Gas water heater as a mini-boiler?

Unknown

I have a childhood friend who is living in a rather shady (in my opinion) rent to own situation where after renting this peticular home while he works on shaping up his credit to get a mortgage, his landlord would sell him the property.

The house has two gas appliances, a furnace and a domestic water heater. The furnace heats the first floor, and the second floor is unheated, and very cold during Michigan winters.

He would like to avoid putting in a new hot water heating system untill he actually owns the house, so here is my plan to heat his second floor. I dont know if its possible, maybe you all can offer some equipment opinions or advice.

If I use a gas hot water heater as a mini boiler to run at 150 max temperature and pipe an indirect hot water to it as the priority zone, will it hold up for a couple years.

The only wasted equipment is the gas water heater,.. the indirect hot water heater and the baseboard for the second floor zone will both be used when the heating system is redone, at which time he will convert to oil.

I am thinking that the temerature indicator on the gas valve will act as both high and low limit. when the waster in the gas heater is satisfied it is as if it is off on high limit,.. as the indirect calls for heat it opens a zone valze and powers the circulator to satisfy the zone. As the temperature in the gas heater drops below set point the unit will fire untill the water in our gas mini boiler is back up to temperature.

Has anyone ever tried this?

I am aware that the baseboard wont heat as good and the hot water indirect wont recover as quickly with only 150 degree water, but again it is only temporary untill a proper heating system can be installed.

Any insights as to the gas water heater is self? Will this work?

Thanks so much for you help.
- Norm

Mad Dog_2

Yeah don't waste your time or $$$$$

You'd have to run alot more baseboard with 150 water, the water heater should have all the same safeties as a regular boiler, so by the time you did all that, You might as well pipe a small boiler. Besides all that, the "thing" would run non-stop in cold weather and give him a huge gas bill. Do yourself a favor...get a heating pro in there and tell him you want simple and low budget - your best bet. Mad Dog

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Unknown

I think you misunderstand. There wont be any wasted money,.. everything that is bought will be used in the new heating system in two years. We would use his existing water heater, so no need to buy a new one.

As far as driving up a big gas bill,.. we have to consider his furnace already running non stop with such a high heat loss to the unheated second floor.

Piping a small boiler would be a bigger waste in my opinion because it would be in the garbage in two years when he converts to a modern system.

This isnt something I would do in a customers house, but rather trying to help a friend out of a jam for the least amount of wasted money in temporary equipment.

The gas bill issue is a very valid point, but in the scheme of things I dont see how this can hurt more than it could help, but I am very open to constructive criticsm.

- Norm

Larry Weingarten

How about running some...

...ducts up to the top floor? The furnace is likely a bit oversized anyway. You might want to add some method of balancing things so heat goes where you want it. Fix the holes in the floor when you convert to hydronic ;~)

Yours, Larry

Mad Dog_2

Look, Norm I've done lots of experimental......

low budget jobs like that to try to save the people $$$$. 90% of them wind up coming back to bite ya - that's all. Why do things twice. I think Larry may be on to a better idea. Mad Dog

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Jim_47

2nd floor

How many Square feet are we talking about on that 2nd floor?
If its just for a couple of years, you might find electric baseboard cheap and a quick. Electric heat for a small space is sometimes overlooked but if kept at a moderate temp just to keep the chill off, Electric may be the way to go.
I have an insulated bunkhouse for the boys. It costs almost $2.50 a day to heat, but they are never here for more than 5 weeks in the winter. A small price compared to trying to heat a remote building with gas or oil.

Joe Brix

See if AC is in the plans

Might make sense to put ductwork in the attic and tie it into the exsisting furnace downstairs. When you go hydronic, just keep the ductwork for AC and maybe some hydro-air. I wouldn't try to rig up an old WH. You'll also now be producing scalding hot domestic water just to heat the indirect. Drop the money on the ductwork now, not on an indirect.

ED_27

Gas Water Heater

Have done exactly what you are talking about ,2 rooms & bath on 2nd, suppose to be tempoary,but customer like`s it ,SO! Just recently changed out his tank. Got 10 years out of that baby. G-luck , ED !!

Wayne Cooper

Water heater

I am concidering this project for my second floor only using a tankless gas heater with an expansion tank and pump.
Any thaughts about that?

S Ebels

Norm

Here in Michigan, it's illegal to use a water heater of any kind as a heating appliance. The only exception to that rule are the "dual core" models like the Bradford White Combi-core units. These have an internal HX to use for heating purposes. The price of these units when you include installation is nearly what a standard boiler is. I'd shop around a few distributors and see if they have some old stock sitting around. You can find some pretty darn good deals now and again by doing a little checking around.