Radiant heat issues

crs

I have a Weil McClain Ultra 155 boiler with radiant heat with four zones. Seems like I have a couple of issues. One is the boiler is over heating, shutting down, then restarting (short cycling). We've purged the system many times. Put a new expansion tank on, new spirovent, new reducing valve.
My second problem is that not all zones are heating at the same time. When zone one calls for heat it works fine, but if zone two calls for heat while zone one is on, there is no heat on zone two. If zone three calls for heat while one and two are on, then zone one and two heat up, but zone three does not heat.

neilc

and how are the zones controlled?
valves or circulators?
post a distant shot showing your boiler, the pipes around it, and the valving or circulators,
and of any zone control panels,

is this a new issue?

Zman

This sounds like a piping issue. Can you post pictures?

hot_rod

How old is the boiler, did it ever work properly. Those aluminum block boilers need a flushing occasionally, also a good cleaning on the fire side. Does it have glycol by chance

visfarmdeere

What temperature should a Munchkin home boiler be running at?

skiereric

Re: your first problem. What error message is the unit displaying. Is it "Supply greater than return by 58 °F"

crs

Thanks for all the responses! Zones are controlled by Taco circulator pumps. This a relatively new issue on 15 year boiler. Heat exchanger was replaced 5 years ago. No glycol. Not getting any error messages any longer (I'll post error message from about 3 months ago later along with pictures).

Zman

visfarmdeere said:

What temperature should a Munchkin home boiler be running at?

Please start a separate thread, this post has nothing to do with the OP

crs

@neilc @Zman

crs

@skiereric Several months ago I had an error code "9 114 b25" but haven't seen any recent error codes

neilc

I was going to suspect your primary circ not working, and still might, but,
but next I notice the motor orientation on the secondary radiant circs,
they should be horizontal, like your primary,
the way they're vertical they could be getting airbound at the upper bearing,
and those bearings could get very unhappy about that,

crs

@neilc Would it make any difference if I rotated the secondary circulators 180 degrees so the cartridge is on the bottom (assuming I have the space on the back side)?
Is it possible for the primary circulator to be working but not at full capacity or intermittently?

neilc

nope,
180 doesn't do it, now all the crap in your system drops down to those same, unhappy, bearings,
google taco 007 manual,
it says, motors horizontal,
you've got some sweating to do,

Tom_133

Those pumps are not installed correctly, but more than likely not causing your issue. You are either dealing with a bad supply or return sensor if that code persists, or the bigger green pump on the upper left is not doing its job. If the boiler is coming on, staying on, and not error'ing out, I would suggest testing the upper left pump, if its not spinning enough water to keep up with demand for the zones that would cause your issues, but typically that comes with that error you had earlier and lots of them.