I have one of the propane gauges in the link below. I had one originally and it seemed to only work for a day or two then would shut off and not allow gas to flow. At first thought it was a bad gauge, so exchanged it for another and this one works the same way. Works for a day or two then shuts off. Is there a trick to using these gauges? Does it shut off because it thinks there is a leak? http://www.walmart.com/ip/Propane-Tank-Gauge/13350316 Thanks.