Are Modulating pumps mandatory?

[hard-work]

A relative has a 15 years old Wilo pump that is on its last legs, being rather noisy. He was told over the phone from a company when getting a quote to replace the pump, that a modulating pump these days has to fitted as the reg's state so. Is that true? Or is this just a recommendation?

His system has an auto bypass valve to ensure water flow through the boiler if the thermo-radiator valves all close down. The hall radiator is where the wall stat is and the radiator has no thermo-valve on it. A modulating pump would be of much use as far as I can see.

thanks.

 

[Dan Robinson]

No - ERP compliant pumps are.

Just get one and lock it on full power fixed speed.

 

[Agile]

Smart pumps and an auto bypass valve are to a large extent not compatible with each other!

 

[hard-work]

No - ERP compliant pumps are.

Just get one and lock it on full power fixed speed.

So, is "No" is an answer for "Is that true?" And "ERP compliant pumps are" is an answer for "Or is this just a recommendation?" Right?

Smart pumps and an auto bypass valve are to a large extent not compatible with each other!

That is what I thought. It would never open the by-pass valve.

 

[Dan Robinson]

No. Modulating pumps are not mandatory. ERP ones are.

Most can be set to a fixed output.

 

[hard-work]

Screwfix sell one only non-modulating pump. All the rest appear to be modulating.
http://www.screwfix.com/p/grundfos-ups2-15-50-60-central-heating-pump/42635

 

[Dan Robinson]

Try reading the manuals.

 

[hard-work]

No. Modulating pumps are not mandatory. ERP ones are.

Most can be set to a fixed output.

Got it! Looking at Screwfix most are ERP compliant variable speed or fixed speeds. But some are not.