Thread sealant or teflon tape on Dometic TV macerator fittings

[jordanbigel]

I'm replacing an old SeaLand macerator pump with a new one - a Dometic TW discharge pump and I'm wondering if there should be any kind of thread sealant on the valve nipples, which for some odd reason have reverse threads (lefty tighty, righty loosy). Whose brilliant idea was that anyway?

I can't tell from the old pump fittings if there was ever any sealant, but I would have to guess none, which makes me quesy (or is that the poop fumes I've been breathing)?

Peg, are you there?? Come in please!

[peghall]

Don't use any sealant because, unlike most sanitation system connections, you'll need to be able to unscrew the valve nipples to replace the duckbill valves every couple of years.

There's a reason (greed) why the valve nipples on the T-Series discharge pump are reverse threaded: The T-Series pump is identical to the VacuFlush S-Series vacuum pump with only two exceptions:

1. the vacuum pump (arguably) needs 4 duckbill valves--2 on the inbound side and 2 on the outbound side..the T-Series pump only needs 2--1 at each end.

2. Price...current list price on the Dometic site for the S pump is $1000...list price for the T-series pump is $523. Reverse threading the valve nipples on the T-pump makes it impossible to just add another valve nipple at each end. I used to advise our customers who needed to replace their vacuum pump to go with the T-Pump. You might have to replace the duckbills a little more often, but you can buy a lot of duckbills for $500.

And btw...this originated with SeaLand Technology. Dometic only doubled the price for both pumps.


--Peggie

[jordanbigel]

Chapter and verse. You are amazing Peg!

THANKS!