difficult to split. I will try "feeling it to see if it gets warm (I can get at it easily). Sound guy- I have a magnetic heater, but I don't know what kind of alloy the pan is, but a magnet will not stick to it. I have a remote set up for the power so I can turn it on and off from the house. (also have a light hooked up to the remote so I can tell if it is on)The extension cord is a 25 foot with #12 wire, so that isn't holding anything back. I will do some more checking and report back.

 

[Toddao]

When I plug in my block heater, I can hear it sizzle, , I know it is working, , can also feel the block but don't have to if I can hear it.

 

[Soundguy]

sounds like a cast aluminum pan.

if you have a meter , ohm out the heating element. it will be low.. but not a short. figure 9-11 ohms 'or so' for say.. a 1500w element...

 

[Pipestone Kid]

sounds like a cast aluminum pan.

if you have a meter , ohm out the heating element. it will be low.. but not a short. figure 9-11 ohms 'or so' for say.. a 1500w element...

Thanks Sound guy--I have a meter,but I won't be checking it for at least a few hours. We have 31 below zero and a wind chill of 44 below, so I think I will sit by the fire for a little longer........

 

[Katahdin]

An infrared heat gun will show the temperature of the engine block rising above the ambient temperature, if its working. You can get them at Harbor Freight for about $30 bucks and they are great for checking woodstove temperatures and other things.

 

[RickB]

An infrared heat gun will show the temperature of the engine block rising above the ambient temperature, if its working. You can get them at Harbor Freight for about $30 bucks and they are great for checking woodstove temperatures and other things.

Another great inexpensive tool whose uses are limited only by the imagination of the owner. Available at HF and many other retailers.

 

[Industrial Toys]

I have never seen a block heater where the engine wasn't warm to the touch after a period of time, usually quite quickly. Most I can hear sizzling immediately!

If it appears to be not working, putting on a clamp-on amp meter is a moot point! I use this for purposes of telling what a heater draws for interest sake. I have a plug and a recepticle with six inches of single conductor wire between them to use the clamp-on meter.

But back to the problem. If it isn't working, it's either a defective cord, or a heater element burned open. Sometimes the heater connections arc, destroying the contacts. You can test the cord with an ohm meter. One side at a time, from plug to socket. If that is good (and it might be intermittent, broken on the inside from flexing or heat) plugging it into the heater, should give you a reading accross your 110 plug, showing the element resistance, some fairly low ohms reading. Wattage = 110 X Current in amps. Amps = 110 / resistance in ohms.