Microphor LF210- chasing a potential air leak

[Jascherschel]

I believe we are experiencing an air leak in our Microphor air toilet. Thomas pump (which is only 8 months old) used to only run upon flushing. Now it runs in between flushes and seems to be getting more and more frequent - currently about every 25 minutes. I am hoping this may be a lack of maintenance issue - we are just 16 months in to BB ownership.

We are fairly confident we do not have a compressor tank (if we do we don't know where it is). Why would we not have a pressure tank? I'd love to NOT hear that Thomas pump go off (it is so very loud) every time I flush.

Would water in the lines cause the pressure to drop thus causing the pump to run more frequently? I read a mention of draining water from air lines and we have not attempted that, not even sure about how to do so. I'll keep reading manuals and WOG posts.

What would be other common causes?

I am confident we are due for a rebuild of the Air Sequencing Valve (found records for a master service kit in 2011) so I will put in an order to Mullaney. What other parts would be helpful - there was mention of fittings in a recent post so may add those to the list.

Since we are on the road, I would prefer to have all the possible parts needed and on hand when we tackle the repair so as not to be "stranded".

Thanks in advance.