Combination gas boiler/instant water heaters

Andy Byrnes

Chris most new installations here in the UK are combination boilers. They are easy to install and are small and compact. But the downsides are as the previous post mentioned . Flow rates can be a problem but some manufacturers are developing boilers with heat stores so they can feed two or three taps at once. Whilst the hot water is in demand there will be no heat to the system so again could cause problems in some installations.

I believe the Baxi boiler is available in North America, Its been available in the UK for some time now and is an excellent example of how good combination boilers can be.

Cheers
Andy.

Christopher Haley

Combination gas boiler/instant water heaters

I recently came across a gas boiler (NTI Trinity) that has an optional heat exchanger that makes it capable of priority on-demand hot water production. Aside from the limit of hot water available from the unit (I think it is something like 5 gpm at 120 degrees)is there any other flaw to this set up? It seems too good to be true or else why aren't any other manufactures doing the same thing?

Mike T., Swampeast MO

There are definitely other boilers that do the same thing.

Very hard water might be a problem, but otherwise there really is no flaw save a production rate that's often too low for larger demands. Don't forget that anytime you have DHW priority, that the boiler isn't providing space heating while making DHW. Usually not a problem, but if your DHW demand coincides with setback recovery, the house won't be heating while you're showering/bathing.