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[email protected] poison_1024@yahoo.com is offline
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Default How do I change a PRV on a Weil McLain boiler

On Nov 9, 9:32*pm, "Ed Pawlowski" wrote:
wrote in message

Hi thanks for your reply. *A few more newbie questions. *1) *Where is
the drain. *Unless it's hidden I do not see it. *2) In terms of
purging the system how exactly do you do that? *Thanks.

****************************************

The drain my not be on the boiler but on the piping in the system as it
enters or leaves the loop. Every system is a bit different so look around..
My system has a drain near the floor and a valve on each zone just before
the circulator for the zone.

The heating system will have an air trap and should be self venting. *If,
however, you have a lot of air to get rid on, just slightly crack the drain
valve just slightly while the circulator is running and you'll hear it
sputter as air pockets pass by.


I found it, it's on the floor almost behind the burner. What is odd
is that there are numerous ball valves on the hot water heater and one
heating zone loops - I'm guessing they put them in in case you had a
leak somewhere or had to swap the circulator out or make a repair.
Plus there are three drain gate vales (in addition to the main boiler
drain) - two on the hot water (indirect fired) loop plus one on the
heating line. I'm not sure why there are all of these gate valves
unless maybe you have to blow/flush them out for some reason. It must
be fun trying to drain the boiler with no floor drain with the valve
all the way down at floor level. I hope I can get enough out into a
bucket. I suspect (hope) that I do not need to get all of the water
out to change the PRV especially since I can close off the heating
zone off. Thanks!