Replace High-limit Sensor?

[Mike Hobbs]

I have an in-deck 1999 Marquis Euphoria and it developed a leak earlier this winter. Rather than pull up deck boards in the snow and cold, I figured I'd just wait for spring and keep topping off the water in the mean time. Anyway, the water has run low a couple of times and caused the heat circulation lines to freeze up and the panel would display FLO and/or OH. Previously, I've been able to thaw out the line by pouring warm water into the intake below the filters. This last time, though, it wouldn't budge, so I hooked a garden hose up to a hot water spigot in the garage and directed the water into the intake. Still wouldn't budge. So then I directed it into the heater output. That freed it up, but shortly after, the panel displayed Sn1. Is it possible that I damaged the high-limit sensor by directing hot water into the heater output? I haven't measured, but I'd guess that our hot water is around 150 F.

Thanks,

- Mike

[tumbleweed]

I have an in-deck 1999 Marquis Euphoria and it developed a leak earlier this winter. Rather than pull up deck boards in the snow and cold, I figured I'd just wait for spring and keep topping off the water in the mean time. Anyway, the water has run low a couple of times and caused the heat circulation lines to freeze up and the panel would display FLO and/or OH. Previously, I've been able to thaw out the line by pouring warm water into the intake below the filters. This last time, though, it wouldn't budge, so I hooked a garden hose up to a hot water spigot in the garage and directed the water into the intake. Still wouldn't budge. So then I directed it into the heater output. That freed it up, but shortly after, the panel displayed Sn1. Is it possible that I damaged the high-limit sensor by directing hot water into the heater output? I haven't measured, but I'd guess that our hot water is around 150 F.

Thanks,

- Mike

Yes it is possible. I recently had to replace both sensors in a 2006 Marquis because of ice. Go ahead and replace the sensor assembly.

[VTX1800CMan]

I have an in-deck 1999 Marquis Euphoria and it developed a leak earlier this winter. Rather than pull up deck boards in the snow and cold, I figured I'd just wait for spring and keep topping off the water in the mean time. Anyway, the water has run low a couple of times and caused the heat circulation lines to freeze up and the panel would display FLO and/or OH. Previously, I've been able to thaw out the line by pouring warm water into the intake below the filters. This last time, though, it wouldn't budge, so I hooked a garden hose up to a hot water spigot in the garage and directed the water into the intake. Still wouldn't budge. So then I directed it into the heater output. That freed it up, but shortly after, the panel displayed Sn1. Is it possible that I damaged the high-limit sensor by directing hot water into the heater output? I haven't measured, but I'd guess that our hot water is around 150 F.

Thanks,

- Mike

I doubt that you have hurt the sensor, more than likely the hot water you introduced put the sensor out of its reading range. When this happens you will get the SN1. Once it cools down you should be fine.