munchkin /dhw

Kenny

Does anyone have any input on how to make a munchkin go to high fire when the DHW indirect calls of of a priority relay?

GJack

Chuck Shaw_2

Gregg

The only way to make a Munchkin go to high fire on a call for domestic hot water is to install the Vision 1 system. This system is available to Vision contractors, who have been trained by the factory or by a factory rep. The Vision 1 system involves some slightly different piping methods from the normal primary/secondary piping.

I hope this helps

Chuck Shaw
Technical Support Dept
Heat Transfer Products.

leo g_13

hey chuck

when ya coming to vancouver to give us left coast canucks some training? make sure you let me know, and we'll get together, and i'll try to show you the sights!

leo g

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

Kenny

thanks chuck.....

I called the factory today. My only problem with this issue is that the "old" literature shows the boiler and tanks piped together and there is no adjustment for this. I have two systems that are up and running (and paid for) that don't have vision 1 controllers. They are both runnig out of hot water because the boilers both start low and the tank can't recover. How was this being done before vision 1?

Gregg

jw

My advise...

The earlier munchkins started on hi fire and worked down, the new ones start low and work up over a 5 minute time frame.

My first suggestion would be to use an aquastat with a close differential, so the boiler comes on line sooner in the demand cycle. The other suggestion would be to run the indirect at a higher domestic temp and use a tempering valve to increase the usable quantity of water. Thirdly, a bigger tank. Forth, install the vision and required pump and plumbing (if you are using a SSU tank) These options are in order of least to most expensive I believe.

Chuck Shaw_2

I'd love too.

If the chance comes up, Ill let you know if or when I can be there.

Chuck

Kenny

i called the factory............

on Friday and basically had my intelligence insulted. The answer was that I should become Vision 1 certified or perhaps not install the boiler. My answer was that you shouldn't sell a %$^*! boiler that won't go to high fire without a full blown system control. Is the idea of putting an indirect on priority a new idea? Is the idea of using all of the boiler's capacity to make a lot of hot water a new idea? I don't think so. I have three systems all with super-stor tanks that do not keep up. Now I have to go and buy an expensive system control to make the DHW work? I appreciate your help John but I would have liked some better insight from HTP.

Guy_5

Sorry

I am sorry- I didn't mean to insult your intelligence. The point that I was TRYING to get across during our telephone conversation is that there is more to Vision 1 than a control package. Vision 1 training explains, among other things, the different piping necessary to achieve an immediate run up to high fire WITHOUT compromising the central heat circuit. In other words, if you tried to add Vision 1 to a boiler that was not piped as such, your entire installation could end up not working properly.
I understand that you are caught in the staging of the firing rate of the boiler, but that really should not have a huge effect on its ability to produce hot water. Is there a possibility that the indirect tank is too small for the demand? Does it have the proper flow from the boiler, and adequate piping? I realize that you are looking for an easy fix, but I want to provide you with the BEST fix, not just a superficial one.

Kenny

i understand your point.............

and i appreciate your response but I just find it hard to understand why the boiler is still shipped with the existing literature. I have many other munchkin systems (old style boiler) with indirect tanks that produce plenty of hot water. The boilers I speak of are only serving one bathroom apartments - with basic low-flow shower heads. The piping is done in the exact same way that the literature shows. NOWHERE does it say that you need a Vision 1 control to produce DHW. My wholesaler claims to be one of the largest suppliers of Munchkin boilers and nobody there knew this. I can't honestly understand how you say that this sequence of operation will not affect DHW output. In fairness, I am not knocking the boiler or the new control (as I heard it is great) but I do feel that this must be an issue that comes up?

MDoiron

My Alternative

I suffered through a similar situation. I'm a homeowner/architect in Hull MA in the process of installing a non ferrous system becasue I have a non O2 barrier tube that was installed six years ago. It's been a live and learn system and the Wall has always been a reliable source of good information. The Munchkin is now my boiler of choice, however I had difficulty locating an authorthorzed installer for the Vision 1 control for the DHW. The guys at HTP were very helpful putting me in touch with someone who might be able to do the install. The gentleman was very professional and understood the system very well however, he led me along for 4 weeks and then decided that Hull was to far to come too - after meeting me at my house to size the job for an estimate. I was not happy.

So what to do? I decided to cut the Vision 1 control and DHW out of the boiler side of the system and to purchase an electric tankless water heater instead. You might be cringing at the thought of electric, but Hull has one wind turbine that has reduced our electric rates by 3%. And there are plans on the table to install one and maybe two more with a potential electric rate reduction of 10% to 27%. And with the way the gas rates are going electric is a gamble that I am willing to take. It's not installed yet, but when it is I'll post the results. And then again next January when the system is stressed with the low incoming water temp.

Guy_5

Vision1

You Don't need Vision 1 to produce hot water: The principal idea of Vision 1 is to allow 2 distinct operating temperatures from the one boiler without secondary mixing. It does in fact perform better at making hot water, but it is not the ONLY hot water control. John Wood is correct in saying that perhaps a close differential control would help your situation.
If you had a cold start conventional boiler, you would be facing the same issue that you have now; you are drawing from the indirect tank faster than you can supply hot enough boiler water.

Me_8

Does the vision 1 control only allow 2 different temps and leave how the controler "ramps up" the same ?