troublesooting lwco mcdonnell&miller pse 801-120

johnnyh13

2 year old boiler lwco worked for 1half season now senses water shuts off boiler many times blinks no water and doesn't fill,when I ground the probe wire from terminal it stays on, waters clean skimmed and no Teflon tape. must be a reason why they have a ground screw on the remote mounted probe, also probe still looks brand new, oil guy said I needed a new control but hade to call someone to verify it.my 2 questions are how can I trouble shoot electronics and how do I know if the probe or control is bad cause I know I can buy separate . been grounding lwco but im scared I am gonna forget to add water and ruin my new peerless boiler steam,any suggestions? nobody has any idea, im not a professional plumber but can fix most anything given time.

nicholas bonham-carter

If you can ground the control, and everything works, wouldn't that indicate the problem is in the probe?
Check the test/reset button, to make sure it is working when grounded to the boiler frame.
That's one thing I like about the old MM float type of LWCO: you know when they work, and when they don't.
How often is water added to the boiler? Too much fresh water can ruin your new Peerless boiler-it just takes a bit longer!--NBC

Abracadabra

What is the feed valve you have connected to the LWCO?

johnnyh13

McDonnell&miller unimatch wfe

johnnyh13

test button says everything works, when I was down there the light came on fast showing no water then shut off fast, another time light was blinking then stopped and kept running with the delay shut off involved, wondering if it needs to be skimmed clear as I cant do this cause of no manuel feed to keep water temp at whatever temp they say I dunno it, but have to clean with bucket many times and next day its a little dirty, if so the probe must be really sensitive.

johnnyh13

also abracadabras posts are not getting through, it says whoops no comment found

wogpa67

The probe could be too close or touching the back of the tee.

johnnyh13

there is no tee it goes inside boiler I think I am gonna have to take off main pressure valve at end of run and put hose into it pushing water from end of run to inside boiler and drain at the same time, I just don't like putting grit into new boiler, any thoughts on this idea, prob will fix my lwco at the same time instead of skimming with no hand water feed possibly cracking cast iron.

Abracadabra

Can you manually feed fine?

johnnyh13

have no manuall feed

johnnyh13

abracadabra guess u did not read posts from the start

Abracadabra

M&M Unimatch WFE has a manual feed button

johnnyh13

how are you gonna skim a boiler holding a button

Abracadabra

johnnyh13 said:

how are you gonna skim a boiler holding a button

wut? who said anything about skimming? I thought we're trying to troubleshoot your lwco problem...

johnnyh13

as I posted be4, there is no tee it goes inside boiler I think I am gonna have to take off main pressure valve at end of run and put hose into it pushing water from end of run to inside boiler and drain at the same time, I just don't like putting grit into new boiler, any thoughts on this idea, prob will fix my lwco at the same time instead of skimming with no hand water feed possibly cracking cast iron. tried it didn't work any way .cleaned and drain boiler many times and had to skim bucket by bucket water is clean but after running short cycling for awhile I see very little black dirt trail in bottom of pail . cycling gets a little better when I do this but not much, done every thing short of changing the whole m and m probe lwco they suck

johnnyh13

tried flushing still no help and troubleshooted lwco except constant volts with meter and water resistance to probe cause I have no meter and all water is spotless, sounds like a car getting ready to stall when lwco light comes on shortcycling at different heating times

johnnyh13

since then added baking soda it has been working as long as ph is less acidic