LOPI Spirit DV

[cemiii]

I have a gas LOPI in the home I purchased. After a couple years it started acting erratic in starting up. I checked the millivolts from the thermopile to the valve open and closed and they should be fine 470/260. Gas pressure is good .Nice blue pilot flame .So I was sure it must be the gas valve. I bought a new valve and after 2 days of nasty install time, I got it changed out. The new one worked as it should for a couple days and now is operating exactly like the old one. That is, it doesn't start the main burner from either the switch or the thermostat.

Is there something else that could possibly be an issue. The unit clicks when I turn on the remote but does not start. And the red light turns on on the small box that plugs into the wall.

All I can figure is that I got another faulty valve? Any help appreciated.

 

[wooduser]

What is the make and model of your gas valve? You'll find that on the face of the gas valve or the box it came in.

We can look up the specifications for the gas valve and see what the manufacturer wants for millivolts to turn ion the valve.

 

[cemiii]

It is a SIT Nova 820

And I should add that, just like the old one, it works when I tap it with a screwdriver handle (for a while) then goes back to (sticky valve) mode

the valve code is 250-00417 1.6-3.5# Travis Industries 11/29/18

 

[cemiii]

Also can someone tell me what the box with the red LED on the plug cord is? I'm guessing it is a low voltage transformer?

 

[wooduser]

http://www.gdainfo.com/Resource1049...SIT Millivolt Valve Troubleshooting Guide.pdf


This is an exceptionally good manual on testing and operating the gas valve.

The specified minimum millivolts to operate the main burner gas valve is 325 millivolts.when the burner is turned off, and 125 millivolts when the main burner is turned on. You report 470 and 260, so it should operate OK, and that the gas valve is bad since the required power is supplied but the main burner isn't operating reliably.

The link shows a nice picture of how to connect up a voltmeter to test the valve ----you might want to check that and make sure you were testing things properly.

 

[wooduser]

http://www.gdainfo.com/Resource1049...SIT Millivolt Valve Troubleshooting Guide.pdf

This is an excellent list of tests that can be made o9n the gas valve.

The thermopile millivolt check specifies that the main burner gas control should have 325 millivolts to it when the main burner gas is switched off, and a minimum of 110 millivolts when the main burner gas is switched on to operate the gas valve reliably. You report well in excess of that under both conditions, so that implies that the gas valve is bad.

You should check the illustration to make sure that you have your meter connected up properly.


Despite that, the "sticky valve" that you re[port is characteristic of a gas valve that is on the edge of operating, but is low on millivolts to open the main burner gas. You may be losing millivolts through the switch and thermostat ----there is a test for ,millivolt switch loss and I'd do that to see how many millivolts you are losing.

You can also try wiring thtp directly to the main burner gas valve, bypassing the switches to see if that causes the main burner to operate.

 

[cemiii]

Thank you. The thermostat is in the remote so I don't think I can do more than possibly add fresh batteries. The new gas valve was the better part of $200 and is non returnable. The valve works fine with a jumper wire or when tapped with a screwdriver handle. The thermostat does reliably shut off the gas when the temperature set is reached.

I guess I'm stuck for now with manually starting it most times, which is not a giant deal. But we had hoped to sell the home and move shortly. And disclosure of this flaw is not going to help the sale.

I guess I can put in a new thermopile as a last ditch hail mary? Is the ultimate ground on these things through the gas piptng? Could grounding in any way be involved? Low volt transformer?

Frustrating. Hate to buy a second new valve and possibly have the same thing.

 

[cemiii]

The black box with the red led seems to be just a receiver for the remote on off switch not a low v transformer.

 

[wooduser]

The new gas valve was the better part of $200 and is non returnable.

A defective part ought to be returnable to an honest dealer. I'd report the milivolts you have measured and the millivolts required by the specifications I linked to and ask that they provide you with a new part. They are going to return the part to the manufacturer for a replacement in any case.

Provide the dealer with both the millivolts when the valve is turned off, and when it's turned on, just as in your opening post. Of course, you'd still have to struggle with replacing the gas valve again, but that goes with the territory of being your own repairman.

But a bad valve should be on the manufacturer who made it.

Where did you get the new gas valve?

 

[cemiii]

This is embarassing but I'm not sure. I was going to buy it from Fire Parts, had it in my cart,but in viewing their return policy, clearly they state they will not take back any part that has been used. I don't know how you find out if its bad without using it. So I bought from a nearby source.

At any rate I bought from an ebay seller who had a perfect rating and was within 20 miles from me because I was in a hurry. I used a guest sign on and paypal. As a guest the order does not show up in Myebay The guy apparently sold out and is not currently not listed on ebay. I do have the box .and his return address, but no way of contacting other than snail mail.
I suspect I might have got one that was previously returned, though the box date was 11/18.

Live and learn, I guess.

 

[Millbilly]

It works with a jumper wire or a tap? What do you mean by this? Will it work reliably with a jumper wire and no tap? The odds of you having 2 sit820 valves fail back to back is very low. Are your TP readings still 470? Are all wires tight? If it works when you jump it then I'd be looking at your circuitry not your valve. Allthough it could be the valve. I think that the 470mv is on the low side. I think the 325mv referenced above is way to low. I replace them at 450mv.

 

[wooduser]

The erratic operation of the gas valve is characteristic of a valve which has ALMOST enough millivolts to turn on. Tapping on the valve, for example, helps jog the valve and can help it open.


If you work at it, you can probably squeeze quite a few more millivolts out of your system, very likely enough to cause the valve to switch on reliably.

To do that I'd first do the test described in the ling to check for the millivolt drop across the switches

470mv is on the low side. I think the 325mv referenced above is way to low. I replace them at 450mv.

Yabbut the relatively low millivolt output of the thermopile could easily be caused by a dirty pilot. In fact I didn't change out a lot of thermopiles, not until I'd cleaned the pilot, checked millivolt losses across switches and other stuff I'm recommending here. Could be low gas pressure or a pilot adjustment on the gas valve set too low too.

 

[Millbilly]

Thanks for adding that. I do this professionally so forget to add that I would replace a thermopile after checking all that. That being said though if he is measuring mv on the thermo pile leads and getting a low reading then the rest of the wires and switches are irrelevant. And what we have in description of his pilot are blue. What's the cost of a TP after replacing a valve anyways? I'd swap out the TP. Tighten all connections. Jump the terminals on the valve and go from there. If that works then troubleshoot your circuitry. My $.02

 

[wooduser]

Always glad to hear alternative ways of dealing with a problem.

My bias here is to see if sufficient additional millivolts can be developed to operate the gas valve reliably. It appears that it's right on the edge of operating now, a few more millivolts may be all that's needed.

So cleaning the pilot orifice and measuring the voltage drop across the switches are the things I'd check first, before replacing the thermopile. And checking the gas input to the pilot burner to see if more pilot burner pressure would develop more millivolts.

If those things don't get the valve to operate reliably, that's when I'd replace the thermopile.

 

[cemiii]

Thank you for the leads and help. When I took it all apart I cleaned the TP and TH with super fine emery. I cleaned the pilot tube and blew out the unit. So, I doubt its that. I have ordered a new TP Monesson 37D1068 but it will be a few days. It is cheap ($10) but none of the more expensive ones had better feedback or showed obviously higher outputs. I can turn up the pilot, but think I'll wait until I try a new TP. first

The only test I saw for loss seemed to be an ohm test.