The Glitch & The Fix

RSS

An owner, who has never been satisfied with the performance of his heating system, decides that the boiler must be the root cause of all the performance issues. Not wanting to spend any more than necessary, he makes several calls looking for the lowest boiler replacement price.

Around 25 years ago, I developed a design that sends high-temperature water to a remote manifold for low-temperature floor heating, mixing it with returning water to achieve the optimal supply temperature, regulated by a variable speed pump. Can you identify a problem with this approach or propose a better one?

These are common design pitfalls that may seem effective as they are. Review them and identify changes that could enhance the layout.

When the system was operated, the owner complained of flow problems. The heat emitters in any given zone were only marginally warmed when their associated zone circulator was operating. The owner questioned if another circulator should be installed.

When only the air handler is operating the heat pump is able to supply the 120 ºF water. However, when the floor heating zone and the air handler are operating at the same time and the outdoor air temperature is below 24 ºF the fluid temperature leaving the heat pump can’t climb above 103 ºF. Why is this happening, and what can be done?

Can you spot several details that are either incorrect or missing? Can you propose an alternative design that would accomplish the same goals using less hardware?

A heating contractor is installing two air-to-water heat pumps as the primary heat source in a large home's hydronic system, keeping the existing boiler as backup. However, problems like heat migration into off zones and corrosion of the vent connector suggest design flaws that need to be addressed.

Occupants of a building using a hydro-split air-to-water heat pump are facing slow recovery after night setbacks and inadequate hot water during peak demand. The system, composed of an outdoor and indoor unit, struggles with heating efficiency. What improvements could enhance its performance?

The first photo shows an oil-fired boiler and surrounding details. Take a close look, and make a list of what you would change in this portion of the system.

The photo in Figure 1 shows a non-pressurized outdoor wood-fired furnace connected to a floor heating subsystem via two PEX tubes. It includes a cast iron circulator, a thermostatic 3-way valve for mixing, a bypass linking supply and return tubes, and an "expansion zone" for another floor heating circuit. This setup is in a multi-million dollar home. Are there any potential issues with the installation?