Air Management in Hydronic Piping Loops

Air Management in Hot and Chilled Water Piping Loops
Air Management in Hydronic Piping Loops - This is a secondary chilled water pump in a large pump room designated for pumps and piping in a data center. After a few minor tweaks and corrections, these pumps all operated flawlessly. There were very few issues with the secondary pump start-ups.

Unlike the primary pumps where cavitation was encountered on the primary chilled water pumps and the condenser water pumps for the chiller. The diagnosis for the cavitation of the primary pumps and the condenser water pumps was that the loops were not properly purged. This caused those pumps to cavitate.

The secondary pumps, pictured here, did not have that problem. Kudos to the team that purged the loops on this side of the chilled water system.

That was an initial installation issue. It was also a lesson in priming the system to ensure all the air purged from the loop. After all, cavitation in the pumps can cause damage to the pumps. Even after the initial installation purge, it is important to ensure air does not build up in the water piping loop. To do this we need a few devices to help purge the air before it becomes a problem. This will prevent nuisance problems such as hydronic air block in branch circuits of the loop. It will also prevent any damage that may be caused by pump cavitation as a result of too much air in the system.

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Chilled Water Pipe Vibration Isolators | HVAC Piping

Chilled Water Pipe Vibration Isolators
Chilled Water Pipe Vibration Isolators - Vibration isolators protect the chilled water piping from receiving vibrations transmitted through the piping when the chillers are running. The vibrations can create problems not only for the chilled water piping but also for the building’s structure. The vibration isolators reduce or eliminate the vibrations that can be transmitted by the chillers. (more…)

Boiler Components Controls – HVAC Hydronics

Boiler Components - ControlsBoiler Components Controls - All hot water boilers must have an expansion tank. Water expands when it is heated. There must be a place for it to expand so that the pressure in the boiler loop remains constant. Without a hot water boiler expansion tank, the pressures in the boiler loop system would vary wildly.

Most likely, the pressure will exceed the maximum pressures designed for the boiler hot water loop system. This will result in setting off the pressure relief valve. (more…)

Domestic Hot Water Mixing Valve and Domestic Storage Tank

Domestic Hot Water Mixing Valve and Domestic Storage Tank
Domestic Hot Water Mixing Valve and Domestic Storage Tank - This domestic hot water mixing valve offers a way to temper the hot water coming from a hydronic hot water loop and boiler. It is very important to maintain the appropriate and desirable temperatures of water used for domestic water use.

First, you want to maintain a safe temperature so people are not scalded by extremely hot water temperatures. Once the temperature is safe it needs to be reliable. Since the boilers operate or are on standby 24/7 - 365, the availability is there to reliably make domestic hot water on demand. (more…)

Boiler Pipe Insulation – Energy Efficiency

Boiler Pipe Insulation - Energy Efficiency - Richard, I have lots of my boiler pipe under the house in a crawl space and some in the basement, and none of this pipe is insulated. I just bought the house last year and this past winter my gas bill was crazy high. Can I increase efficiency by insulating these pipes and what are some other ways to keep the gas bill lower by optimizing the boiler system?

Thanks and I look forward to your answer……….Bill – Pittsburgh, PA
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Old Bell Gossett Circulator Pump Bearing Assembly

Old Bell Gossett Circulator Pump Bearing Assembly
Old Bell Gossett Circulator Pump Bearing Assembly - This very old Bell Gossett Circulator pump and bearing assembly was found still functioning even after being flooded out several times in a basement. The pump, probably on its last leg, is at least 20 years old and still functioning.

It is unusual for an electric motor to continue to operate after being subjected to flooding. A circulator pump is comprised of an electric motor and a bearing assembly which holds the impeller. (more…)

Boiler Piping Plant Renovation | HVAC Hydronics

Boiler Piping Plant Renovation
Boiler Piping Plant Renovation - Hot Water Boiler Piping for a commercial boiler application. Boiler project being renovated and getting all new DDC controls for optimum hydronic control and efficiency. Boilers are an excellent way of providing good hot water heating to a large building or community.

In this case, new boilers were installed to replace the old inefficient boilers. The piping was rearranged and a hot water boiler economizer preheater added to make efficiency better. New controls were added for remote monitoring and control and to improve efficiency. Lastly, the entire plant got a makeover to make things more reliable, efficient, and modern. (more…)