pressuretrol and vaporstat

KC_Jones

So I already know I am replacing my boiler over the spring/summer/fall time frame.  I am starting to get a list of parts together and anxiously awaiting the arrival of Dan's books (i went ahead and ordered the steamy deal last week)!  Anyway my brain has been on overtime between my system and reading this board.  I was thinking about something.  I am leaning towards adding a vaporstat (0-16oz) control on my new boiler and keeping the pressuretrol that comes with it as a backup.  It got me thinking about the wiring on this part of the system.  I am a novice so please feel free to poke holes in my idea.   I know from what I read on here that I should blow down the boiler yearly using isolation valves and a higher boiler pressure.  I also have noticed that I should try and tune my system to run as low a pressure as I think I can get away with.  So what I was thinking was wiring a 3-way selector switch into the pressure control circuit.  This would allow me to select either device or run both at the same time (primary and backup).  I could set the pressuretrol at a pressure to allow blowdown and use the vaporstat as my primary running device.  So when I want to blowdown all I have to do is turn the selector switch to blowdown and I am all set.  Oh and the way I would wire it at least one of the devices would always be active.  Does anybody have any thoughts on this idea?  I do like to tinker with things and that is probably why I thought about this.  Oh I wasn't sure if I should post this here or in the control portion of the wall so I started here.  If I should post this in the control part let me know and I can move it.  Thanks!

Jamie Hall

You can do that...

I would certainly keep the pressuretrol as a backup and get a vapourstat for primary control.  In the overall cost of a new boiler, it's a minor item.



You don't really need a three way switch, though.  All you really need is a switch in parallel with the vapourstat.  If it's open, you're using the vapourstat.  If it's closed, you're not.  That leaves the pressuretrol in the circuit at all times -- which probably isn't such a bad idea anyway.



I would add, however, a valve to close off the vapourstat when you are running at the higher blowdown pressure.  I know they're supposed to take the higher pressure without damage, but... I just don't like to run gauges and pressure controls beyond their calibrated ranges.  Conservative, or something, I guess.

KC_Jones

Agreed on the isolation valve

Yes I did read about adding the isolation valve to protect the gauge and isolate the vaporstat.  Yes I don't necessarily need a 3 way switch, but it's more of a cool factor more than anything...call me a geek.

vaporvac

Ball valve1

I agree that you only need a small ball valve to isolate the Vstat. The pressuretrol should NOT have one. That's what I did anyway. I would also suggest unionsat either end of the pigtails to faciltate cleaning and maintenance, etc.



We recently did all the planning, buying prepping and piping on my new install. If you read through my past posts (especially I hear a Trane a comin'), you can easily glean a zillion great ideas tand quite a few caveats hat people gave me along the way. I asked every question as I was coming from ground zero. I also spent hours on the phone with the tech dept at the various boiler and burner manufacturers. I bought almost everything through Karen at simplyplumbing.com (boiler burners, draft and spill switch, probeLWCO) and the fittings from pexsupply.com



I still think you could do a wet-based boiler. We ended up using an engine lift and it carried my 640lbs boilers like they were paper. I know others have put in their own atmospherics, but I can't say enough good things about these boilers If you plan on keeping the same system for a while, it's worth it.

Colleen

KC_Jones

I understand

The benefits people have posted on here about the wet boilers, but that weight is a real issue.  I have an engine crane, but no way is that ever going to help in my house.  I have to come through the house no outside entrance to the basement.  At the top of my basement stairs is an area about as square as the door opening is wide to work from...it's super tight.  I have seen worse basements and basement access, but not much worse.

vaporvac

I understand...

and not to beat a dead horse, but these new boilers are really tiny. Heavy, but so small compared to my old atmospheric. That was the first thing that struck me...they were really cute if one can call a boiler cute.

KC_Jones

old isn't that old

My old Weil Mclain is from 1982 and is basically exactly like what I will be getting in the new boiler except smaller.  I know this is hard to believe, but my current is over sized by about 50%...shocking I know.  lol  So I have a very good idea about what size and weight I will be dealing with.  Those Wet based boilers are a good bit heavier, but you have intrigued me to at least look at them.  I will do a little more digging and see what I can see.  Oh and no worries about dead horses or anything I appreciate all advice good bad or indifferent.  Thanks!