Lochinvar Control Question

Kestrel

Hey wallies - another question - I'm SOOO close to having head and hot water!



I have a tech over right now who is a bit confused about my control scheme, and I'm not sure how to guide him.



The question is this - how to set up the WHN-085 controls.  I have a Grundfos alpha pumping to manifolds that either have radiators with individual TRVs, or to a floor system downstream of a single zone valve that is controlled by a wall thermostat.



The question - how to make the boiler heat up, and boiler circulator spin, in with the only input being the system sensor.  What is the proper setting?

Also, I have the alpha wired to the system bus on the boilers line voltage bus.  Is there a setting to make sure that it always has power to respond to valves that open and close?  Is it WWSD?



Thanks!!!

Mark Eatherton

Good questions...

I'm hoping you meant HEAT and hot water. ;-)



So, other than the one zone that you have that uses a stat and a zone valve, you want to keep the boiler in a hot ready state of operation, ala European style.



If yes, then you will have to put a jumper across the thermostats call for heat on the boiler. Program the WWSD for around 60 degrees F to begin with. You can play with that later.



The boiler should start its boiler pump and burner, and the Alpha is already running.



If you use a System Sensor, you will need to install it (not usually supplied) and wire it into the System Sensor slot. Alternately, you could use the supply sensor and do pretty much the same thing, except that it wouldn't see an increasing demand as fast.



Set the outdoor reset program for whatever you think will work initially (i.e.180 at ZERO outside, and 140 at 60 OSA to start), and you can modify it later as time and experience kick in.



As for the Grundfos, you could wire it into the space heating pump output, and then go into the software for the boiler and set the pump for constant on operation (I'm thinking it requires software, program and cable to do that tho...)



HTH



ME

Kestrel

thanks Mark!

By "jumper across the thermostats call for heat", do you mean connect the TT terminals together?



The boiler came with a system sensor, and I have that plumbed into a well on the system supply side, just upstream of the Alpha.  It's wired to the board, to the 'system sensor' terminals.  Correct?



I think the tech is confused about having nothing wired to the 'heat demand loops' on the lower left of the low-voltage board.

I'm only using the upper right - the outdoor reset, the indirect tank sensor, and the system sensor.

Mark Eatherton

Specifically...

Heat Loop/Demand 1. That is a call for heat.



System Sensor is wired to System Sensor wiring, correct. You need to program the boiler control to recognize it. Factory default is Supply Sensor.



You've got to put a wire onto the the Heat/Demand Loop 1, 2 or 3 in order to get the boiler to fire.





ME

Kestrel

Eureka!

Yes!  That's what we just did - an inch of 20g wire and now my floor loop are hot!

Woohoo!



Factory default is supply sensor - that is what I want.



The only thing harshing my mellow right now is a very slow leak from one of the factory solder joints in the boiler -     Just after the HX there is a T - up to the pressure relief, and down to supply, and there's a little drip-drip-drip from the lower side of that T.  That just bums me the hell out.

Mark Eatherton

May not be a soldered leak....

Sometimes, you have to use paper towels to trace upwards to find the leak. It may APPEAR to be a soldered joint, but may be a threaded leak from above that is showing at the soldered joint. Something may have gotten shook loose in shipping.



The correct Wet Head term is not woo hoo, but instead is FIRE IN THE HOLE :-)



Enjoy. Now, your wife will be yelling at you telling you it is time for dinner, then time for bed, then time to go to work, and on and on... You're hooked ;-)



ME

Kestrel

Au contraire

No, my wife right now is giddy - "The floor is warm!  Take off your shoes - feel this!" is what she's saying.

I presently walk on water, thank you very much.



I'll take some pictures and post them - I'm quite proud of this system.



Alas, however, have to call about warranty service - it is a soldered joint leaking (not one of mine).  Drat.  Also, when the boiler is ramping up and down - say from 20% up to 40%, or down - it make A LOT of noise, coming from the burner blower.  If you hold the cowling, it really settles down.

Mark Eatherton

Congratulations!!

Enjoy your warm floors.



Show us what you've got when you get a chance. Make certain your tech uses a combustion analyzer to check the health of the burner. Also see if he has the PC program to gain access to the adjustable parameters. It makes programming MUCH easier.



Leaks happen to the best of us. As my father use to say, "There are two people in this world that don't have leaks. People who don't solder, and plumbers that do, but lie..."



It comes with the territory.



ME