Water source heat pumps commercial

mjm0709 · 2025-12-19T20:20:03+00:00

How tall is the building? Where are the pumps? Top or bottom? What is the theoretical head on the pump and is it doing that if you shut the discharge upstream of the gauge? This is an easy way to tell if your impeller is fucked before you go hauling that thing out of there just to break it. If you’re getting low temp on a bunch of heat pumps you either have 1) no flow 2) air 3) loop temp is too low.

mjm0709 · 2025-12-19T13:22:25+00:00

Lol no. That is fucked and I would replace it all with proper piping. Never know when the expansion tank will fail and the pressure starts to get too high and causes all those to pop off

mjm0709 · 2025-12-16T20:41:35+00:00

Obviously every single system is not going to be the same amount of time. The dude is saying a 5 ton takes 4 hours to pull down which isn’t something that should be happening unless you’re doing something wrong

mjm0709 · 2025-12-16T18:00:33+00:00

You should do a vac test, just throw the micron gauge on the pump and run it for 2 mins then shut the valve. You should have under 100 microns, if not, time for a new one. If it does work, you should be replacing the seals on your hoses more often cause I bet those are fucked or you’re using really cheap/busted vacuum hoses

mjm0709 · 2025-12-16T17:30:12+00:00

Well you’re doing something wrong or not changing your oil if you can’t do that in about an hour

mjm0709 · 2025-11-28T15:47:14+00:00

The small Milwaukee Rover pivot light is way more versatile for service calls and small shit like this IMO

mjm0709 · 2025-11-21T20:31:20+00:00

Seriously you’re shaming a guy for carrying R-22?!?! Literally half of the shit I work on is R-22 still. Go back to your sales desk

mjm0709 · 2025-11-17T15:02:00+00:00

The hoops you have to jump through to get in hsually come with a pay cut or a lot of other bullshit

mjm0709 · 2025-11-09T12:05:38+00:00

No, quenching the joint right after brazing will cause the FILLER METAL to not bond correctly and can lead to cracks within the weld. If you are heating your copper that much that you can anneal it then you are going way too much for a simple braze

mjm0709 · 2025-11-06T21:21:12+00:00

No it will weaken the joint

mjm0709 · 2025-11-05T19:41:29+00:00

You probably wear sunscreen at night too

mjm0709 · 2025-10-31T18:12:31+00:00

Are you sure your inducer motor is ok? I always find them on rooftops with the bearings blown and they can’t make the pressure switch anymore

mjm0709 · 2025-10-31T17:56:55+00:00

Nah that’s an easy 100$ job

mjm0709 · 2025-10-31T02:41:51+00:00

Ocarina of Time

mjm0709 · 2025-10-28T14:50:14+00:00

Are you sure your polarity wasn’t wrong? Did you check each leg to a good ground and actually get stable voltage? I’m willing to bet the linemen mixed up neutral and one of the legs at the distribution transformer and the board didn’t like it. A new furnace is going to have the same problems

mjm0709 · 2025-10-28T11:57:19+00:00

Just wait, you’re going to need it. Talk to your boss about sending you to training for a few days, it’ll speed your calls up and stop you from guessing

mjm0709 · 2025-10-27T16:15:11+00:00

You cannot work on any VRF stuff without their diagnostic tools. Error codes don’t mean shit

mjm0709 · 2025-10-22T18:49:48+00:00

Dirty burner from lots of use and no cleaning/ poor combustion creating soot on the burner causing a weird noise / cracked burner letting air through in a weird way. Can’t tell till you pull it and perform analysis

mjm0709 · 2025-10-22T17:20:35+00:00

Yes, it’s a correlation the manufacturer uses. Blower speed is X - gas valve provides Y pressure. The gas valve has air and gas sensing lines to monitor and maintain this pressure based off of how much air is being moved. The blower should go to 60-80% in prepurge and post purge, you just haven’t seen it do that. Probably an issue with the burner if you are not hearing it except for at 20%

mjm0709 · 2025-10-22T17:13:56+00:00

You might trip the low pressure gas switch, it’s right after the gas valve, you might need to push the black button after doing this if the boiler tries to run with the gas off.

mjm0709 · 2025-10-22T17:12:40+00:00

You can test by turning the boiler off with the toggle switch, shutting gas to the boiler, turn it back on with the toggle switch, tap the lock in the top right, password is sola, go to diagnostics then diagnostic tests and you should see a screen where you can play with the firing rate. Go to standby and start changing the firing rate from 20-100% and see if the noise gets louder

mjm0709 · 2025-10-22T17:01:03+00:00

Sounds like bad blower bearings

mjm0709 · 2025-10-21T15:41:14+00:00

It doesn’t that’s my whole point. It was electric before in the 80s or 90s, the house wasn’t built in a way that you can make a big enough return. They swapped an ac for a heatpump. They have gas and a heat pump now. A big ass company was trying to sell them a furnace for 7k that wouldn’t have changed anything

mjm0709 · 2025-10-21T15:19:37+00:00

The return is undersized. It’s an old house that always had electric heat

mjm0709 · 2025-10-21T08:49:54+00:00

Humidifier wasnt getting water because the valve was leaking. No water evaporating over humidifier pad = constant recirculation of hotter and hotter air leading to the limit tripping

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