Navien Combi Boiler Review

Introduction:

The Navien NCB 40 is a gas-fired, wall-mounted condensing boiler that is perfect for larger homes with multiple bathrooms. It has a high seasonal efficiency rating of 96% and an ErP A rating for heat and hot water. It also has a generous 7-year warranty.

Features:

• Easy to install
• High quality product
• Affordable price
• 7-year warranty
• Flue can be run up to 20 meters and the boiler can be fitted outside
• Comes supplied with a built-in filling loop and a free wired Opentherm wifi smart thermostat
• Smart thermostat talks, perfect for partally sighted people
• Smart thermostat runs off of the digital communication protocol called OpenTherm and uses load compensation
• Smart thermostat is wired using low voltage bell wire which is easily hidden
• Smart thermostat comes supplied with about 8 meters of bell wire, which supplies the power to the thermostat, so no need for batteries or extra wires
• Smart thermostat has 2 way communication with the boiler, and it has all the boilers operating information too
• Fault codes are shown on the display of the smart thermostat
• You can set the boilers flow temperature, the room temperature, and the domestic hot water temperature all from the room stat
• Smart thermostat is easy to use and easy to set up
• Boiler package seasonal space heating efficiency is 96% making it ERP class A when fitted with the Smart Stat
• Optional outside weather sensor
• Boiler comes with a fly lead, so you just need to add a 3 pin plug with a 3amp fuse
• Boiler comes supplied with a standard horizontal flue

Performance:

The Navien NCB 40 has an amazing domestic hot water flow rate of 16.37 liters a minute at a 35oC temperature rise. It also has a very high turn down ratio of 10:1, meaning the boiler can modulate down to 4Kw from 40Kw. This makes it very efficient and economical.

Build Quality:

The inside of the boiler is all brass and stainless steel. It has a grundfos ErP pump and the same water block that the ideal boilers use, but Navien have located the prv under the boiler, which is a nice touch. Navien use the same flue system as the ideal and Intergas boilers, so it's very easy and familiar to work on. Both heat exchangers are stainless steel and all the internal pipes are also stainless steel.

Quiet Operation:

The Navien NCB 40 is also a very quiet boiler. It has a noise level of just 52 dB, which is lower than the noise level of a normal conversation. This makes it ideal for installation in living areas.

Conclusion:

I am very impressed with the Navien NCB 40 boiler. It is a great option for larger homes with multiple bathrooms. It is easy to install, has a high quality build, and is very efficient and economical. It is also very quiet, making it ideal for installation in living areas. I would highly recommend this boiler to my customers