Question about ek1 wood boiler to dhw

masonnewb

Been running the wood boiler for a few years now, been running well. Though the wife would like the hot water to be hot longer, as it is when using oil through the summer months. I'm wondering if I can just plumb a plate exchange at the top of the hot water tank then send the water to heating zone heat exchange at oil boiler. It's a system 2000 ek1 with its own dedicated heat exchange at the boiler. But I know I would get endless hot water if piping prioritizing the hot water before heating the house. I just want to make sure that the storage tank for the hot water that commonly comes with the ek1 will function as I plan. Is there something here that I'm not seeing that may cause any issues? Thank you everyone. This site is the best for this stuff.

hot_rod

is your wood boiler an open unpressurized type?

With any type of boiler a plate HX could be added

You could out the wood boiler hx in series before the EK, let it preheat or if it is fired it carries the load

GroundUp

It's typical to install a plate exchanger in the wood boiler loop in series right before the other one, and preheat the cold inlet to the tank with it.

hot_rod

hot_rod

If you run the wood boiler hot, dhw could exceed 180 from the plate

A thermostatic valve after the plate would temper the supply to the EK, 120- 140F range

We have had solar pre- heat trip the T&P valve on the HW tank if not tempered

Roger

Thank you for your question @masonnewb, and for your posts, @hot_rod .

Here is a drawing indicating how we would recommend wood boiler piping and wiring for a heating professional.

Roger

szwedj

@masonnewb the link to the drawing that Roger posted is for an open system wood boiler that is isolated using a plate heat exchanger from one of our Standard model boilers . We also have some other drawings available for closed systems and/or piped to our Frontier model boiler. You can email me at jszwed@energykinetics.com and we go other your requirements to make sure this is the best drawing for your system that your heating professional can refer to.

masonnewb

@Roger this is the way it is plumbed according to your diagram. The DHW does not stay hot as long as if we were burning oil. I know if I plumb to the hot water tank directly first we would have unlimited hot water. That is what I'm considering. Thank you for the diagram.

masonnewb

@szwedj we have installed according to the diagram and it works well. It just takes a little longer for the water to get hot is the issue. Piping directly to the hot water heater via hx then continue on a series to the hx at the ek . I know the hx at the oil boiler will be redundant…

masonnewb

@hot_rod still trying to decipher what you posted. Not fluent in this . Solar what? Going to figure it out and get back to you.. I hope. Thank you

masonnewb

@hot_rod wood boiler set to 185. Returns to wood boiler at 165. I don't run it too hot though it can get into low 190s.. 192 maybe is usually the high

masonnewb

I'm aware a mixing valve will be needed.

masonnewb

@hot_rod ok I finally figured out your diagram. I like this idea. Thermostatic valve fed by cold water feeding the hx . Check valve before the thermostatic valve at cold water feed .

szwedj

@masonnewb If its' piped and wired per the drawing, you should not see any delay in heating or making hot water. The EK boiler will run as normal if the wood boiler is not up to temperature.

masonnewb

@szwedj I don't run them both. In the winter I only heat with wood.

leonz

https://forum.heatinghelp.com/discussion/comment/1871096#Comment_1871096

Hello masonnewb,

You may want to seriously look at hot water storage to increase the amount of useable hot water if you have room for a storage tank.

There are very large hot water storage tanks that can be passed through a man door that use copper coils for heat exchange. If you have the room, you could use two of them or one very large tank with two separate sets of copper coils for heating and domestic hot water.

szwedj

@masonnewb ok understood. Our set-up marries the two systems allowing the EK boiler to still handle all the zoning and dhw, but use the water heated by the wood boiler if its up to temp and available, and will only fire the burner if when the wood boiler is not to temp. I would think as long as the wood boiler is hot most of the time, the little the EK would need to run would be offset by the convenience of having the hot water that you need?

hot_rod

Without knowing how the wood fired system is tied to the house/ oil boiler it is hard to offer the best solution.

There are any number of ways to pipe this. The plate HXers in series is super simple, does not require any more pumps or control. The wood boiler pre-heats the cold to the EK to whatever temperature the wood boiler happens to be running at.

It could be that simple or this complex. And options in the middle of the road.

masonnewb

@hot_rod it is plumbed according to rogers drawing.