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Re: Struggling with MHK2 thermostat install on Mitsubishi Minisplits
Thanks guys. I definitely misread some of the compatibility charts and also wrongly trusted AI about how my system operates with the MHK2 and the Kumo wifi adapter (Ive also added the wifi adapters on my systems). It doesn't help that this also came at a time not to long after they rolled out the comfort app, which appears to have less functionality than the old Kumo app (and all guides/resources still reference the Kumo app). The short of it is, I wasted a lot of time hunting around for advanced settings that my system is not meant to display in the comfort app nor on the MHK2 thermostat. ugh!
Shortly after my post, I ended up getting a response to an email I sent Mitsubishi support. They said my unit has a physical jumper, not function codes/advanced settings in the app or on the MHK2 (which is what you both suggested). I then found Application Note 3048 that Kaos linked above, which confirms it — for my unit you have to cut the jumper to stop the fan.
Thanks for the help all.
papbct
Re: What To Look For When Replacing a Natural Gas Boiler
I can ask around for contractors in SW Idaho. Our Idaho Caleffi rep is a born and raised Idaho gal located near Idaho Falls.
She was a Ferguson branch manager for years, she will know the players in the area.
I know some of the big hydronic knowledgable shops are opening remote branches around the west. Usually around money, resort towns :)
Let me know or PM me the town you are near.
A small wall hung would clean up that room.
hot_rod
Re: Main air vent location
Yup. That's the longest but there are 3 more that are each just under 200'.
Gateacre
Re: Main air vent location
There's no hammer but the boiler needs to run for about 3 hours to get heat to these 2 rads which are at the end of a 270' main. I've rebuild the traps with Tunstall capsules which needed to be done but slows venting even more since they don't vent as quickly as the original trap elements. This system started out burning coal and nobody thought to add mains vents when it was converted.
Gateacre
Re: So fresh water carrying O2 causes corrosion. How about a HOT WATER TANK feeder into the boiler?
Probably much better than your tap water. If it is an open vessel it will still pick up CO2. Dust, mold spores, spiders, whatever is in your air or basement. I doubt the boiler will know or mind.
hot_rod
Re: Makeup water causing boiler failure due to thermal shock
this happened wile i was typing. I'm not sure if people have narrowed down if it is the overheating or the trying to fix the overheating by adding water(or trying to continue to drive it with a leaking cooling system after you've added water). I think it can be both but your best bet is to be patient and let it cool down before adding water.
mattmia2
Re: Main air vent location
This is the end of a 270ft main that starts as 2.5". I like your layout, it's. even easier, thanks
Gateacre
Re: Commissioning new Peerless 63-06
Agreed and you can get them in appropriate scales such as 7-14 pH for better accuracy
https://www.amazon.com/7-0-14-0-indicator-strips-100-box/dp/B001TQOOR4
Re: Boiler Protection with 3-way valve?
I'm a bit biased working for Caleffi, but the 280 is an excellent valve for boiler protection. High Cv, union connections, temperature gauge wells, multiple temperature sensors available.
We sell many of these around the world. They are standard equipment on most wood fired and pellet fired equipment to prevent cold operation which leads to creosote formation. So the manual talks about that type of equipment.
Regardless if you use a valve or electronic solution, the boiler needs to operate to maintain that temperature.
But with a protection valve, shut the boiler off, after the heat call cold start will lengthen cycles and boost boiler efficiency compared to short, under 10 minute cycles.
The type of heat emitters matters, copper fin tube rarely need boiler protection.
Cast rads or large high water content, like gravity conversions, really need protection.
Combining zones helps eliminate shoulder season short cycling. But zoning is a selling feature of hydronics :) catch 22.
In mild conditions it will be hard to eliminate short cycles without maybe tricking the boiler with a anti cycle timer for example. Holding the boiler off when there is a call for heat has some consequences. Comfort might be higher on your list that absolute energy savings?
These are all the challenges with fixed output boilers facing a very wide, dynamic heat load throughout the season.
hot_rod
Re: What To Look For When Replacing a Natural Gas Boiler
One thing you can try is to drop by your local hvac supply company and ask them who buys a lot of modcons. This will at least get you the contact who does this type of work.
When looking at a new unit, make sure to check what size you actually need, simplest is fuel use calculation. Very few houses out there that need a 199k boiler.
Kaos