What you can expect to learn from Hot Water Boiler Sequence of Operation Aquastats article: 1) about sequence of operation for boilers 2) basic sequence of operation for the typical boiler 3) boiler controllers and boiler control strategies 4) hot water boiler sequence of operation conclusion 5) lots of resource and related links to help you take a closer look and learn more. (more…)
How Does an Expansion Tank Work – What is an expansion and how does it work? I get that question all the time even though I have written an extensive article on expansion tanks. The two most common expansion tanks you will see in HVAC applications include the bladder type expansion tank and the steel type expansion tank. The steel type expansion tank needs some basic maintenance from time to time to ensure it doesn’t become waterlogged or overfilled which would defeat the purpose of having an expansion tank. For more on the basic maintenance of a steel expansion tank and how to properly fill it check out this article. (more…)
Boiler Circulation Problems | Troubleshooting Hydronic Water Loops – Richard, we have a hot water boiler and we are having problems with the circulation of the water. The radiators are cool and we don’t seem to have good heat. The boiler seems to be working fine but the radiators are cool. Can you give me some insight into my boiler circulation problem? Kate
Pressure Reducer Valves are used for boilers to decrease the pressure supplied to the boiler from the make-up water feed. The make-up water feed originates from the city water source or well water source. The same water source you use for showering, washing dishes and sometimes drinking water depending on the quality. In many case, the pressure reducer valve or PRV is set to 12 PSI on most boilers. This is the pressure needed for many residential and commercial boiler water loops. (more…)
Why Does My Steam Boiler Run Out of Water – All boilers need a constant supply of water from a make-up water source. In a steam boiler system there are vents that vent condensation. The vents can be found on the radiators and throughout the pipe system especially on large systems that serve larger buildings. Venting is limited to a small amount of the entire H2O and steam volume inside the piping and radiators but does need to be replaced. Most of the steam condenses and is returned to the boiler through the return piping system either by gravity or a condensate pump. As the system uses steam it vents the condensation or steam and this displaces water from the steam system that needs to be replaced and the replacement H2O comes from a make-up water source. (more…)
How to Clean Gas Boiler Burners – Before beginning boiler maintenance or repair including cleaning the gas boiler burners on any boiler it is important to follow all safety procedures. Turn off the gas to the boiler at the gas cock located on the gas line and turn off the gas valve on the boiler. Additionally turn off the main power to the boiler at the circuit breaker. (more…)
Boiler Types – There are many different types of boilers in the boiler room today in a variety of heating applications. There are two main categories of boilers among the different boilers and those two categories are steam boilers and hot water boilers. Either of those categories can be fueled by oil, gas, or electric (although electric is uncommon for steam boilers). (more…)
Hot Water Boiler Reset Control – Richard, We are looking at replacing our boiler with a new boiler. The HVAC contractor, I suppose he is the salesman for the HVAC contractor, is trying to sell us what he refers to as a reset control for our boiler. He tells us it will save us more money by making our boiler more efficient. I think I understand how it works but my wife is not entirely sure about it. Can you tell us what you think about a boiler reset control and how it works?
Thanks and we have learned so much from High Performance HVAC. Keep up the good work.
Boiler Stainless Steel Exhaust Flue Stack
This is a photo of a boiler stainless steel exhaust stack which is used for venting corrosive boiler combustion gases. As the flue gases leave the boiler they cool and depending on the dew point of the gas the gas will experience a change of state from a gas to liquid. This liquid is highly corrosive and only special flues like stainless steel vent can be used when this occurs to prevent premature failure of the boiler vent. There are many considerations to consider with a new installation of a heating system and the type of vent to be utilized to vent the gases from the boiler or furnace.
Boiler Circulator Pump – The boiler circulator pump induces the flow of hot water through the boiler and the boiler loop. Usually, the boiler circulator pump is controlled by the aquastat. However, there are various levels of control that can be found that control pumps. One way is by the aquastat as mentioned above. Another way is by an end switch in a zone valve. A thermostat in a particular zone will call for heat and the thermostat calls for the zone valve to open. When the zone valve is fully open an end switch closes the circuit to energize the circulator pump. Typically, the circuit is a control circuit so when the end switch closes it closes the circuit for a relay to energize the circulator pump (more…)