Identify flame rollout sensor/safety

Motorapido

Can anybody identify the flame rollout sensor/safety in this picture? I can't find a manufacturer name or part number on it.

Motorapido

If it helps. this is mounted on a Peerless 63 series spark ignition gas fired steam boiler, about 10 years old.

Tinman

Parts are tracked by make, model, and serial number. This is the current 63 parts number. If there is flame rollout, it's imperative you find the cause and correct it.

Motorapido

Thanks. Understood about identifying the cause of the problem, since rollout is very dangerous. I hired a gas pro to diagnose why the burner was not firing during a continuous call for heat from the stat. All systems and safety controls checked out fine, but when he wiggled the wires connected to this rollout sensor, the gas valve immediately turned on. After removing and then reinstalling the spade connectors to the sensor, everything worked properly. Although it appeared to be simply a loose or corroded spade crimp connector, I figured for good measure it might make sense to buy another rollout sensor to either install or just keep on hand.

Jamie Hall

Plain vanilla loose connection. While there's no harm to having a spare hanging around if you can find it when you need it, what does need to happen is to check the connectors for being clean and gripping properly.

Mark Eatherton

These switches are like a light bulb. They are either good, or bad. Never in between. I agree, check the connections. It's not a partial failure issue, and that can be verified with an ohm meter.

ME

unclejohn

Teardrop rollout. Somewhere on it is the letter C followed by a number thats the temp. in centigrade that the switch opens or fails because it's once and done.

ratio

It looks like a one-shot thermal fuse on the underside; not a resettable thermal snap disk that is used on newer equipment. That said, if it comes back when you wiggle the connectors it sure sounds like a crummy connection to me. I don't think that spades are the mostest bestest reliable connection method. I'd replace them before/same time I replace the limit itself.

ch4man

wanna bet Mark E... i just today had a ~25 year old WM VHE today that was having very iirratic main burner drop outs. after many parts by a junior tech we found the fusible link like the one pictured that would drop voltage for just a millisecond. just long enough to confuse the ignition/control board.

rare yes. impossible no

Mark Eatherton

ch4man said:

wanna bet Mark E... i just today had a ~25 year old WM VHE today that was having very iirratic main burner drop outs. after many parts by a junior tech we found the fusible link like the one pictured that would drop voltage for just a millisecond. just long enough to confuse the ignition/control board.

rare yes. impossible no

It is a fusible link, no? I stand by my contention. It's good or bad, because once its blown, it can't un-blow itself. Yours had a bad connection as well.

Bad connections happen on more than just roll out switches.

Also, @ratio, the manually reset-able sensors are meant for the draft hood, not the burner vestibule. If you have gasses rolling out of the combustion tray, you have a very serious condition (blocked flue gas passage ways) that needs immediate attention, whereas an intermittent spilling draft hood is considered acceptable under the code. Not that I or other well seasoned professionals agree with that, but that's what the standard is.

Work safely out there. These machines can KILL you...

ME

Tim McElwain

You can easily get those from Field Controls.

BobC

I look at any crimped connection with suspicion, especially if there is vibration. I've seen factory crimps on unstripped wire right from the factory on equipment that cost millions of dollars. The connection seems good till the crimp loosens just a little bit, if your lucky the connection fails. If your not lucky the connection becomes intermittent.

The only really good connection is a soldered connection but soldering a fuse is iffy at best. A properly made solder connection is very reliable. Crimped connections make troubleshooting easier till they become unreliable.

Bob