Tankless Coil Question

[hobbyheater]

I going to give a friend a hand in hooking up a BIO Mass 40 to a 500 gallon propane storage using the " Simplest pressurized system design ".

I have this tank-less coil from my old oil boiler. It was rated at 2 1/2 GPM, but it had constant circulated water flow around it when installed in the boiler. If it is installed into the top of the propane storage, will it still be able to produce an adequate supply of domestic hot water?
Flange even has aqua-stat well.

 

[ewdudley]

I have this tank-less coil from my old oil boiler. It was rated at 2 1/2 GPM, but it had constant circulated water flow around it when installed in the boiler. If it is installed into the top of the propane storage, will it still be able to produce an adequate supply of domestic hot water?

The one in your photos appears to be about the same size as the one I'm using for DHW, which has '7 gpm' stamped on it. I have another about two thirds as big for the hot tub that is stamped '5 gpm', so the 2 1/2 gpm number doesn't jibe with what I've seen first hand or in product literature. I've had very little luck finding any technical information behind the ratings.

At any rate, I set mine up with a circulator to keep my (turned-off) electric tank filled with reserve hot water, but have ended up keeping the tank valved-off since the coil supplies 'unlimited' hot water straight through all by itself with tank temperatures all the way down below 130 degF. YMMV, but I'd bet your friend will be delighted with the performance of the coil you've pictured. A new one that size would go for a couple hundred dollars.

Of course should plan on having a mixing valve on the outlet for safety.

--ewd

 

[hobbyheater]

The one in your photos appears to be about the same size as the one I'm using for DHW, which has '7 gpm stamped on it. I have another about two thirds as big for the hot tub that is stamped '5 gpm, so the 2 1/2 gpm number doesn't jibe with what I've seen first hand or in product literature.

Of course should plan on having a mixing valve on the outlet for safety.

--ewd[/quote]

The boiler that the coil came out of dates back to the mid 70's . You've jogged my memory , the coils output was dependent on the nozzel size of the burner the bigger the nozzle higher the output , and this boiler used the smallest nozzle. So if a flange is made on the propane storage tank , and this coil is inside it should produce lots of DHW ?

 

[ewdudley]

So if a flange is made on the propane storage tank , and this coil is inside it should produce lots of DHW ?

In my experience, for domestic use, where 'lots' means two showers and a clothes washer all at the same time, you betcha. There are some other folks with tankless coils in the top of storage who might be willing share their experience.

Also I believe AHONA and SmokelessHeat build tanks with tankless coil necks fitted to propane tanks, they might be willing to offer advice or opinions.

--ewd

 

[hobbyheater]

In my experience, for domestic use, where 'lots' means two showers and

Lots to my Friend means one shower at a time . He lives alone .

 

[henfruit]

Mark does use them in tanks.WE sold one to a customer in Maine with 2-250gallon tanks stacked. Set it up in the tank at the end at an angle to get the most hottest water.