You may be considering having a heat pump installed in your home. After all, they are a much greener way of providing your house with hot water and heating. However, before you commit, it is incredibly important to undertake a lot of research on the topic. On this page, we go through heat pump efficiency and temperature – helping you to make the right choice.
Normally, pump curves in data booklets only cover the pump part. Because of this, power consumption, the P2-value, listed in data booklets, only covers power going into the pump (see figure 1). The same goes for the efficiency value, which only covers the pump part (η = ηP). In some pump types with integrated motor and perhaps also an integrated frequency converter, e.g., canned motor pumps, the power consumption curve and the η-curve cover both the motor and the pump. In this case it is the P1-value that has to be taken into account.
Pump Performance Curves
Pump performance curves are important drawings produced by the pump manufacturer. Pump performance curves are primarily used to predict the variation of the differential head across the pump, as the flow is changed. But in addition variation of efficiency, power, NPSH required etc, as the flow is changed, can also be represented on the pump performance curves by the manufacturer.
Finding Balance – Heat Pump Heating Load vs. Capacity
Tom Schroeder is an Application Engineer II at Crane Engineering. He has more than 7 years of experience in the general industry sector. He specializes in the proper selection of fluid processing equipment like pumps, filters, mechanical seals, and mixers.
Coefficient of Performance
The efficiency of refrigeration systems and heat pumps is denoted by its Coefficient Of Performance (COP). The COP is determined by the ratio between energy usage of the compressor and the amount of useful cooling at the evaporator (for a refrigeration instalation) or useful heat extracted from the condensor (for a heat pump). A high COP value represents a high efficiency.
Simple NCBI Directory
Pump curves represent the energy that is put into a system; system curves represent what the system takes out. A system will operate at the point at which these two curves intersect, as long as nothing else changes in the system (such as a valve being closed or partially closed).
How to use read a centrifugal pump curve?
To answer that question, you’ll need to understand how they work. Most brands won’t actually shut off at a certain temperature. Instead, they’ll continue to work, although at a lower efficiency rate. Some will shut off for safety reasons at certain low temperatures, but this is by no means an across-the-board feature.
Zodiac’s Steve Gutai has spent his career educating builders and servicers on the fine points of hydraulics, system design and equipment selection. As he points out here, the first step down the path toward energy efficiency is learning how to read charts that define a pump’s performance characteristics.