Low frequency noise control of heat pump unit room in Jiaxing residential Water pump house

1. Project Overview
This project is located in jiaxing city, residential owners now have reflected, households in low frequency noise interference, through field investigation, the low frequency noise, the hum of the typical low frequency noise have an, will become very clear in the dead of night, the noise is far beyond the national standards, as does not affect people's normal life, my company offers a effective solution to the noise.

2.Sound source analysis
Ground source heat pump system is a very common system in the air conditioning system in recent years, the noise is usually divided into air fluid noise and solid structure noise, comprehensive analysis, most of the pump room is obvious solid structure transmission noise, vibration energy from the occupants of the housing steel beam, floor, wall and ceiling radiation outward secondary, In this project, the equipment room and the owner's room are very close to each other. Therefore, if the vibration problem is not properly handled, the structural noise will spread very far, which will affect the owner's living.

3. Specification of scheme design
(1) Regulations on Environmental Protection Design of Construction Projects (87) No.002
(2) Social Living Environment Noise Emission Standard GB22337-2008
(3) Regulations on the Management of Environmental Protection for Construction Projects Ordered by The State Council on November 29, 1998
(4) National Urban Area Environmental Noise Standard GB3096-93
(5) "Ventilation and air conditioning engineering construction quality acceptance Code" GB5032-2002
(6) Design Code for Heating, Ventilation and Air Conditioning GBH19-87 (2001 edition)
(7) Code for Fire Prevention in Building Design GB16-87 (2001 edition)
(8) Code for Building Structure Load GBJ50009-2000
(9) "Ventilation muffler Executive Standard" HJ/T16-1996
(10) General Technical Regulations for Welding

4. Noise reduction measures
A lot of noise is transmitted through the air, so everyone's first impression is to solve the problem by isolating the air noise, but the noise transmitted through the structure will be ignored by most people, and the problem is the vibration caused by the structure noise problem, so we must solve the problem of noise from the perspective of vibration.

First of all, the heat pump unit is very close to the owner's room, so it is necessary to use high-quality shock absorbers with high vibration isolation efficiency to reduce the transmission of vibration of the equipment. Due to improper design and installation, the original shock absorber has been overloaded for a long time and completely lost its function. It needs to be replaced. The elastic support needs to be redesigned for the pipes at both ends of the water pump

Secondly, the whole ground source heat pump system through a large number of water pipes and water pump and the owner's home connection, and the water pipe itself is also a medium of vibration transmission, so the main vibration of the water pipe corresponding vibration and noise attenuation. Including the place where the pipe through the wall also needs to do reaming treatment, and the wall to do detachment.

Other equipment, such as water collector and plate changer, also have vibration propagation to the structure, so similar methods are used to solve the problem.