HWH mercury level sensor

Topic: HWH mercury level sensor (Read 1109 times) previous topic - next topic

HWH mercury level sensor

May 27, 2019, 10:44:14 am

I was wondering about the internal workings of the level sensor. When it's unlevel, does it simply move the mercury to the low side touching a couple of contacts completing a circuit that makes the yellow lights on the control panel light up? Then when the brain decides it needs to check the level it adjusts the air until the light turns off?

Re: HWH mercury level sensor

Reply #1 – May 27, 2019, 11:16:01 am

Sounds likely to me.

Re: HWH mercury level sensor

Reply #2 – May 27, 2019, 11:37:15 am

If you are tempted to adjust it by turning the screws a bit be forewarned that it is very sensitive. Make a very small adjustment, make your coach not level and see what the auto level thinks.

Re: HWH mercury level sensor

Reply #3 – May 27, 2019, 08:41:08 pm

Thanks for the replies. I have messed with it before. Pressing on each of the sides compressing the springs makes the lights come on which makes sense. There's five wires going into it. I would assume that one is some sort of signal wire and the other four tell each of the lights to turn on. Maybe I can find a wiring diagram somewhere to tell which wires are which.

Re: HWH mercury level sensor

Reply #4 – May 27, 2019, 08:53:29 pm

DJ,

This is what our wire color is and what light it lights
WHITE-(GROUND)
YELLOW-LEFT SIDE
BLACK-FRONT
GREEN-RIGHT SIDE
RED-REAR

Mike

Re: HWH mercury level sensor

Reply #5 – May 27, 2019, 09:11:14 pm

Quote from: Pamela & Mike – May 27, 2019, 08:53:29 pm

DJ,

This is what our wire color is and what light it lights
WHITE-(GROUND)
YELLOW-LEFT SIDE
BLACK-FRONT
GREEN-RIGHT SIDE
RED-REAR

Mike

Thanks a lot Mike, that helps a lot. Looks like each side just completes the circuit to ground?

Re: HWH mercury level sensor

Reply #6 – May 27, 2019, 09:22:46 pm

Quote from: DJ and Jane – May 27, 2019, 09:11:14 pm

. Looks like each side just completes the circuit to ground?

That is the way ours works on our '97. When the coach is out of level the mercury switch completes the circuit and shows the light wire a ground. I will see my IT wife can find the manual in the media section and see if it has this info.

Mike

On edit: Here is the manual for our coach HWH 600. The info about the mercury switch is on page 20 Mike said. Your system is most likely different (as you have a tag) but this is a start as to where you need to look in the manual for your coach system.
https://www.foreforums.com/index.php?action=media;sa=media;in=1457
Pamela

Re: HWH mercury level sensor

Reply #7 – May 27, 2019, 09:29:48 pm

Quote from: Pamela & Mike – May 27, 2019, 09:22:46 pm

That is the way ours works on our '97. When the coach is out of level the mercury switch completes the circuit and shows the light wire a ground. I will see my IT wife can find the manual in the media section and see if it has this info.

Mike

Perfect! I was hoping it was something simple like that. The manual would be a big help too.

Re: HWH mercury level sensor

Reply #8 – May 27, 2019, 10:11:40 pm

Quote from: Pamela & Mike – May 27, 2019, 09:22:46 pm

That is the way ours works on our '97. When the coach is out of level the mercury switch completes the circuit and shows the light wire a ground. I will see my IT wife can find the manual in the media section and see if it has this info.

Mike

On edit: Here is the manual for our coach HWH 600. The info about the mercury switch is on page 20 Mike said. Your system is most likely different (as you have a tag) but this is a start as to where you need to look in the manual for your coach system.
https://www.foreforums.com/index.php?action=media;sa=media;in=1457
Pamela

Thanks so much for taking the time to find that for me. I'll check my stuff at the coach tomorrow.

Re: HWH mercury level sensor

Reply #9 – October 24, 2020, 11:42:16 am

I know this is an old topic, but was wondering if anyone might have knowledge of where the sensor is located on a 2001 36' model ?

Re: HWH mercury level sensor

Reply #10 – October 24, 2020, 12:19:45 pm

On my 2000 it was under the pantry as well as on my 2001

Re: HWH mercury level sensor

Reply #11 – October 24, 2020, 02:44:48 pm

Mark, pull out the two drawers under the stove top. The level sensor will be to your right on the floor under the drawers.

This has three screws to adjust what the HWH system sees as level. Each of the screws can be turned in or out a very small adjustment makes a big difference. If you are going to try to adjust it I would suggest marking the current position before you start.

Make an adjustment. Turn the HWH system off and then back on to auto level ad see what it does. All adjustments are very small.

Good luck.

Roger

Re: HWH mercury level sensor

Reply #12 – October 24, 2020, 09:54:07 pm

As we sit at the campground where we evacuated to, was getting bored and started thinking about projects to do. The coach has always just been a tiny tiny bit out of what I feel is perfect level.
Thought about tackling it as a project while we're here.

Re: HWH mercury level sensor

Reply #13 – October 25, 2020, 09:17:29 am

Quote from: MarkC – October 24, 2020, 09:54:07 pm

As we sit at the campground where we evacuated to, was getting bored and started thinking about projects to do. The coach has always just been a tiny tiny bit out of what I feel is perfect level.
Thought about tackling it as a project while we're here.

Dear Mark & Bev,

It's at times like these we need to ask ourselves "How far out of level can we be and still be o-kay?" The way I look at things, the only thing you can do from being "(J)ust been a tiny tiny bit out of what I feel is perfect level." Is make things worse.

But that's only my opinion. My opinion is for you to take the wife, kids and dog for a walk and spend the rest of the day watching a bird hop around on a branch.

Hope your Sunday is going well.

Art & Lynn

Re: HWH mercury level sensor

Reply #14 – October 25, 2020, 09:50:38 am

Perfection is the enemy of good. There is probably a trick to getting the sensor to be "level" when the coach is "level". Turning any of those three screws a 1/4 turn or even less and it is history. I tried adjusting mine and made it worse.

But there is usually something good that comes from everything. I don't use the autolevel anymore. One push on the Air button and you are in manual mode and when you shut the ignition off you stay in manual mode. Level the coach near ride height using a level on the top of the kitchen cabinets or wherever it seems to work. I do that and then make an adjustment a few days later and maybe one more and we sit level enough for a month. Pump doesn't come on (if you don't have leaks) unless you are making an adjustment to raise one end or a side. Most small adjustments can be made by letting some out of the high side.

With an LP refrig you should be within 3 degrees as I recall. A residential refrig is no so fussy. As long as the sliding doors stay closed we are good.

Keeping the Sliding Doors Closed if the Coach is Not Quite Level

I added a 1" square of Velcro at the top edge of each sliding door and a same sized piece at the top of the door frame where it lines up with the door piece. They come together and do what Velcro does and the doors stay closed with no latch required. Use a paper stapler opened up to add a couple staples to help the self stick stuff. The holes are small enough to never be seen if you remove the Velcro squares. You probably won't.

Re: HWH mercury level sensor

Reply #15 – October 25, 2020, 12:38:13 pm

Quote from: Roger & Susan in Home2 – October 25, 2020, 09:50:38 am

Keeping the Sliding Doors Closed

I added a 1" square of Velcro at the top edge of each sliding door and a same sized piece at the top of the door frame where it lines up with the door piece. They come together and do what Velcro does and the doors stay closed with no latch required. Use a paper stapler opened up to add a couple staples to help the self stick stuff. The holes are small enough to never be seen if you remove the Velcro squares. You probably won't.

Slightly off topic but what a great idea. Thanks Roger for another pearl of wisdom.

Richard

Re: HWH mercury level sensor

Reply #16 – October 26, 2020, 12:08:42 am

Okay, I'm convinced ! 99.5% of the bubble is in the center of the level. My thought process was , "Hey, it;s snowing and 10 degrees outside, why not try to make it perfect". After reading comments and watching some football, Its good enough!. Shower drains fine, fridge works great, Wife thinks its perfect, so thats good enough for me.

Thanks to all !

Re: HWH mercury level sensor

Reply #17 – October 26, 2020, 08:04:29 am

My HWH is fairly close when all the lights are off. But I always tweak it manually using a round bubble level set on the cabinet.
Good idea for the sliding doors Roger. I've been locking them closed.

Re: HWH mercury level sensor

Reply #18 – October 26, 2020, 09:21:25 am

Quote from: MarkC – October 26, 2020, 12:08:42 am

"Hey, it;s snowing and 10 degrees outside, why not try to make it perfect".
Thanks to all !

Snowing and 10 degrees outside? I'd flip a coin. Heads: bake some bread, make some onion soup. Tails? Cookies!

Cookies? Communal blanket and two books.

Onion soup with a giant crouton floundering under the weight of some Gruyère cheese broiled to perfection? Movie!

Fiddling with three non-precision wood screws bearing down on a rough casting? Movie.

Re: HWH mercury level sensor

Reply #19 – October 26, 2020, 11:28:57 am

We always leave home with oatmeal raisin and chocolate chip cookie dough made up in advance, scooped into the right sized balls, frozen, vacuumed bagged, six to a bag. When the cookie demand is irresistable we preheat the convection oven, pull out a bag of frozen cookie balls, put them in the oven frozen and 17 minutes later hot perfect cookies. Just enough to satisfy us until next time.

This is a project worth doing every time. Helps keeps us level.

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