Dhw with a owb

[homemade]

What are you guys doing for domestic hot water during the summer? Sidearm and plat exchangers are common, but they don’t maintain the temp in the tank. My sister had a new indoor boiler installed and she has a “indirect fired” water heater. So her whole house boiler which is a tankless model, runs hot water threw a coil in the tank. It’s also 309 stainless so no anode rod. Because it doesn’t have a fired heating element the unit should last longer.

So should I go for a tankless water heater for summer use? Just use tee fittings with valves to shut down and one or the other depending on the season?

Then I seen solar water heaters, which uses the the same coil in tank concept as the indirect fired tank, but has an electric or an LP burner built in. Anyone have experience with the solar water heaters?

 

[rancher2]

I run my Garn year around to make my domestic. I have a plate heat exchanger with a Ranco thermostat reading the temp of the water in my LP tank type water heater. The thermostat turns my pumps on and off as needed to keep the water hot in the tank. If I get lazy and don't fire the Garn the LP thermostat will kick the LP burner on.

 

[crowbuster]

water heater. Wasn't worth it for me to run the stove all yr just for hot water. Plus the heat under the kitchen was way to warm where pex runs the floor joists to the indoor boiler. Great in winter not so much in summer.was also a struggle to even keep a fire lit as the cycle times were so long

 

[panolo]

I'm with crowbuster. Power company dang near gives you the huge water heaters that they run on off peak.

 

[NSMaple1]

I have a very good setup here for heating DHW with wood all year long, but I still let the fire go out for the summer and let my plain old electric tank DHW heater do the job for those months. Just not worth it to me - only runs us about $25-30/mo to run it.

 

[homemade]

I’ll be running this past my HVAC and plumber for our new house. I don’t know if our power company does a deduct meter for lower elements on the water heater.

I not only want to be financially efficient, I also want to be environmentally efficient. Fossil fuels won’t last forever.

 

[husqvarna257]

Just my opinion but as others have said the pex running the length of the basement makes the house way to warm. Not only that but the electricity used for the OWB might be around$30 a month. OWB has a circulator running 24/7 and the fan to blow the air in to fire it up. Propane in the off season wins.

 

[homemade]

The owb will be on a separate loop with a plate heat exchanger. Because the stove will have glycol and don’t want to glycol the whole house. The plenum in the forced air furnace, the in floor heat in the garage, and dhw will all be controlled with a zone controller and separate circulating pump. If the Heatmaster wood boiler will allow, I would like that circulator pump to only run “on demand” when a zone calls for heat.

 

[Johnny Yooper]

What are you guys doing for domestic hot water during the summer? Sidearm and plat exchangers are common, but they don’t maintain the temp in the tank. My sister had a new indoor boiler installed and she has a “indirect fired” water heater. So her whole house boiler which is a tankless model, runs hot water threw a coil in the tank. It’s also 309 stainless so no anode rod. Because it doesn’t have a fired heating element the unit should last longer.

So should I go for a tankless water heater for summer use? Just use tee fittings with valves to shut down and one or the other depending on the season?

Then I seen solar water heaters, which uses the the same coil in tank concept as the indirect fired tank, but has an electric or an LP burner built in. Anyone have experience with the solar water heaters?

We have a flat plate exchanger between the outdoor wood boiler and the indoor system; the indoor system has four takeoffs, one is for the 40 gal. hot water tank which is of the internal coil design; an aquastat on the hot water tank signals a small pump to circulate water through the coil inside the tank. I keep the water temperature of the outdoor boiler set to 150F throughout the summer and that keeps us with plenty of hot water.....with three teens in the house there's the constant showers, washing machine and dishwasher running every day, etc., and although I'm running the circulating pump on the OWB loop 24/7 but it would be a helluva lot more $ if I was using propane; we use up the less desirable wood in the wood lot for this purpose and the kids get some exercise gathering it up and maybe even appreciate what goes into turning on a hot water faucet. Operating an OWB just for domestic water in the summer might not be the ticket for everyone, but in our situation, our savings could justify adding a new Husky to the collection every year or two...….. if I could just convince the wifee.

 

[rancher2]

We have a flat plate exchanger between the outdoor wood boiler and the indoor system; the indoor system has four takeoffs, one is for the 40 gal. hot water tank which is of the internal coil design; an aquastat on the hot water tank signals a small pump to circulate water through the coil inside the tank. I keep the water temperature of the outdoor boiler set to 150F throughout the summer and that keeps us with plenty of hot water.....with three teens in the house there's the constant showers, washing machine and dishwasher running every day, etc., and although I'm running the circulating pump on the OWB loop 24/7 but it would be a helluva lot more $ if I was using propane; we use up the less desirable wood in the wood lot for this purpose and the kids get some exercise gathering it up and maybe even appreciate what goes into turning on a hot water faucet. Operating an OWB just for domestic water in the summer might not be the ticket for everyone, but in our situation, our savings could justify adding a new Husky to the collection every year or two...….. if I could just convince the wifee.[/QUOTE]
It is nice to clean up the less than desirable wood in the summer and I haven't bought any propane in ten years.

 

[svk]

Looking to do this with my indoor boiler. How much is a good exchanger? What brands should I look at and/or avoid? Assuming it is just hooked up to the feed into my LP hot water heater?

 

[homemade]

Flat plate exchanger has a higher efficiency rating vs a side arm style exchanger. The exchanger is roughy $100. I’m not sure on brands being better then others. There is three ways to hook them up.
1) pre heat the cold water coming into the water heater and have the LP maintain the temp.
2) circulate the water in the tank threw the exchanger by use of brass circulating pump.
3) there is the passive heating circulating method too. By use of a side arm, natural convection will circulate the water in the tank, but I haven’t seen it work real well.

 

[rancher2]

Flat plate exchanger has a higher efficiency rating vs a side arm style exchanger. The exchanger is roughy $100. I’m not sure on brands being better then others. There is three ways to hook them up.
1) pre heat the cold water coming into the water heater and have the LP maintain the temp.
2) circulate the water in the tank threw the exchanger by use of brass circulating pump.
3) there is the passive heating circulating method too. By use of a side arm, natural convection will circulate the water in the tank, but I haven’t seen it work real well.

I use the number two system and have a Ranco thermostat turn the pumps on and off to maintain the temp. I have 5 flat plate brand heat exchanger's in my system and have had zero problems with them in 10 years.