Hey Folks, We have had our new boiler (Heatmaster SS G200) hooked up and running since this past October 2018. The house heat and hot water was perfect for the first 3 months, now about 3 weeks ago, the DHW temp has dropped which also is resulting lower hot water pressure and my wife complaining a lot. (cold water pressure is fine). The house heat is fine and thermostat holding temp feeling warm. Could anyone offer any suggestions on what the issue could be with the DHW temp? Keeping in mind I am new to this. Here's some info below on setup. -Heatmaster SS G200 OWB (210,000 BTU/hr - 195 gallons) -Run is approx. 250' one way (approx 500' total) -outside lines are below 4' frost line, probably 5-6' - well insulated rated at -50C -using 1" pex in house, and off of circulating pumps which are located in the back of the boiler -the boiler mixing pump is Grundfos UPS15-58FC - 3 speeds (set to Medium per manual for G200 model) -the main circulating pump is Grundfos UPS26-99FC - 3 speeds (currently set to Medium) -HEX on water heater is AIC LA14-30X -there is mixing valve on water heater installed and still set to hottest setting - 160F - so no cold water should be mixing in at warmest setting I think, plus it's new -water-air exchanger in furnace I don't have spec. info on, house heat is fine though -fuel is mostly Oak with 15-20% mc -on Well for water and main well pump is set to 35/55 psi (was fine when hot water coming in was really hot) -boiler temps/timings are still at factory settings below: Set Temp: 180F Differential: 10F Low Temp Shut down: 140F Timer Settings: only happen after burn cycle to 180F, then timer settings reset too if water temp calls for heat based on Differential. On Delay: 90 minutes On Time: 3 minutes Off Time: 30 minutes Note: High Limit Switch - cuts power to fan if temp rises above 190F - I don't think this is adjustable. At first I thought the DHW temp drop was due to colder temps outside as we did have a cold snap, (-20C, feels like -30C, etc) but it's warmed up now (-8C feels like -16C) and the other day had a thaw of +4C - same issue with hot water - feels luke warm from shower/tub and washing maching with very little pressure. The sinks are a bit warmer, but nothing like it was before this issue started about the beginning of January 2019. Before, the hot water in shower was scalding on full hot, and we would have to turn down a bit with shower tap, which adds bit of cold water, which kept the pressure up, and water was still very warm and comfortable. Now we put shower tap to full hot, feels luke warm, weak pressure, wife complains. When the issue started, main circ. pump was on High for cold snap for about 2-3 weeks - I thought maybe I had too much flow (no idea if that is a possibility, just guessed), put back to Medium last night as that was what it was at for Oct, Nov, Dec, when everything worked great. Issue is the same for DHW at Medium, again house temps feel fine. The Boiler is reaching temp of 180F no problem it seems. Suggestions? Thanks for reading if you got this far. Unfortunately my dealer who installed sucks at getting back to me, probably sipping drinks in Mexico with all his boiler money. I wanted to give as much details in first go - I don't have a temp gun right now to take proper temp readings, but the lines feel hot everywhere, supply/return in house and out at boiler - no lines feel cool. I know that's not much help. Some initial questions I've been wondering about for my troubleshooting are: 1. what should my main circ. pump (Grundfos UPS26-99FC) be set to based on the above setup info? 2. not sure if this even matters, but the cold water intake valve hooked up to HEX, then into bottom of water heater, should that be open 100%, 50%, 25%? Thought here is that cold water is passing through HEX too quickly to get properly heated...or is that not an issue and it should be open 100% meaning that water would come in to HEX between 35 and 55 PSI? Any help appreciated.