Using a HW heater for a boiler

JoeyD

I'm looking at buying an apartment building where the heat was seperated for all the units. Instead of boilers they used 40 gallon Bradford HW heaters with circulator pumps for heating each unit. How well does this work?



Also are there any particular maintenance or code issues with these?

EricAune

Water heaters not approved for space heating,,,,,,

In MN we are not allowed to use water heaters for space heating unless they are specifically rated for space heating. 



Tank water heaters are not more than about 60-65% efficient,  Some will say they are fine for the application,  I tend to think if you can install a higher efficient applience you are ahead.

JoeyD

What would you do in my situation?

Do you  think they need to be changed out right away?  I have 14 of these to deal with and it would be quite an expense.

One note:  The seller has said that the Bradford water heaters were rated for this application.  He said they are one of a few manufacturers that rate their water heaters for use as a boiler.

Also, If they should be changed. Is there an easy change out to a more efficient type water heater where I can still use the existing circulator and controls?  Or do I need to scrap everything and put in new boilers? 

The heat loads are between 25K and 40K btus per each unit.

kcopp

do your homework...

Call Bradford-White and ask if they are rated to do heating. Sounds like sketchy setup...

A combi boiler would be great. A Embassy  BMS would be on the low end to a Triangle-Tube Excellence on the high end.

JoeyD

I just went to Bradford White's website

And downloaded the installation PDF manual.  It shows how to hook these up for heating. 



You can do it two ways: 

1.  As a closed loop for heating only

2.  As an open loop to feed both a space heater and supply regular hot water.



The set up I'm working with is the closed loop for heating only.  It appears to be relatively simple.

Timco

be safe

Do yourself and your tenants a huge favor and make sure the relief valve (t&p) that came with the water heaters were all swapped out with 30# relief valves. That is a MUST. Otherwise, sounds like efficiency is the only real loss. Rinnai tankless heaters would also work to replace the 40 gal units, but it does not sound like there is a dire, life threatening situation either...just have them checked for proper gas service & venting & combustion / make-up air requirements as well....



Tim 

CMadatMe

There is an Apartment

Complex that we send heaters to weekly to replace heaters that were used in this type of application. They are Bradford White MI-504's. They supply small air handlers and are also doing the domestic hot water. Average life of a water htr. 6-10 yrs. None of the heaters replaced are in the warranty period

Dennis

Water heaters

As a fellow real estate investor, whatever you install keep it in code, and as simple as possible.

Combi boilers are great, but do you really care what your tenants fuel bills are?

If you do, I suggest insulation and new windows first, believe me the tenants will like the windows, and will not care about the heaters. Heck they'il probably leave the windows open all winter anyhow.

Dennis

One other thing!

You may have a technician check the anodes each year or so, the tank will last a lot longer. I have a 30 gallon glass lined Valiant DWH tank going on 30 years, a little bit of service each year goes a long way.

hot_rod

add a 30lb relief

as Tim mentioned but best leave the factory installed T&P in it's place for warranty and liability. It has a 210F temperature limit should the gas valve fail.



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