Some Lochinvar KHN questions

BlueGreen

I've read about every mod con install manual released in the past 15 years as I am always considering the next boiler to replace my Peerless Pinnacle 140 should it fail. The Lochinvar KHN is at the top of my list but I have a couple of questions on things the manual didn't cover explicitly.

1) Can the KHN be wall mounted or at least neatly attached to a wall while standing for added stability? I don't like how the Pinnacle sits out there with pipes gently pulling every which way. This might be moot as a WHN with 10:1 turn-down will hopefully be out by the time I need one.

2) I have a Tekmar 422/337 setup with three zones of radiant floors (mixed down) and three zones with radiators (boiler/buffer tank temp) modulating the peerless output. With the KHN, I would like to have the 422 tell the KHN what temp to make for central heating and let the KHN handle the modulation. My question is if I configure the KHN to accept the 1-10v BMS input for temperature from the 422 do I lose the ability of the KHN to respond to a DHW call and modulate the temperature as needed? I would prefer this over the way the 422 handles DHW. There are probably other ways to get around this but this would be slick to leave the the BMS (422) to the central heating needs and let the boiler(s) just excuse itself for the occasional DHW call.


Thanks for any input.

Leon82

I think I saw a thread where the guy wall hung it.

bumthun

KHN is floor mount. Lochinvar has not come out with a 10:1 turndown on the WHN, and I haven't heard of them marketing for this.
You can operate your heating side through the 0-10v contacts and BMS, as well as, use the boiler for DHW Priority through the DHW thermostat and tank sensor contacts.

BlueGreen

Thanks for the replies.

Just to clarify, do you think the KHN would use it's own target temperature when in DHW priority, or would the BMS have to provide that?

keyote

Im the guy that wall hung it, manual says best to kep it off ground kind of implying a curb but nowhere specifically saying it can or cant be hung i can lift it up with one arm easilly so wall hung it.I used and angle under and three bolts through the back near the top, total overkill. its a really well made steel cabinet that could be cleverly mounted or secured in many ways, its generously sized so drilling or screwing a bracket, angle, clip, whatever you decide is in no danger of hitting anything.
you can pipe the dhw as zone or into the priority pump terminals, it works best if your tank has a real thermostat so it knows how close its getting rather than a open/ close aquastat i swapped my 50 gal triangle tube aquastat for a lochinvar sensor either way the boiler panel has terminals for tank. in priority you set tank target temps and DHW SWT as well as allowance settings i used 185 swt 120/140 tank target. the boiler tries to meet the demand as quickly as possible so it climbs steadily maintain about a delta 10 and seems to hit 185 almost perfectly seconds before it satisfys the call, sometimes it get up there a bit early and mods between 100 and 95% for the last minute. it can be programmed to run the pump for a bit after shutdown which takes the temp up about 7 more degrees. I find it does well on the high speed of a wilo 3 speed in my triangle smart 50 with 1 1/4'' piping. it really an awesome boiler.
Im not failiar with the tekmar setup you mention but if you want to know will it take different setpoints for DHW and HEATING yes it has actually three heating setpoints and a DHW setpoint, so it will control mixing stations with the other heat temps or you can simply use one DHW SWT and another one heating SWT for the primary loop and let your own mixing controls take it from there, theres also a second tank sensor. Put it this way for anything you might want to program not only can you you can program around that like 3 more contingency parameters as well.they also have a video library at lochinvar university for free registration and for $600 you can get the conxus wifi circuit board and have all the displays and controls of the unit on your mobile or computer. and its got built in bms etc if that your setup. you mention 0-10 v they say that has to be a primary secondary only use controlled by boiler or bms,Im still setting up so hazy on things still i can say i have seen some incredibly precise modulation out of it my computer is noisier. its about waist high and less than a foot deep and about 15 wide. its got 0 clearance back and right side its even got a lot of storage room in it. I wish it had come with the tank sensor, there low water cutoff is expensive but make sure you get one with the correct plug for the board they are hard to source later it will operate without because the included a jumper plug.

keyote

theres a couple pros on here been installing them regularly rich alaska rick paul guys who have used them like them