Does swimming pool water heater need to be protected with
GFCI breaker (50A)?
The heater(heat pump) is more than 10' from the pool.

Thanks

Mj.
In the States,the pool heater does not need to be GFCI. (2008- NEC) 680.9

680.26(6)(b). bonded and grounded per/instructions.

Even if the code doesn't require a GFCI breaker, is it still worth the extra $100 for better protection?

MJ:

IMHO, I would install GF protection. I don't have any CEC info for you.

An explanation of the benefits to the client, as opposed to the $$ for GF should help if the job costs are considered to be costly.

Well the heater leaks current and a class A gfci won't even hold if the heater is large enough. Class b GF protection does not protect life so how can it work for life protection except that class b can be used where class a is not available? Actually look at rule 68-068 especially subrule 7
So if the heater is within 3 meters and not the other side of a wall then yes GFCI protection is required. If the heater is further than 3 meters then no.