Boiler is not warming past 140

Hanna007

The whole house is freezing and won’t go warmer than 58 in any of our zones. I checked the boiler temp. Setting and turned it up to 190. We had a zone valve changed recently and maybe he lowered the temp while he was there. This did. It correct the issue. Thermostats are calling for heat but radiators are just warm or low-hot. If the system needs air bled out it usually drives the temp of the boiler way up, which isn’t happening. It’s controls read as though it is calling for heat but doesn’t seem to running constantly like I would expect in this cold weather

Hanna007

It fires up and, from what I see the gas looks ok. It just stops heating at 140ish

Big Ed_4

What Is the high limit set to ? What limit control is being used ?

HVACNUT

Post some pics of the boiler, controls and piping at different angles from about 8 ft away if possible.
If it worked before, it seems like it wasn't properly purged after the zone valve replacement.

Hanna007

Hanna007

Thanks for helping me out. There are some images. The boiler temp is set to 190. If I fiddle with it set it again to 180 or another setting the boiler does start up and heat up a bit more for a minute, then drops back down to 140. I have played with different zones on and off. I feel like there is some setting somewhere that I am missing.

bucksnort

Temperature probe checks out? Otherwise your brain box.

JohnNY

Lower that Outdoor Reset Diff setting to 0 and see what happens.

Hanna007

I reset the temp I reset the temp diff setting and it did make a difference but has not fixed the isssue. The brain box is only a year old. The gas still just shuts off as soon as it hits 140. The temperature will keep going up for a bit which is letting me know the gas was burning pretty hot. I keep fiddling g with the temperature knob and shutting by of the boiler and restarting it as it seems like the most obvious problem but still no fix.

JohnNY

Hanna007 said:

I reset the temp I reset the temp diff setting and it did make a difference but has not fixed the isssue. The brain box is only a year old. The gas still just shuts off as soon as it hits 140. The temperature will keep going up for a bit which is letting me know the gas was burning pretty hot. I keep fiddling g with the temperature knob and shutting by of the boiler and restarting it as it seems like the most obvious problem but still no fix.

Turn the boiler temp dial to just below the max setting. Turn the outdoor reset dial to zero. Leave it alone for a day and watch it.

Hanna007

I did this and it seems to remedy the temperature problem until the burner finally shuts off again. Once it shuts off then it won’t restart until it is below 140, then it stops as soon as it hits 140. 

I took out the sensor and cleaned it off. 

In reading the manual, which was not helpful, it said there is a thermal purge setting that runs the circulator without starting the burner if the boiler temp is higher than 140. It sounds like this was turned off previously and is now functioning? If so, I don’t know why it would shut offf the boiler once it hits 140. There is a hole next to the limit on the control panel that I believe is for an optional jumper wire

bdheat

Did you ever find a solution to this problem? I am having the same issue with the boiler temp not going past 140.

bucksnort

Hanna007 said:

I did this and it seems to remedy the temperature problem until the burner finally shuts off again. Once it shuts off then it won’t restart until it is below 140, then it stops as soon as it hits 140. 

I took out the sensor and cleaned it off. 

In reading the manual, which was not helpful, it said there is a thermal purge setting that runs the circulator without starting the burner if the boiler temp is higher than 140. It sounds like this was turned off previously and is now functioning? If so, I don’t know why it would shut offf the boiler once it hits 140. There is a hole next to the limit on the control panel that I believe is for an optional jumper wire

Did you test the temp sensor with an Ohm meter? Did turning up the reset change things?

BenisCold

I am having this problem. Anyone find a solution??

HVACNUT

BenisCold said:

I am having this problem. Anyone find a solution??

Same boiler and same control?

BenisCold

I found the solution to this problem. There is a malfunction on the control board.

The board was discontinued for this reason and replaced with an updated board with an updated wiring harness. Available at Supply House for $250ish. Installed in 5 minutes. Problem solved. All problems with boiler have gone away.

pecmsg

BenisCold said:

I found the solution to this problem. There is a malfunction on the control board.

The board was discontinued for this reason and replaced with an updated board with an updated wiring harness. Available at Supply House for $250ish. Installed in 5 minutes. Problem solved. All problems with boiler have gone away.

Since 2022?

EdTheHeaterMan

Perhaps you can get together with @radiantheatrookie, They have extra heat they don't need