Boiler (hot water heat) operation basics: This describes the simple things that you can do to help keep your boiler (hot water system) operating well.
Maintain the correct pressure in the system.
To heat your house effectively with a boiler there needs to be proper pressure in the system. The pressure enables the hot water to go up to the upper most radiators in the house. All systems have a pressure gauge located on the boiler. When you look at the gauge it will have markings showing the pressure in pounds per square inch (psi), sometimes it will also be calibrated in feet (ft) or kPa (kilopascals). The needle shows the actual pressure in the boiler. Many boilers will have a mark or a second needle (usually in red) that indicates the optimal operating pressure. For most two story homes the boiler pressure should be at 17-20 psi. This is the pressure that enables the water to travel to the second floor from the basement location of the boiler.
If you don’t have as much heat on the second floor the pressure in the boiler may be too low. Add water to the boiler until it is at 17 psi. If your home has radiators on the third floor, you’ll need to keep the operating pressure close to or at the upper end of the pressure range (20 psi). If the pressure is low, you will get no heat out of the upper most radiators even if they are full of water.
The boiler has safety feature called a pressure relief valve that will discharge water if the pressure in the boiler goes over 30 psi. I have seen a boiler destroyed (not catastrophically, by exploding) when the homeowner filled the system in excess of 30 psi, which ruined the internal seals requiring the boiler to be replaced. This occurred even though the pressure relief valve worked properly. Oops.
If your boiler feed water valve does not close completely or you do not operate it properly it can destroy your boiler. In general; If you have ball valves (lever handle) they are new and will most likely work perfectly. If you have a round handled valve and it looks ancient then well…Call me if you need help doing this. As a plumber, because these valves and immediately adjacent device (backflow preventer) protect your potable water supply, I can repair or replace these as necessary.
Get air out of the system
In some boiler type heating systems, there will be little or no heat if there is air in the system. If you have only one thermostat and heat in some of the radiators, but not all, you may just have air in the system. I can help solve this for you.
You have two thermostats (or more) and no heat in only one area
This usually means you have a minor problem with the controls (most likely a zone valve, possibly a thermostat) and not the boiler. Call me and I can help find a qualified professional to help solve this problem.