Start-up – Mammoth 7 to 24 Tons: High Efficiency, Superior IAQ Twin and Quad Circuit Horizontal and Vertical (M-Vintage) User Manual
Page 10

10
MAMM-WSHP-IOM-1MA (November 2011)
1. Open all valves to full open position and turn on
power to the heat pump.
2. Set room temperature sensor for “Fan Only” opera-
tion by selecting “Off” at the system switch and 
“On” at the fan switch. If “Auto” fan operation is se-
lected, the fan will cycle with the compressor. 
Check for proper air delivery. 
3. M-Vintage horizontal and vertical units have time
delays which help protect the compressor(s) 
against short cycling. In the cooling mode, after a 
few minutes of operation, check the discharge 
grilles for cool air delivery. Measure the tempera-
ture difference between entering and leaving water. 
It should be approximately 1 ½ times greater than 
the heating mode temperature difference. 
4. In the heating mode, measure the temperature dif-
ference between entering and leaving air and en-
tering and leaving water. With entering water of 60°
F to 80°F, leaving water should be 6°F to 12°F 
cooler, and the air temperature rise through the M-
Vintage horizontal and vertical units should not ex-
ceed 35°F. If the leaving air temperature falls be-
low 35°F, adjust water flow to the unit to >3 gpm/
ton to avoid freeze damage to the unit. 
Start-up
5. Fill the p-trap with water to ensure that negative
pressure does not pull drain gases into the unit.
6. Check the elevation and cleanliness of the conden-
sate line. If the air is too dry for sufficient dehumidi-
fication, slowly pour enough water into the conden-
sate pan to ensure proper drainage. 
7. If the unit does not operate, check the following
points: 
a) Is supply voltage to the M-Vintage horizontal and 
vertical units compatible? 
b) If the M-Vintage horizontal and vertical units op-
erates but stops after a brief period: 
i) Is there proper airflow? Check for dirty filter, 
incorrect fan rotation or incorrect ductwork. 
ii) Is there proper water flow rate within tem-
perature limits? Check water balancing; back-
flush unit if dirt clogged. 
iii) See troubleshooting guide on page 16 for 
more tips. 
