lapierre hobby releaser problems

[markcasper]

I have 3 of these releasers and this past week I have been having issues with the ??slide valve??? failing to trip. Sap goes down the vacuum line and it gets trapped out and no more sap till you come and reset it. It has been very damp, cloudy, misty, etc this season and its happening in the overnight hours. I have seen the manifold covered with frost when this happens even with temperatures in the mid and upper 30's. I have warmed it slightly with a torch and then things work fine. Is there o rings or something that may be wore out and leaking air where they are not to. Any knowledge would be helpful.

The one releaser has done it the past 2 nights and the other one did it the middle part of last week one night, but the air temp was only about 33 - 34 that night..

[Clinkis]

I have one of these releasers and had issues with it not resetting after it dumped. Sap would then backup. Cleaned and lubed shaft for float and fixed it.

[maple flats]

A few years ago I had similar issues with a double vertical BHR releaser. It turned out I had a small leak around the float control rod. The leak pulling good vacuum, frosted up the works as moist air was sucked thru the leak. Frost built up and blocked one of the flapper valves partially open. Found and fixed the leak and it was no longer a problem.

[markcasper]

Thanks for the info...I stopped and checked on my way home just now from working in town and everybody is still going. I am going to disassemble that horizontal valve on top and check it out. This is where there was frost on the outside, so there has to be some kind of leak.

[maple flats]

A leak will cause a refrigeration effect to happen. That is how it works, force a liquid thru a small orifice with low pressure on the other side, the rapid expansion cools the liquid or even air instantly. Fix the leak and problem will go away.

[DrTimPerkins]

I have seen the manifold covered with frost when this happens even with temperatures in the mid and upper 30's.

Perfect description of what happens when you have a minor leak in that area. It is similar to what used to be called "carb icing", which used to happen in some old autos and in aspirated airplane engines. Happens more in humid conditions. Caused by the venture effect from the small leak resulting in a localized temperature drop, which is why you see it happening even at temperatures even above freezing. Fix the leak and it will stop. Can be difficult to diagnose because the ice may temporarily block the leak, then it'll melt and start leaking again and the cycle repeats.