So I just purchased a house that has a spa. The heater is a Laars lite 2, propane. The previous owner kept everything in great shape. Had the gas company install a tank, checked for leaks etc... So, I took the front panel off read the instructions, got the pilot light on and glowing, turned on the "on" switch and nothing. What blows my mind is, the is NO electrical connection to the heater, none! does not look like there ever was? The front info panel lists voltage as "mini volt" What is this and is it possible that it does not need 110/240? Totally thrown off here.
Laars Lite 2
- Thread starter k95150
- Start date
Millivolt heaters do not have external power. They use a small thermocouple to generate about 500 millivolts from the heat of the pilot flame.
The voltage goes through a series of control switches to operate the gas valve.
The voltage goes through a series of control switches to operate the gas valve.
So I'm not crazy? Lol. This should fire up after the pilot light has been on for a while?
So I jumped the wires from the TH, to the THP and it shut the pilot light off. The pilot light will stay on and stay on forever but the heater will not turn on
Check voltage coming from the pilot generator.
Do you have a picture of the wiring at the gas valve?
Do you have a picture of the wiring at the gas valve?
Here is how to test a milivolt system. You need to have 450+ mv at the gas valve, points D and E, on the red and white wire that leads to your pilot generator. If you do not have that, you will not get the system to fire up.
First make sure you have the pilot lit and it stays lit. Then get a multi meter and set it to milli volts. At that point put one lead on the gas valve on D and then the other on E. You should get a reading of 450+. Anything less than that the system will not respond. *The pilot generator has a red wire and a white wire connected tot he gas valve, Point D and E.
O.K. So I found my volt meter, checked the PP/TH and TH terminal, nothing, 0 volts showing, Tried with dc and ac readings. The pilot light stays on, does this mean the pilot generator is no good?
You need to read it in millivolts (MV). Just because the pilot stays lit doesn't mean it has enough millivolts (MV) to run the system. It just means there is enough voltage there to keep the pilot portion of the valve open.
so, looking at that picture, where am I measuring, and do I use ac or dc setting to measure? Just trying to figure this thing out, lol
That's too low. Maybe a weak pilot or a weak pilot generator. Sometimes the pilot orifice gets clogged.
You should also check the resistance of the control loop to make sure that it's not too high. A bad connection can cause problems. Check the wire connections at each control.
The voltage is enough to power the pilot, but when the gas valve tries to open, the voltage drops too low and the pilot goes out.
You should also check the resistance of the control loop to make sure that it's not too high. A bad connection can cause problems. Check the wire connections at each control.
The voltage is enough to power the pilot, but when the gas valve tries to open, the voltage drops too low and the pilot goes out.