Frequently Asked Questions

A pressure reducing valve (or pressure reducer) is a valve fitted in a pipe system, which in spite of varying pressures on the inlet side (inlet pressure), makes sure that a certain pressure on the outlet side (outlet pressure) is not exceeded, thus protecting the components and equipment on the outlet side.

A PRV opens and closes an aperture based on the set tension of a spring pushing on a diaphragm. The spring tension is set or adjusted via a plate this relates to a “bar” pressure setting point. Once in operation, the pressure of water pushing on the diaphragm is countered and adjusted by that of the spring.

Pressure gauges can be purchased separately or with the pressure reducing valve.

Yes, the outlet pressure can be adjusted within the spring range by means of standard tools.

No, the pressure reducing valves are described as "fully balanced", this means that varying inlet pressures are compensated by means of the geometry of the valve and thus have no influence on the outlet pressure.

The pressure reducing valve controls the outlet pressure – the inlet pressure has no influence on the control of the pressure.

A static control valve will limit the downstream pressure when there is no movement of water, whereas a dynamic valve control valve will only limit the pressure while there is movement of water.

The specification of the required pressure reducing valve should be checked for its eligibility prior to installation, however, many models are compatible with both supplies.

Pressure reducing valves can be installed horizontally or vertically. If the valve is installed horizontally then the cartridge should be vertically mounted. Consideration should be made with regards to accessing the cartridge for future service/replacement.

A Range of Best Practice Guides and Regulations exist through various Standards agencies, but 2 good reference websites include www.safehotwater.co.uk and www.antiscald.co.uk.

There are two likely explanations: firstly, some of our TMV Range feature anti-tamper caps which free spin. These pop off and the adjustment spindle is directly below. Secondly, the feeds may be cross-connected.

This depends on the legislation attached to the sort of property that is being worked on, however, it is also dependant on how much water the system can provide and how much pressure it is providing it with and the limits of the valve selected for the job.

No, as it is impossible to predict what the Valve will be attached to, please follow the commissioning instructions provided and the desired temperature can be set on installation.

We have TMVs accredited to all of these standards, please ask Sales for the Valve most appropriate to your requirements.

No, as long as the Feeds are correctly orientated for the Valve (IE hot Pipe into hot Inlet etc.) the valve will work equally well, whichever way up it is.

We have noted in the past that certain disinfectant chemicals may wholly or partly remove the lubricant from the thermostatic Mixing Valve. We strongly recommend that the valve is checked for performance after flushing and re-lubricate / service if necessary.

All of our point of use valves feature non-return valves and filters. We also have a range of Group TMVs which have optional Non-Return Valves built into the Unions if required.

Yes, but the normal blended outlet temperature range is disregarded, only a temperature between flow and return incoming temperatures can now be achieved.

Firstly, check that both the Hot and Cold Feeds are providing water to the TMV, if not the TMV may be “Fail-safe-ing”. Secondly, look at the Non-Return valves and Filters to ensure they are not clogged or jammed.

TRVs sense the air temperature around them and regulate the flow of water through the radiator to which they are fitted, they do not control the boiler.

TRVs consist of two main parts, a Thermostatic Head which senses the air temperature around them, and the valve body. Together, these regulate the flow of water through the radiator which they are fitted to. Inside the Thermostatic Head is a sensor containing a wax or liquid material which expands as the room temperature warms up and contracts when it cools down. The sensor is connected, in turn, to a valve seat inside the body which opens as the sensor expands and closes as the sensor contracts. As the TRV opens to allow more hot water from the boiler through the radiator, more heat will be given out by the radiator. As the TRV closes and restricts the flow through the radiator, less heat will be given out by the radiator, however, please note that the TRV does not switch the boiler on/off, it only regulates the flow of the available hot water.

TRVs are designed with a range of temperature settings to allow individual rooms to be maintained at different room temperatures and even allow unused rooms to be switched off, to save energy. However, the TRV can only provide heat to the radiator if the boiler is providing hot water.

Yes, to provide good control and save energy, it is very important that TRVs are mounted in ‘free air’ and not blocked by, for example, furniture, curtains, or enclosed within decorative cabinets. The TRV can only work to the temperature which it can sense so.

Where it is impossible to fit a TRV without it being covered (eg. Decorative Radiator Covers), Caleffi offer a range of remote sensing or remote sensing and control TRVs.

Yes, when installed as part of a complete set of heating controls that include timers and room thermostats, TRVs can provide householders with substantial savings in the major area of energy expenditure, 84% of the energy use in a domestic house is in heating and hot water.

If your TRVs are older than 10 years, you should consider upgrading at least the TRV heads because old TRVs can lose their accuracy and performance over time.

It’s always advisable to check the manufacturer’s instructions, however, most modern TRV are bi-directional.

Nearly all domestic closed systems would be compatible, however, it’s advisable to check actual system expansion needed so as to size the vessel correctly. It must also be noted that certain age radiators cannot be sealed due to pressure issues.

It’s the perfect solution to convert an open vented system to a sealed one, thus removing the risk of storing water in the loft space.

This product is supplied with a 3bar safety relief valve which is normally the standard across domestic installation.

It is acceptable to mount in any orientation, however, Altecnic would always recommend following local building regulations and where possible having the safety relief valve positioned in such a way that debris cannot sit on the valve seat.

Altecnic Reflex heating vessel is grey, however, in the industry heating vessels have been supplied in both grey and red colours.

The sealed system, or “robokit”, provide a one-stop shop for a sealed system, however, it is not always the case that all components require fitting. If you have a combination boiler or a system boiler, the machine already includes an SRV which requires installation, removing the need to install the SRV included in the robokit.

The vessel will require the “pre-charge” testing once a year, this usually forms part of the annual service carried out when the boiler is checked.

Continuous commissioning improves network efficiency by maintaining set points, reducing network drift and reducing costs.

Even where networks are well-designed and properly commissioned before residents move in, heat networks are often left to drift, with performance degrading over time.

This is often not due to a fault in equipment, but rather is due to the accumulation of many small changes in the system over time, for example, maintenance engineers changing one part of a heat network without regard to the effect on the whole.

Guru’s real-world monitoring of heat networks over a three-year period delivered
in collaboration with the UK Government, showed that the cost of heat and carbon
emissions can more than double on a heat
network within three years if action is not taken.

The Guru API supports a range of metering and billing services. providing the freedom to swap to more competitive service providers without changing your infrastructure or disturbing customers.

Technology within the Guru Integrate SATK32 uses 868 MHz wireless mesh communication to ensure high reliability, including in areas where SIM cards won't work due to lack of signal.

The wireless mesh network is more secure than unencrypted wired systems and all data is covered under Guru's ISO27001 certification for cyber security.

Data collected by the Hub III Core helps you meet the Heat Network (Metering and Billing) Regulations 2014, comply with the Code of Practice for Heat Networks, and report against Heat Trust’s customer service and consumer protection standards.

The SATK32 is fully accredited by WRAS and KIWA.

Altecnic/Caleffi offer a full range of WRAS approved air vents for the UK market.

Altecnic/Caleffi offer a size range from ¼” to 1”, and also offer air separation devices from 3/4” to DN150 for commercial applications.

Yes, there are several codes in differing sizes which come complete with a service check valve. Upon removal of the AAV, the check valve closes, meaning the system does not have to be drained if the AAV requires attention.

This will depend on exactly how high the temperature is. Our standard AAV range has maximums of 110-120C depending on model. However, we also offer a solar range which can accept a higher 160C and a glycol mix.

Yes, for example the Robocal range has a maximum of 10Bar, whereas the Maxcal has a pressure rating of 16bar.

Yes, as AAVs collect air rather than separate it from in the system, it is best practice to install these at the high point of the system for the best efficiency.

The purpose of an SRV is to protect a sealed circuit from over-pressure.

In a sealed heating circuit, building regulations state where possible to install the SRV close to the heat source on the flow.

Yes, there are standard SRVs and solar rated versions along with temperature and pressure relief valves (T&P valves).

No, it is indicative to manufacturers, the important information is the pressure rating displayed on the top.

No, removal of the cartridge means the valve is no longer calibrated and will invalidate any warranty.

It is important that the ball valve is used on the medium for which it is intended. In this case no.

The pressure rating correlates to the temperature the valve is seeing, for example at 65C max pressure would be 10Bar, however, at a higher temp of 110C the same valve will be rated at 6Bar.

This is dependent on model size and code type.

No, however, it is always advisable to install the valve with spanner flats closest to the inlet.

Yes, all our ball valves meet and exceed the standard for full bore isolation valves.