Newbie 50 year old BRYANT - help taco valve

bmw_airhead

I think it’s time for a new boiler. Two questions: 1) how does the old green head taco valve work? The newer gold head pushes the valve *in* to open. Seems straight forward. But I can’t determine how the older one opens. 2) boiler has new bell & gossett pump, but circulation seems poor. Inlet from radiators to pump never gets hot, only warm. Also, I’m sure it’s running, but I’ll be damned if I can feel or hear anything that suggests it’s running. 

bmw_airhead

Also re the bell & gossett. It’s drawing .5 amp regardless of being set on speed 1,2 or three. Put my ear to the body of the pump and can hear the faintest… and I mean faint!!… buzz. Buzz does not change when speed switch is rotated. 

mattmia2

I don't think the circulator is working. The end switch on the zone valve may turn it on. Obviously the valve needs to be open for there to be flow.

bmw_airhead

mattmia2 said:

I don't think the circulator is working. The end switch on the zone valve may turn it on. Obviously the valve needs to be open for there to be flow.

Would convection bring the water through the system adequately to heat the home somewhat? Pump is new, less than a year. I guess new things fail too. 

Previous plumber left one zone switch in manual open, and the old green head looks like it’s been out of service for a long time, left in “closed” state. 

mattmia2

you will get some gravity circulation, especially if that was originally a gravity system with the previous boiler.

you could disconnect the circulator and see if it changes. does the burner shut off on high limit? If it is a converted gravity system it may never get hot enough for the return water to be hot before the thermostat is statisfied.

bmw_airhead

mattmia2 said:

 does the burner shut off on high limit? 

The limit switch at the top of the control panel does shut off the burner when gauge gets to 220°. There is 110 V at the pump when thermostat is demanding heat. I will see if anything changes when pump 110V disconnected. Also, could remove pump and do visual check. It seems odd that the amperage draw doesn’t change when I rotate the speed switch. Oh, house was built in ‘72 and boiler is ‘72, so everything is pretty much original. I’m thinking it’s time to replace. Thanks for your ideas, they’ve been helpful. Merry Christmas! 

HomerJSmith

This may give you an idea of the wiring.

This may give you an idea of how it works.

bmw_airhead

Just to sum up, it was the circulation pump that was the culprit. Looks like there was water intrusion. There’s the new pump installed. 

hot_rod

Yeah, I think you are due for a boiler up grade! Looks like signs of flame roll out, corrosion on the top of the jacket, rust at the burner tray, drips on some of the piping.
Is the basement fairly humid? Lots of corrosion on the wiring connections also.
Might want to get a good quality CO detector in the room?

pecmsg

While you have the time get a Manual "J" Heat load loss performed. 160000 BTU's is huge!
Note any issues with hot / cold rooms.
Are you planning on any improvements with the building envelope? They WILL affect the size of the new boiler.
Then find a contractor that knows what they're doing. In a few months redo it!