smart dynamic pressurisation
cost effective
high performance    

Hydrun HY-P (formerly H-Line) a dynamic pressurisation unit and pressurisation vessel using both diaphram-free open tanks or sealed vessels. Hydrun HY-P dynamic pressurisation systems deliver close tolerance control for water fed heating and cooling and HVAC.

Hydrun HY-P

soft-x dynamic pressurisation unit

Hydrun HY-P dynamic pressurisation

What is Dynamic Pressurisation

Traditional pressurisation utilises a pump which just turns on when the pressure is too low and then turns off when the pressure reaches the desired amount. Dynamic pressurisation stops and starts the pumps at varying speeds as and when needed, this has a number of benefits:-

1. It provides active, precise control over system pressure, ensuring efficiency, longevity, and safety compared to passive, static expansion tanks.
2. By maintaining a precise, optimal pressure, these units prevent fluctuations that can cause air ingress, pump cavitation, and overall system malfunction.
3. Dynamic units are significantly more efficient than standard units, (approx. 90% vs. 40%).
4. You don’t need a sealed pressure vessel, which saves money on ongoing tank inspections.
5. Pressure is held in the unit so a smaller open tank can be used, saving valuable space.
6. Reduces oxygen diffusion levels

The future of pressurisation systems

The Hydrun HY-P Pressure system incorporates the latest innovations in the field of pressurisation and expansion, offering significant advantages over traditional systems using diaphragm pressure vessels, not least the absence of expensive ongoing maintenance and inspection tests.

The Hydrun HY-P Pressure Unit  incorporates a motorised valve, soft-start pump and energy saving control functions. Its design minimises pressure variations by maintaining a precise and stable pressure at the lowest possible energy consumption. This eliminates system noise as well as ensuring maximum in-service component lifespan. The H-Line pressurisation unit and expansion vessel has been rigorously tested to demonstrate negligible oxygen diffusion levels comparative with sealed systems.

Ideal for district heating, district cooling, energy networks, commercial HVAC.

The most cost effective and space efficient industrial pressurisation system on the market.

Dynamic pressurisation units with diaphragm-Free expansion vessels

50% space saving in your plant room. Huge plant room space saving by reducing your expansion volume requirement and footprint.

Really easy handling and access to plant rooms. H-Line is light and small enough to carry through a standard doorway by one person.

Traditional diaphragm vessel not required. Option to omit expensive, high maintenance and space hungry diaphragm vessels by using a small open tank, expansion is managed in the unit.

A dynamic pressure system. Close tolerance control reduces electricity use due to reduced pumping demands and ensures precise pressure control and low noise.  

A reliable and robust industrial pressurisation system. Only high quality components from Grundfos, Danfoss and Schneider utilised.

What to do when your Expansion vessel fails

Use a small open tank with a Hydrun pressurization unit.  Call SmartPressure, our team
are on hand 24/7 365 days a year.

How to avoid the written inspection scheme for expansion tanks and associated costs

Use a small open tank with a Hydrun pressurization unit.  Call SmartPressure,
our team are on hand 24/7 365 days a year.

What to do when your Pressurisation unit fails

Call Smartpressure, our team are on hand 24/7 365 days a year. We have a large stock, bespoke
manufacturing capability with extremely short turn around times for delivery.
HL Hydronics Pressurisation units are very reliable, state of the art and highly efficient.

Our team are on hand 24/7 365 days a year.

We have a large stock and bespoke manufacturing capability with extremely short turn around times for delivery.

Find out how we can help you, email or call on

Hydrun HY-P Expansion Tanks

Expansion Tank Specifications
A wide range of open expansion tanks are available for use with HY-P dependent on system pressure, temperature and volume characteristics. Polyethylene (6mm and 10mm wall thickness) and coated steelheavy-duty options. Factory sizing verification included. Instead of using only 40% of the available expansionvolume (traditional diaphragm vessel design) H-Lineuses up to 90% of its tank capacity. This saves significant plant space and coupled to tank lightness and their narrow widths makes HY-P installation very easy and cost effective compared to fitting traditional diaphragm vessels.

Hydrun HY-P Specifications

Model Name
HY-P 40
HY-P 55
HY-P 70
HY-P 90
Article No.(Auto-fill version)
HL1060A
HL1067A
HL1068A
HL1069A
Max. Operating Pressure 
4.0 Bar 
5.5 Bar 
7.0 Bar 
9.0 Bar 
Voltage
230V 1-phase 
230V 1-phase 
230V 1-phase 
230V 1-phase 
Height 
750 mm 
750 mm 
750 mm 
750 mm 
Depth
210 mm 
210 mm 
210 mm 
210 mm 
IP Class 
IP54
IP54
IP54
IP54
Connection 2 - System pipe 
22 mm CU 
22 mm CU 
22 mm CU 
22 mm CU 
Connection 3 - Suction pipe 
DN25
DN25
DN25
DN25
Download the manual PDF

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