GSHVBS Vertical Borehole Standard (by GSHPA)

Vertical Borehole Standard (version 2), published by GSHPA, the Ground Source Heat Pump Association

The Ground Source Heat Pump Association (GSHPA) recognises that consultants, installers and consumers require installation standards in order to maintain a high level of installation quality whilst protecting the environment to ensure Best Practice.

The standards are aimed at the designers and installers of ground source systems, architects and engineers specifying ground source systems and main and sub-contractors involved with installer companies supplying ground source systems or designs. The standards should also prove useful for the general public and anybody with an interest in the subject, when considering a ground source installation.

The GSHPA standards are designed to be a concise document providing information for the materials and general specification of a closed loop vertical borehole system. The standards also cover internal pipework up to and including manifolds and/or flushing valves/arrangements. The standards do not include the building entry detail as these will be defined elsewhere. They are not designed to be an installation or training manual and the standards must be referred to in conjunction with recognised design qualifications and training programmes.

The standards are designed to quickly reference minimum materials specification, techniques and qualification requirements and ensure they either comply with the standards (or exceed them) or are employing companies and personnel who do comply with the standards (or exceed them).

Contents:

1. PREAMBLE

1.1 Introduction

1.2 Definitions

1.3 Scoping Work

1.2 Acknowledgements

2. REGULATORY AND GOVERNMENT AGENCY REQUIREMENTS

2.1 Health and Safety

2.2 The Construction (Design and Management) Regulations 2015 (CDM)

2.3 Groundwater Protection – Principles and Practice

2.4 The Coal Authority

2.5 Building Regulations and Other Certification Material

2.6 Planning Permission Requirements

2.8 Notification the British Geological Survey

2.9 Party Wall etc. Act 1996

2.10 Other Codes of Practice and Guidance

3. DESIGN AND INSTALLATION – PERSONNEL AND TRAINING REQUIREMENTS

3.1 Vertical Borehole Ground Loop Designers

3.2 Designers of complex systems

3.3 Designers of simple systems

3.4 Ground Loop Fabricators

3.5 Drilling Contractors and Drilling Equipment Operators

3.6 Site qualifications

4. DESIGN METHODS AND COMPLIANCE

4.1 General Design Approach

4.2 Building Load Data

4.3 Ground Heat Exchanger Desk Study

4.4 Ground Heat Exchanger Design

4.5 Results of System Design Calculation

5. THERMAL RESPONSE TESTING

5.1 In Situ Formation Thermal Response Testing

6. GROUND HEAT EXCHANGER MATERIALS

6.1 Pipe Materials and Tolerances

6.2 Electro-Fusion Fittings: Materials & Tolerances

6.3 Butt-Fusion Fittings: Materials & Tolerances

6.4 Socket-Fusion Fittings: Materials & Tolerances

6.5 Permanent Mechanical Fittings for PE-Xa

6.6 Specific Pipe Application and Dimensional Specification

6.7 Off Site Factory Manufacture and Quality Control

6.8 Pipe and Fittings Sizing

7. PIPE JOINTING, METHODS AND MATERIALS

7.1 Fusion Processes

7.2 Transition Fittings

7.3 Leak Free Installation

7.4 Mechanical Connections

8. GROUND HEAT EXCHANGER GROUT

8.1 General

8.2 Grout Thermal Conductivity

8.3 Grout Hydraulic Conductivity (Permeability)

8.4 Manufacturer / Supplier validation of properties

9. PIPE PLACEMENT AND BACKFILLING

9.1 Piping Material Delivery to Site and Storage

9.2 Header Piping Systems

9.3 Ground Heat Exchanger Loop Protection

9.4 Ground Heat Exchanger Installation

10. FLUSH, PURGE AND PRESSURE TEST OF GROUND HEAT EXCHANGER

10.1 Quality Control

10.2 Purging the System

10.3 On-site Pressure Testing

10.4 Pressure Test Procedure for In Situ Loops

10.5 Integrity of Fusion Joints and Pipe Wall

10.6 Flow Testing of Loops

10.7 Heat Exchanger Flow Testing

11. INDOOR PIPING AND VALVE VAULTS

11.1 Circulator Sizing and System Components

11.2 Valve Vault and Indoor Piping Requirements

12. THERMAL TRANSFER FLUID REQUIREMENTS

12.1 Thermal Transfer Fluid Selection, Use and COSHH Requirements

12.2 Specific Thermal Transfer Fluid Requirements

12.3 Inhibitors & Biocides

12.4 Safety Notices for Thermal Transfer Fluids

12.5 Filling of Ground Loop with Thermal Transfer Fluid

13. DESIGN DRAWINGS AND AS BUILT RECORDS

13.1 Design drawings

13.2 Installation Records

13.3 Re-instatement

14. SUBMITTALS AND ALTERATIONS TO STANDARDS

14.1 Requirement for a Change Process

14.2 Persons or Organisations Permitted to Submit Change information

14.3 Standards Change Process

14.4 Standards Change Review and Outcome

14.5 Dispute of Outcome

14.6 Records of Changes

15. LIST OF REFERENCES AND RECOMMENDED READING MATERIALS