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Boiler Pressure/Heat for our 2nd floor

The upstairs of our small cape is much colder than the downstairs. Though I routinely bleed the forced hot water radiators, the ones in the master bedroom are constantly air bound. The oil service man showed me how to turn up the pressure to 20 on the boiler and force the water to that last radiator, but the boiler refuses to maintain that level on a daily basis. Any idea as to how I can make this system work more efficiently would be greatly appreciated.

Re: Boiler Pressure/Heat for our 2nd floor

Normally the water pressure is maintained by a device that has many names. it can be called a prv or watts 1450 or a heatroll or a mueller. what it does is add water when needed. this device maintains a pressure of 12 to 25 lbs. when the pressure drops it open and adds water until the set pressure is reached. that being said. there are many ways that a system can lose water.
1) leaks
2) expansion tank not working and there fore the pressure goes over 30 lbs the safety valve opens and you lose water.
3) cast iron does allow a certain amount of water to escape through the pores of the metal, this is why a cast iron heating system does humidity a house some what.
4) a leaking pressure relief .

i used to replace several heatrolls a month because they do not last long,


Re: Boiler Pressure/Heat for our 2nd floor

After noting the several items that Shack mentioned as possible causes, and the inability of your current service person to solve the problem, I would suggest consulting the Yellow Pages of the phone book under "heating contractors" or "heating service" to bring in at least one more service person that specializes in forced hot water heating systems to see if they can more clearly diagnose & solve the problem at hand---make sure you select one that specializes in forced hot water (hydronic) heating, since this will take an on-site professional who is familiar with forced hot water radiators to find out exactly what is going on in your system that is causing a lack of heat in the 2nd floor bedroom units, and be able to diagnose if you have any pipe leaks or inner pipe corrosion inside the flooring/walls, and if the rest of the components of the forced hot water system are operating properly.

Do you have well water/or local water that has a lot of calcium/minerals (hard water) in the drinking water???------if so, this can cause a lot of havoc with heating systems that rely on forced hot water to deliver hot water to the rads without clogging up the piping.

Another possibility is that the upstairs supply piping to the radiators may not be properly connected to the boiler supply, or the first floor piping circuits-----sometimes the 2nd floor supply hw pipes are added as an afterthought to an existing hw system that previously served only the 1st floor-----this has to be checked out by a qualified service person.

Unless you live in a very high altitude location (rare, like Denver, Colo.) that would affect the elevation of the hot water in your heating system, there has to be some breakdown (leakage, corrosion, blockage) that is preventing the hot water from flowing freely thru the upstairs radiator convectors to heat the rooms---get a pro in there to find out what it is & fix it----any qualified experienced hydronic service person will be able to find & repair this problem.

Also touch base with some of the other forums that deal specifically with forced hot water heating systems:


Finally, go to Google and enter such phrases as "hot water heating cast iron radiators not heating", or "cold bedroom radiators" to summon up additional info.

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