Tankless and Whirlpools

Paul MacDougall

Are there ways to fill a 60 gal whirlpool with a tankless water heater. I would need a close to a 65* temp rise using a valve that passes 7gpm. An architect that we are dealing with would like to save as mush space as possible. Normally we would just go gal for gal, but are there any other possibilites?

Big Will

Two Noritz 7.5 models piped parallel would do that. they will Also give the customer redundancy if one fails they shift the load to the one that is still working. Unless the control fails completely with the internal valve in the open position in that case a ball valve turned off would isolate the trouble maker until it can be repaired. Two normal tankless water heaters piped parallel will produce boat loads of hot water.

Jack

The discussion...

"speed costs money, how fast do you want to go. I figure these jobs with one or two and present the $ to them and explain the "cost vs time". For instance, a Rinnai (which I represent) R75LSi will make +5gpm at tub temp, so it will take 12-13 minutes to fill the tub. For somewhere in the range of double the cost I can save you six minutes. When explained that way, it is amazing how many people find something to do for six minutes.

Home Depot Employee

Excellent advice Jack
The only other difference that plays apart are those that have the sheet flow or water fall fillers that desire the extra fill rate so that these will work properly.

Bill_111

Other Factors (Revised)

Deep water well in Colorado mountains, cold water intake, low (but typical) water flow & 100-gallon whirlpool tub.

Solution needed to provide continual hot water flow to fill tub? Recently installed new very efficient propane-fired 65-gallon Ruud water heater with high recovery...still short.

Bill

Jack

Certainly...

There are modifiers. I've just found it good practice to start with the lowest point of providing the hw required, or at least that will do the job and once that is rejected you can build the system/sale from there. That way there is ownership and acknowledgment (make sure the owner knows too) of the systems requirements and features that need to be fed, like the waterfall faucet.