Why do some of my radiators heat up and others don't?

Marc_2

Hello all. I have no knowledge about home heating, please bear with me. I just had as leak fixed in a 2nd floor radiator directly above the boiler. When the plumbers turned the system back on and bled all of the radiators in the house, I kicked the heat on. They left before the radiators heated up. It's been 8 hours now, and only the radiators in the back half of the house (near the boiler) are heating up. The radiators in the front are not. Even the 2nd floor radiators near the boiler are heating -- so it's not what floor they are on that's determining which ones get hot. It's not very cold out tonight -- probably in the low 40's. Could this be a factor? Does anyone know what's causing this? Thanks, marc

Marc_2

Some of my radiators are not heating up

Hello all. I have no knowledge about home heating, please bear with me. I just had as leak fixed in a 2nd floor radiator directly above the boiler. When the plumbers turned the system back on and bled all of the radiators in the house, I kicked the heat on. They left before the radiators heated up. It's been 8 hours now, and only the radiators in the back half of the house (near the boiler) are heating up. The radiators in the front are not. Even the 2nd floor radiators near the boiler are heating -- so it's not what floor they are on that's determining which ones get hot. It's not very cold out tonight -- probably in the low 40's. Could this be a factor? Does anyone know what's causing this? The ones not heating had no problem before the system was turned off & restarted. Thanks, Marc

Tom Meyer

Trapped air from the refill

Without going into alot of detail as to why, when the system heated up, it probably released more air into the system.

You have two choices.

Call the plumber and tell him what's going on.

Bleed the cool lines yourself, if it's something you feel comfortable doing. But only let out the air. As soon as water starts to come out, turn off the bleeder. You don't want to introduce more air into the system through new makeup water and you certainly don't want to have the boiler low water cutout knock out the complete system if your system doesn't fill automatically.


Tom Meyer
Senior Designer/Trainer
Precision Hydronics
www.precisionhydronics.com

John@Reliable

Marc, how many thermostats do you have,

could be air still in system,or a valve still off (blocking flow to that area) John@Reliable

Howard

sounds like one of my own callbacks. I had shut several valves to isolate the area I was working on then neglected to open one of the valves. No heat in part of the house.

Howard Service Technician Extraordinaire(really I try)

John@Reliable

Howard,

I won't say why I suggested it might be a closed valve,'cause i would never leave one closed hahaha~John@Reliable

Marc_2

Tom - Thank you!! (no text)

Marc_2

Sincere Thanks to you, too Howard (no text)

Marc_2

John, Thanks for responding (no text)

Tom Meyer

Ya think?

Ya think that's maybe why we stick around to make sure everything is running like it's supposed to before we call it a day?

(Or was that just a silly little something I did?)

Tom Meyer
Senior Designer/Trainer
Precision Hydronics
www.precisionhydronics.com

Aidan (UK)

could also be...

ASSUMING it's a hot water heating system, it could be that all the radiator valves have been fully opened. The water will then mostly circulate through the radiators nearest the boiler, whilst those furthest from the boier will get no flow.

The system would then need re-balancing, partially shutting the valves on the most-favoured radiators to increase the hydraulic resistance and so forcing some water to flow through the least-favoured radiators.

Marc_2

Thanks Aidan. I called the plumber back to check it out. He thinks its air in the system -- said he had to leave, but would be back in a couple of hours, and never returned. He'll probably show tomorrow (I'll try caling him again).
Marc