House not getting up to temp before boiler cuts out

Jdhj09

I have been in this House for about three years now, the boiler was put in maybe five years before I moved in. I have never had an issue with it in the past. This winter i decided to rely a little less on the boiler and heat my home mostly with a wood burning fire/ kerosene heater. All the while I kept my thermostat set to 50 degrees. The boiler would kick on here and there, but nothing like it had in previous winters. The weather got nicer for a while so I turned the thermostat off, then we had a bit of a cold snap (NE Ohio for ya). Any how I noticed that the thermostat was set to 60, yet the temp in the house was somewhere around 50. I thought it was odd so I went down to the boiler (I have a Weil-McLain) and the reset button was flashing so I hit it, the boiler fired up and I thought nothing else about it. I gradually noticed that this problem was persisting and I decided to look deeper into it. It seems as though the HydroStat monitor was shutting the boiler down due to a high temp. (The limit was set to 190) So basically the boiler would fire up and begin circulating to the radiators in the house (they were warming up) then it would reach 190, cut out and the temp would drop. once it dropped below 190 the boiler would kick back on. The boiler reaches the high temp far before the house is heated? I just find it odd because it has never done this in the past. Could it be because of my lack of use? The boiler has an operating high temp of 220, I adjusted the HydroStat to 210. This is allowing the house to reach around 60, yet the temp just keeps rising on the HydroStat so quickly. Is there any quick troubleshooting I can do myself? I want to avoid having a tech come to the house.

Thanks,
Jeff

NY_Rob

Could be a binding rotor on your circulator(s) due to lack of use.

When you make a call for heat- can you hear or feel the circulator running- feel the pipes on either side of the circulator- are they getting hot?

How's your system pressure?

Jdhj09

Yes, they are hot, and the pipes heading to the zones seem to be vibrating as if water is moving though them

Jdhj09

pressure just under 40 psi

John Mills_5

Relief should open at 30 psi Might have gauge trouble. Might measure the supply & return piping and see what the temp difference is. Does sound like a water flow issue.

NY_Rob

Air in the pipes?

STEVEusaPA

210 is way too high for high limit, let alone an operating temperature. It might be steaming.
You could be feeling hot pipes on both sides of the circ just by convection
I would get a separate pressure gauge to check the pressure. If it is at 40psi, shut it off, walk away, call in a pro.
But I would also lean toward the circulator, then check for air, then check control

QasimMohmood

If the boiler is running and heating up and shutting down its doing its job there isn't a problem with boiler operating if your not getting any circulation through it might be the pump it may sound like it running but it could be just the motor running not moving the water I would check the pump for circulation and purge all the zones if you didn't drain water from the boiler and didn't see any leaks any where in the house then it may not be the air problem check the pump if it taco 007 or any water cooled pump it might be bad I would start there. Good luck.

Gordy

The boiler is cycling. Your trying to bring the house from 50 to 60? It will take some time to pick up 10 degrees. In the past when you used the boiler as your sole heat source it only had to maintain set point on a call +\- 1 degree or 2.

Basically the radiation is not giving up the btus faster than they are made at the boiler. So the boiler hits high limit 190, and shuts down until it hits its low differential then fires back up.

This is a tell tale sign that the radiation in place is not large enough to displace the btus the boiler is putting out. My assumption is this is the reason why 190 instead of 180 is the high limit set.

Jdhj09

That makes sense, but why would that change all of the sudden? in past years it has never had an issue...I Have a three bedroom house, two bath rooms, dining room, and large living room...its quite a bit of radiation space....that makes me wonder if it is a circulation issue?

Gordy

How much were you trying to raise the houses set point? Is the system zoned?

If the radiation is hot then that means it is circulating.

Jdhj09

I was at 50 just seeing if i could get to 60 after i raised the high temp limit- the boiler is rated for 220, I set it to 210. The house jumped to 60 relatively quickly. I have two zones- the main house and the living room (an addition in the 80's). I currently set the thermostat to 55, which it is able to maintain without tripping the high limit, and that's fine for my purposes. However i just want to makes sure that there is nothing wrong with the system. I feel if i were to raise the temp to 70, the boiler would temp out before the house..

Gordy

By increasing water temp you increase the output of the radiation.

Unless your radiation is undersized, or you have really long baseboard loops if that is your type of radiation 180 should be fine.

190 may have been chosen to compensate for the afore mentioned.

10 degrees is a big setback to pull out of with out the boiler hitting high limit if the radiation is not ample. I don't know how frequently the boiler was cycling. Or if one, or both zones were running. If one zone only was running that can make cycling happen.

Jdhj09

The more and more I think about it, it sounds like its a circulation issue....Like i said before the radiators are warm, but not not completely hot. Would it be possible for a lesser amount of water to be still circulating? Possibly due to an issue with the pump?

Leon82

There could be debris lodged in the casting of the pump

Jamie Hall

It could easily be a circulation issue. It's also not that hard to check that: remember that the heat output of a baseboard or other radiator is related to the average temperature and the delta T. If your circulation is poor, the delta T will be high -- perhaps remarkably high. If you have adequate circulation, the delta T will be reasonable -- 10 to 20 degrees is kind of normal. It your circulation is wildly excessive then your delta T will be too small. So, take a look at the delta T.

However, my guess in this situation is that you simply don't have enough radiation to recover from a 10 degree setback, which is effectively what you have. You seem to have enough boiler -- if you didn't, it wouldn't cut out (assuming that the circulation is OK -- if the circulation is poor, then the boiler output temp will be way high, but the inlet temp low) -- but if the radiation can't absorb the boiler output, you'll not get warm...

JUGHNE

Sitting idle any air may have gravitated up into the BB. Air lock and water not moving. I would shut down pump and wait and then bleed air from each BB.......maybe??

Gordy

Jdhj09 said:

The more and more I think about it, it sounds like its a circulation issue....Like i said before the radiators are warm, but not not completely hot. Would it be possible for a lesser amount of water to be still circulating? Possibly due to an issue with the pump?

I guess I was interpreting your posts as your radiation is up to temp. Air in the system as mentioned can decrease flow