Ignitor staying on

[spudley]

So the ignitor is staying on in my heater controlled by an older style Honeywell (smart) valve. (SV 9410)

Here's the sequence...turn breaker on, the t-stat calls for heat, inducer starts, ignitor lights, calls for gas, ignites, warms exchanger, fan starts and runs til t-stat is satisfied...but ignitor stays lit the whole time. Even after t-stat no longer calls for heat and turns off the heat, the ignitor stays on until I cut power at breaker.

So I'm thinking a relay in the smart valve must be stuck in a closed position.

Anyone have any ideas or am I buying a new valve?

This is a Hamilton Home Products heater with interchangeable parts to the Modine Hot Dawg.

 

[LS6 Tommy]

If the HSI relay was stuck, cycling the power wouldn't make it shut off. it would come back on as soon as you applied power again.

Tommy

 

[spudley]

If the HSI relay was stuck, cycling the power wouldn't make it shut off. it would come back on as soon as you applied power again.

Tommy

Thanks... and it might be doing just that, but I can't check on it now as the garage is 200 miles away. Going up to play around with it tomorrow.

Should be fun, -8F tonight with 25 mph wind gusts.

By chance do you know if the HSI relay is replaceable?

 

[Jim greengo]

Does it have a seperate board?

 

[spudley]

Does it have a seperate board?

It's got a fan timer board but the ignitor and flame sensor appear to be controlled through the gas valve.

 

[LS6 Tommy]

Thanks... and it might be doing just that, but I can't check on it now as the garage is 200 miles away. Going up to play around with it tomorrow.

Should be fun, -8F tonight with 25 mph wind gusts.

By chance do you know if the HSI relay is replaceable?

I don't think so, at least not on a smart valve and usually not on a separate ignition control board.

Tommy

 

[rlitman]

What's wrong with the HSI staying on all the time? My gas oven works that way, as so many other appliances that don't rely solely on flame sensors. So, are you sure that's not by design?

 

[spudley]

If the HSI relay was stuck, cycling the power wouldn't make it shut off. it would come back on as soon as you applied power again.

Tommy

You nailed it. It's staying on constantly with power applied. So to save replacing a burned out ignitor, I ran a switch thru the ignitor "hot" and now can turn it off while the burners run. I wouldn't have bothered but it's colder than a well diggers *** today so I needed some heat to work.
Cleaned the flame sensor hoping that might be the culprit but no luck.
Looks like I'll be getting a new smart valve. You know, if it was a little smarter there'd be a code for a bad HSI relay.

 

[LS6 Tommy]

What's wrong with the HSI staying on all the time? My gas oven works that way, as so many other appliances that don't rely solely on flame sensors. So, are you sure that's not by design?

Nope. I read the SOO for his gas valve. It should cycle.

Tommy

 

[rlitman]

Nope. I read the SOO for his gas valve. It should cycle.

Tommy

Fair enough. That's how most gas valves on dryers operate, and I'm sure the electrical cost of running the HSI continuously will add up.

 

[bonneyman]

I'm a career long fan of Honeywell products, but their Smart Valves were sketchy from the get-go. Had more problems with those things, especially intermittent electronic issues.

 

[spudley]

I'm a career long fan of Honeywell products, but their Smart Valves were sketchy from the get-go. Had more problems with those things, especially intermittent electronic issues.

I've had to replace the Smart Valve on the home furnace here because of another (electronic) ignitor issue where you had to wiggle the connection at the valve to make contact to get the ignitor to glow. I read where some guys get the position right and shove a match in to keep the connection tight. I couldn't chance a heat failure as I live 200 miles from here so I just replaced it, and it now works fine.

Had a friend who tore one apart and said he found a cracked solder joint on an internal board. He also claimed he resoldered and got it to work again.

When I get my new valve for the garage heater I'll take a look inside the old one.